Category: Medicine Forms

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1) A previously healthy 57-year-old woman is admitted to the hospital for evaluation of a 3-week history of increasing…

Nephrogenic diabetes insipidus

• Middle-aged woman with hyperparathyroidism complicated by severe hypercalcemia presents with significant polyuria and volume depletion, likely in the setting of calcium-induced nephrogenic diabetes insipidus (kidneys unresponsive to ADH –> Dilute urine)
• Key idea: Common causes of nephrogenic diabetes insipidus include hypercalcemia use and chronic lithium toxicity
• Key idea: Differential for production of high amounts of dilute urine
  • Nephrogenic diabetes insipidus: Hypernatremia, urine concentration increases by less than 50% after administration of ADH
  • Central diabetes insipidus: Hypernatremia, urine concentration increases by at least 50% after administration of ADH, often in patients with head trauma or mass
  • Psychogenic polydipsia: Hyponatremia, often in patients with psychosis

2) A 37-year-old man comes to the physician because of difficulty swallowing for 6 days. He says that…

HIV infection with candidal esophagitis

• Patient with IVDU and 25 lbs of unintentional weight loss over past year presents with dysphagia and thick white plaques in the mouth concerning for candidal esophagitis
• Key idea: The most common cause of esophagitis in HIV is candidal esophagitis, but if the patient has severe pain with swallowing (rather than difficulty swallowing) and lack of thrush then you should highly consider viral esophagitis, with the two most common culprits being HSV esophagitis (round/ovoid ulcers) and CMV esophagitis (deep linear ulcers)
• Key idea: If a patient has dysphagia to solids and liquids, consider a motility issue (achalasia, ALS, etc.), whereas if a patient has dysphagia to solids initially and then develops dysphagia to liquids then you should consider an obstructive pathology (cancer, stricture, etc.)

3. A 27-year-old nulligravid woman comes to the physician because of a 4-month history of irregular menses…

CT scan of the abdomen

• Young woman presents with irregular menses, hirsutism and a significantly elevated DHEA sulfate level with a positive overnight dexamethasone suppression test concerning for Cushing syndrome due to increased androgen production from adrenals, which should be worked up with abdominal CT scan
• Key idea: Dehydroepiandrosterone (DHEA) is produced by both the ovaries and adrenals, but DHEA Sulfate is ONLY PRODUCED BY THE ADRENALS and high levels of DHEA sulfate should make you concerned about adrenal hyperplasia or carcinoma
• Key idea: Hirsutism is defined by hair in male-patterned areas (upper lip, chest, etc.) and can be seen in setting of mild androgen elevations (e.g., PCOS), but if a patient has signs of virilization (male pattern baldness, cliteromegaly, deep voice, increased muscle mass) then you must investigate for causes of significantly elevated androgen levels (ovarian mass, adrenal mass, exogenous steroids, etc.) and can’t just blame PCOS

4) An 87-year-old woman comes to the physician because of a 2-week history of constant, increasing abdominal pain…

Pancreatic adenocarcinoma

• Elderly woman with a history of cholecystectomy who presents with subacute abdominal pain and pruritis and is found to have cholestatic LFT elevation with dilated CBD and pancreatic duct most concerning for pancreatic adenocarcinoma
• Key idea: Most common cause of cholestatic LFT elevation with a dilated common bile duct would be gallstones, but that is highly unlikely in a patient whose had their gallbladder removed so must think about a mass lesion obstructing the CBD
• Key idea: When a patient has LFT abnormalities, first branch point is whether the pattern is hepatocellular (ALT/AST elevation >> Alk phos and bilirubin, due to primary injury to liver in setting of viral hepatitis, toxins (acetaminophen), shock liver, etc.) or cholestatic (Alk phos and direct hyperbilirubinemia >> ALT/AST elevation, due to impaired excretion of bile in setting of gallstones, pancreatic cancer, cholangiocarcinoma, etc.)
• Key idea: Best imaging test for pancreatic cancer of the head of the pancreas (which often presents with cholestatic LFT elevation) is ultrasound, whereas the best imaging test for pancreatic cancer of the body of the pancreas (which often presents with diabetes mellitus) is a CT of the abdomen

5) A 37-year-old woman comes to the physician because of a 3-week history of a rash over her left wrist…

Exposure to nickel

• Young woman began wearing a new watch and then noted a rash in the area of exposure, most consistent with contact dermatitis
• Common triggers of contact dermatitis include nickel, poison oak, new soap/detergent, hair dyes, and topical antibiotics and importantly the rash will be distributed along the area of exposure

6) A 47-year-old man is admitted to the hospital for treatment of alcoholic pancreatitis. He is currently…

Penicillin

• A middle-aged man with high-risk sexual contacts is found to have painful vesicular lesions on the penile shaft and a painless shallow ulcer on the glans penis, most consistent with HSV infection of the penile shaft and syphilis infection of the glans penis
• Key idea: HSV infection treated with acyclovir/valacyclovir, whereas syphilis treated with penicillin G
• Key idea: RPR has low sensitivity for primary syphilis infection (painless chancre)
• Painful genital lesion:
  • HSV: Multiple vesicles or shallow ulcers
  • Chancroid (Haemophilus ducreyi infection): Single necrotizing/purulent ulcer
• Painless genital lesion:
  • Syphilis: Shallow ulcer (chancre) with painless lymphadenopathy
  • Lymphogranuloma venereum (chylamydia): Painless genital lesions with painful lymphadenopathy
  • Condyloma acuminata (HPV): Fleshy, crusty, pink, wart-like

7) A 47-year-old woman comes to the physician because of a 3-year history of progressive swelling of her left…

Valvular insufficiency of deep veins

• Middle-aged woman with history of DVT of her left leg who presents with chronic history of left calf swelling with prominent varicose veins and overlying hyperpigmentation with a reassuring DVT ultrasound most consistent with venous stasis c/b venous stasis dermatitis due to venous insufficiency
• Key idea: Common precipitants of venous stasis include cellulitis/infection, DVT, and chronic edema (CHF, cirrhosis, etc.) because they stretch/damage the valves within veins, leading to chronic edema
• Key idea: Common for patients with chronic venous stasis to develop overlying erythematous rash and can even develop venous ulcer over the medial shin

8) A 37-year-old man is brought to the emergency department 2 hours after he was involved in a motor vehicle collision…

Pulmonary contusion

• Young man involved in a motor vehicle collision presents with severe pleuritic chest pain and is found to have bruises over the chest with bilateral interstitial infiltrates on chest x-ray, concerning for pulmonary contusion
• Key idea: Pulmonary contusion classically presents with tachypnea, tachycardia and/or hypoxia with rales or decreased breath sounds <24 hours after blunt thoracic trauma
• Key idea: Imaging classically demonstrates patchy infiltrates that underlie bruising and are not restricted by anatomical border
• Key idea: ARDS can also develop after trauma, but infiltrates are typically bilateral and do not manifest for 24-48 hours
• Fat embolism –> Classically presents 24-72 hours after long bone fracture with respiratory distress, neurologic dysfunction and petechial rash
• Flail chest –> Traumatic fracture of several contiguous ribs leads to isolated chest wall segment with paradoxical movement of chest wall segment (moves inward during inspiration and outward during expiration)

9) An 82-year-old man with metastatic lung cancer is brought to the emergency department by his children because…

Follow the advance directive

Key idea: The whole point of an advanced directive is to guide a patient’s care in the case that they become unable to voice their own opinion, and therefore the rules/guidelines for care set forth in the advanced directive supersedes the desires of loved ones

10. A 47-year-old woman comes to the physician for a health maintenance examination. She has mild hyperparathyroidism…

Obesity

• Key idea: The #1 risk factor osteoarthritis is obesity given that increased weight –> increased chronic wear-and-tear on joints
• Key idea: Lack of exercise would be a risk factor for osteoporosis given bones are strengthened in the setting of load-bearing exercise (obesity is actually protective against osteoporosis!)

11) A 52-year-old woman is brought to the emergency department by her husband because she says that…

Ruptured congenital aneurysm

• Middle-aged woman presents with “worst headache” of her life with severe hypertension, nuchal rigidity and extremely high RBC count in the CSF most concerning for a subarachnoid hemorrhage
• Key idea: Meningeal signs (neck stiffness) and fever can be seen in both meningitis and subarachnoid hemorrhage, with the CSF findings being the main differentiator in this case
• Epidural hematoma –> Individual hits their head with loss of consciousness, followed by brief lucid period and then acute worsening of neurologic status
• Subdural hematoma –> 1) Elderly patient who falls down and then presents with subacute/chronic altered mental status with asymmetric neurological signs OR 2) Shaken baby syndrome (retinal hemorrhages, etc.)

12) A previously healthy 27-year-old woman comes to the physician because of a 3-month history of low-grade fever…

Crohn disease

• Young woman presents with chronic fatigue, intermittently bloody diarrhea and 10-lb weight loss concerning for inflammatory bowel disease (IBD) such as Crohn disease or Ulcerative colitis
• Key idea: In young person presenting with chronic GI symptoms, typically you are distinguishing between IBS and IBD, with inflammatory signs (fevers, bloody diarrhea, weight loss, elevated CRP/ESR) being more consistent with IBD
• Celiac disease –> Fat malabsorption, dermatitis herpetiformis (vesicular rash on extensor surfaces), and iron deficiency anemia (due to disease affecting duodenum)

13) A previously healthy 22-year-old woman comes to the physician because of a 2-day history of frequent pain with urination…

Nitrofurantoin therapy

• Young woman presenting with acute dysuria and suprapubic tenderness, most consistent with a simple UTI –> Treatment options include nitrofurantoin, TMP-SMX and fosfomycin
• Oxybutynin –> Anticholinergic medication used as first-line treatment in urge incontinence
• Midurethral sling procedure –> Used in setting of pelvic prolapse, which can lead to stress incontinence

14) A 62-year-old man comes to the physician because of a 2-week history of severe left ear pain. At the onset…

Necrotizing otitis externa

• Middle-aged man with chronic history of poorly controlled diabetes who presents with severe ear pain with an edematous left ear canal with granulation tissue who is found to have a neutrophilic leukocytosis and elevated ESR, concerning for necrotizing otitis externa
• Key idea: Risk factors for necrotizing otitis externa include advanced age (>60), diabetes mellitus (relative immunosuppression) and aural irrigation
• Key idea: Presence of granulation tissue in ear canal pathognomonic for necrotizing otitis externa and in severe cases can lead to cranial nerve deficits (CN7, CN10, etc.)
• Key idea: Both simple and necrotizing otitis externa most often caused by Pseudomonas infection, with necrotizing otitis externa being treated with IV antipseudomonal antibiotics +/- surgical debridement

15) A 27-year-old woman is brought to the emergency department because of a 6-hour history of shortness…

Hot tub use

• Young woman who recently moved to a new apartment building with a hot tub and since moving has begun to develop intermittent episodes of self-resolving dyspnea and cough with diffuse fine crackles on physical exam concerning for hypersensitivity pneumonitis c/b interstitial lung disease
• Key idea: Common triggers for hypersensitivity pneumonitis include birds, hot tubs, and hay (“farmer’s lung”)
• Key idea: Many times hypersensitivity pneumonitis is mistakenly diagnosed as recurrent bouts of pneumonia because it leads to respiratory symptoms with infiltrates on CXR, but episodes should self-resolve without treatment as long as exposure is withdrawn
• Key idea: On the NBME exam, crackles in the lungs are either fluid (CHF, etc.) or interstitial lung diseases (IPF, etc.)

16) A 42-year-old man is brought to the emergency department 30 minutes after the onset of severe chest pressure and nausea…

Complete heart block

• Young man with significant cardiac risk factors (60 pack-years, sedentary lifestyle) presents with chest pressure and nausea and is found to be severely bradycardic with an EKG showing ST segment elevations in leads II, III and aVF most concerning for inferior MI complicated by complete heart block
• Key idea: Complications associated specifically with inferior MI include:
  • Heart block: Right coronary artery supplies the AV and SA nodes, so they can become dysfunctional in setting of bradycardia
  • Right-sided MI: Right coronary artery supplies the right ventricle, with loss of right ventricle making patients very preload sensitive –> Often presents with abrupt drop in BP in response to vasodilators (nitrates, etc.)
  • Papillary muscle rupture: Posteromedial papillary muscles supplied by right coronary artery, so can become ischemic and lead to flash mitral regurgitation with acute CHF about 3-5 days post-MI
• First degree AV block –> Prolonged PR interval (>200 ms) but no dropped QRS’s
• Mobitz type 1 block –> PR interval gradually prolongs until a QRS is dropped, and then the cycle restarts (regularly irregular)
• Mobitz type 2 block –> QRS complexes randomly dropped

17) A 67-year-old man with type 2 diabetes mellitus is admitted to the hospital because of a 1-day history of…

0.9% saline

• Elderly patient with baseline diabetes and creatinine of 1.4 mg/dL needs to have a CT scan performed, and therefore should receive fluid bolus prior to scan to reduce risk of contrast-induced nephropathy
• Key idea: Potential triggers of acute tubular necrosis include:
  • Severe ischemia
  • Heavy metals
  • Contrast
  • Ethylene glycol
  • Myoglobin (rhabdomyolysis)
  • Aminoglycosides (gentamicin)
  • Urate (tumor lysis syndrome)

18) A 52-year-old woman comes to the physician for a routine health maintenance examination. She feels well…

Add simvastatin to her current regimen

• Middle-aged patient with diabetes and hypertension who despite good control of her HgbA1c and LDL should be placed on a statin
• Indications for statin:
  • History of atherosclerotic cardiovascular disease (stroke, peripheral vascular disease, MI)
  • LDL > 190
  • Diabetic aged 40-75 yo
  • 10-year pooled ASCVD risk > 7.5%
• Key idea: HgbA1c goal is often less than 7.0%, with higher cutoffs being used in older patients given potential risks associated with hypoglycemia in that population (falls, etc.)

19) A 27-year-old woman comes to the physician because of a 3-month history of fatigue, heat intolerance, generalized…

Toxic adenoma of the thyroid gland

• Young woman presents with chronic heat intolerance, anxiety, palpitations and weight loss and is found to have a low TSH and discrete nodule on her thyroid gland most consistent with a toxic adenoma
• Key idea: Cold thyroid nodules (elevated-normal TSH) are more concerning for malignancy compared to a hot nodule (low TSH, hyperthyroid symptoms), making carcinoma less likely in this case
• Graves disease –> Hyperthyroidism with diffuse thyroid enlargement (due to diffuse overstimulation by thyroid-stimulating antibodies)
• Toxic multinodular goiter –> Hyperthyroidism with multiple thyroid nodules

20) A 57-year-old man comes to the physician because of a 3-day history of a painful rash on his right index finger…

Oral acyclovir

• Middle-aged dentist presents with painful vesicular rash of his right finger with ipsilateral axillary lymphadenopathy most concerning for herpetic whitlow –> Treat with oral valacyclovir/acyclovir
• Key idea: Herpetic whitlow classically affects dentists because they are sticking their hands around patient’s mouths, which may have HSV cold sores
• Key idea: For the NBME exam, vesicular eruptions should primarily make you think of viral infections, eczematous dermatitis (atopic dermatitis, contact dermatitis) and dermatitis herpetiformis (celiac disease)

21) A 27-year-old woman with systemic sclerosis (scleroderma) comes to the physician because of a 4-month history…

Cor pulmonale

• A young woman with scleroderma presents with chronic progressive shortness of breathe and is found to have decreased lung expansion and diffuse inspiratory crackles (concerning for interstitial lung disease) with associated neck vein distention, lower extremity edema and a parasternal heave concerning for pulmonary hypertension (Cor pulmonale)
• Key idea: Cor pulmonale = Pulmonary hypertension in setting of obstructive/restrictive lung disease because these disease lead to diffuse lung hypoxia –> diffuse vasoconstriction within lung –> increased afterload/resistance faced by right ventricle
• Key idea: Features that should be concerning for pulmonary hypertension include parasternal heave (RV faces increased afterload –> RV hypertrophy –> Stronger “heartbeat” since the RV is the most anterior heart structure), loud S2 (due to increased afterload faced by RV) and features of right-sided HF (JVD, LEE, hepatomegaly) WITHOUT left-sided heart failure symptoms (pulmonary edema)
• Key idea: Causes of pulmonary hypertension include:
  • Genetic mutation (pulmonary arterial hypertension) –> Progressive dyspnea with pulmonary hypertension symptoms in young woman
  • Left-sided HF
  • Obstructive/Restrictive lung disease (Cor pulmonale)
  • Chronic thromboembolic disease
  • Other (HIV, sarcoidosis, schistosomiasis, etc.)
• Key idea: Lung crackles consistent with fluid (CHF) and interstitial lung disease

22) Twenty-four hours after nearly drowning, a 24-year-old man in the intensive care unit has not regained…

Acute respiratory distress syndrome

• A young man who nearly drowned one day ago develops progressive hypoxia with a current PO2 of 60 on 100% FiO2 and diffuse bilateral infiltrates on CXR, concerning for acute respiratory distress syndrome in setting of “secondary drowning”
• Key idea: Aspirated liquid during near-drowning event can wash away surfactant, leading to insidious development of acute respiratory distress syndrome within the next 72 hours
• Key idea: ARDS defined by PaO2/FiO2 ratio < 300, with this patient having a ratio of 60 (60/1)
  • Normal PaO2/FiO2 ratio is ~500 (100/0.21 given that normally 21% of air we are breathing is oxygen)

23) A 57-year-old woman comes to the physician because of fatigue over the past 6 months. She has had…

Serum antimitochondrial antibody assays

• Middle-aged woman with strong family history of autoimmune disease presents with chronic weight loss, pruritis and xanthelasmas and is found to have hepatomegaly with a cholestatic pattern of LFT elevations without evidence of biliary obstruction on abdominal ultrasound, concerning for primary biliary cirrhosis (diagnosed via positive antimitochondrial antibodies)
• Primary sclerosing cholangitis –> Associated with ulcerative cholitis, positive p-ANCA, leads to alternating strictures of the common bile duct (“beads on a string”)
• Key idea: When a patient has LFT abnormalities, first branch point is whether the pattern is hepatocellular (ALT/AST elevation >> Alk phos and bilirubin, due to primary injury to liver in setting of viral hepatitis, toxins (acetaminophen), shock liver, etc.) or cholestatic (Alk phos and direct hyperbilirubinemia >> ALT/AST elevation, due to impaired excretion of bile in setting of gallstones, pancreatic cancer, cholangiocarcinoma, primary sclerosing cholangitis, primary biliary cirrhosis, etc.)
• Key idea: Patients with impaired biliary excretion commonly develop generalized pruritis due to deposition of bile salts in the skin
• Acute hepatitis B infection –> Hepatocellular liver injury (AST/ALT >> Alk phos and direct bilirubin)
• HIDA scan –> Useful if biliary disease is suspected but ultrasound is ambiguous

24) A previously healthy 72-year-old man is brought to the emergency department because of episodic memory loss…

Phlebotomy

• Elderly patient presents with chronic history of pruritis in his legs presents with acute pain in his toe and acute neurologic symptoms (dizziness, double vision) with labs most notable for erythrocytosis, leukocytosis and borderline thrombocytosis most concerning for polycythemia vera –> Treatment with phlebotomy acutely followed by chronic hydroxyurea and/or ruxolitinib (JAK kinase inhibitor)
• Key idea: Unique symptoms/features associated with polycythemia vera include:
  • Transient neurologic symptoms (due to thrombosis in setting of hyperviscosity)
  • Aquagenic pruritis (itching after a warm bath/shower due to mast cell degranulation)
  • Erythromelalgia (burning cyanosis of the hands/feet)
• Key idea: Two diseases in which phlebotomy is a useful treatment are polycythemia vera and hemochromatosis

25) A 77-year-old man with alcoholism is brought to the emergency department after his landlord found him unconscious…

Heat stroke

• Elderly man found unconscious and hyperthermic in his apartment on a hot summer day found to have normal exam other than warm, dry skin and labs most notable for hypernatremia, acute kidney injury and elevated CK with urinalysis showing positive blood dipstick but few RBCs most consistent with heat stroke complicated by rhabdomyolysis in setting of being down/unconscious for extended period of time
• Key idea: Hypernatremia due to insufficient fluid intake (such as patient lacking access to fluids) or excessive fluid losses (insensible losses in sweat, diabetes insipidus)
• Heat stroke: Elevated temperature and CUS dysfunction due to impaired thermoregulation (warm/dry skin indicates insufficient sweating)
• Heat exhaustion: Elevated temperature WITHOUT CNS dysfunction due to inadequate salt and water replacement
• Delirium tremens –> Patient presenting with confusion and sympathetic hyperactivity (hypertension, tachycardia, sweating) 2-4 days after last alcoholic drink
• Neuroleptic malignant syndrome –> Patient exposed to antidopaminergic medication (antipsychotic, metoclopramide) who presents with Malignant FEVER –> Myoglobinuria, Fever, Encephalopathy, Vitals unstable, Elevated enzymes (CK) and Rigidity
• Wernicke encephalopathy –> Patient who is nutritionally deficient (alcoholic, eating disorder) presenting with triad of confusion, ataxia and ophthalmoplegia

26) A 62-year-old woman comes to the physician for a follow-up examination. She has chronic renal failure secondary…

Decreased absorption due to decreased serum 1,25-dihydroxycholecalciferol concentration

• Key idea: Patients with chronic kidney disease develop hypocalcemia because (1) they have decreased activation of 25-vitamin D to 1,25-vitamin D (which occurs in the kidney) and (2) they have increased phosphate levels, which bind calcium and lead to decreased free calcium
• Key idea: Patients with CKD typically have low calcium levels, high phosphate levels and high parathyroid hormone levels (due to decreased calcium levels)
• Key idea: If you ever see a patient with kidney disease (AKI) and HYPERcalcemia, you should consider multiple myeloma because it leads to hypercalcemia and damage to the kidney (due to clogging of kidney tubules)

27) A 42-year-old woman comes to the office because of a 3-month history of progressive shortness of breath…

Tracheomalacia

• A middle-aged woman who was recently intubated and ventilated presents with several months of dyspnea, cough and intermittent high-pitched, end-expiratory wheezes most concerning for tracheomalacia (softening of trachea leading to end-expiratory collapse)
• Key idea: Intubation longer than 7-10 days can often lead to damage to the trachea and surrounding structures
• Key idea: Tracheomalacia leads to expiratory stridor, whereas laryngomalacia leads to inspiratory stridor
• Hypersensitivity pneumonitis –> Intermittent episodes of shortness of breathe after exposure to bird droppings, hot tubs, hay, etc.
• Asthma –> Episodic shortness of breathe and/or cough that is triggered by cold air, exercise and the nighttime

28) A 38-year-old African American man with accelerated hypertension is admitted to the hospital. His blood pressure is…

Uremia

• Young man with hypertensive emergency (BP > 180/120 with end-organ changes) develops significant kidney dysfunction complicated by substernal chest pain with a pericardial friction rub, most consistent with uremic pericarditis
• Common causes of pericarditis:
  • Post-viral
  • Uremia
  • Lupus erythematosus
  • Inflammatory pericarditis days after inflammation of heart (MI or CABG procedure)
  • ~6 weeks after inflammation of heart (MI or CABG procedure) due to Dressler’s syndrome
• Key idea: Indications for dialysis can be remembered through AEIOU, with the U standing for Uremia –> specific indications for dialysis include uremic pericarditis, bleeding or encephalopathy

29) An unconscious 37-year-old woman is brought to the emergency department after being found in an abandoned house…

Increased creatine kinase activity

• Young woman is found down likely in setting of alcohol intoxication and is found to have renal dysfunction (creatinine of 3.0) with pigmented casts, most concerning for rhabdomyolysis
• Lab findings in setting of rhabdomyolysis include hyperkalemia, metabolic acidosis, hyperphosphatemia and increased creatine kinase due to damage to myocytes
• Common causes of rhabdomyolysis:
  • Intense muscle activity (exercise, seizures, etc.)
  • Prolonged immobilization or crush injury
  • Drug/medication (statins, cocaine, alcohol, etc.)
• Key idea: Rhabdomyolysis classically leads to positive blood on urine dipstick but no/minimal RBCs on urine microscopy given that the urine dipstick picks up blood, hemoglobin and myoglobin

30) During transfusion of a second unit of crossmatched packed red blood cells for lower gastrointestinal bleeding…

Acetaminophen

• Elderly woman develops fever and chills while receiving transfusion with a negative Coombs test, most consistent with acute febrile non-hemolytic reaction that is best treated with antipyretics such as acetaminophen
• Hemolytic transfusion reaction –> Dark urine, flank pain and positive Coombs test
• Epinephrine –> Patient receiving blood transfusion who immediately develop urticaria, hypotension, GI symptoms and bronchoconstriction (anaphylactic transfusion reaction)
• Dantrolene –> Useful for neuroleptic malignant syndrome and malignant hyperthermia

31) A 37-year-old woman comes to the physician for a routine follow-up examination. She has mild, intermittent…

Add fluticasone

• Young woman with known history of asthma currently controlled with as-needed albuterol presents with increase frequency of episodes of dyspnea and wheezing (3-4 times per week), therefore meeting criteria for mild persistent asthma and likely benefitting from addition of a daily inhaled steroid (such as fluticasone)
• Key idea: Asthma severity graded based upon symptoms frequency and frequency of nighttime awakenings:
  • Intermittent asthma: 2 or fewer days of symptoms per week and 2 or fewer nighttime awakenings per month –> Short-acting beta agonist as needed
  • Mild persistent asthma: 3 -6 days symptoms per week and 3-4 nighttime awakenings per month –> Low-dose inhaled corticosteroid with short-acting beta agonist as needed
  • Moderate persistent asthma: daily symptoms and at least 1-3 nighttime awakenings per week –> Low-dose inhaled corticosteroid + Long-acting beta agonist (salmeterol)
  • Severe persistent asthma: symptoms throughout the day and 4+ nighttime awakenings per week –> High-dose inhaled corticosteroid + Long-acting beta agonist (salmeterol) +/- omalizumab (anti-IgE antibody) or oral corticosteroid
• Tiotropium 1st-line treatment for COPD

32) An otherwise healthy 41-year-old woman comes to the physician because of a lesion on the calf…

Surgical excision

• Young woman presents with an asymmetric, multicolored lesion on her left calf with irregular/unclear borders, concerning for a possible melanoma –> Next best step is surgical excision
• Key idea: Remember the ABCDE of pigmented lesions, with increased concern for pigmented lesions that are Asymmetric, have irregular Borders, have multiple Colors, have a Diameter of at least 6 mm, and that are Evolving
• Key idea: For pigmented lesions, can also use the “ugly duckling sign” to identify concerning pigmented lesions that look different than the patient’s other pigmented lesions or moles

33) A 62-year-old man comes to the physician because of a 2-month history of increasing fatigue, weakness…

Small cell carcinoma of the lung

• Elderly man with significant smoking history presents with chronic fatigue, weakness, hyperpigmentation, and weight loss and is found to have proximal muscle weakness with hypokalemia and hyperglycemia, concerning for small cell carcinoma complicated by Cushing syndrome due to paraneoplastic ACTH production
• Key idea: While classic Cushing syndrome due to an adrenal adenoma or pituitary tumor producing ACTH classically leads to weight gain, paraneoplastic Cushing syndrome classically leads to weight loss with particular thinning of extremities
• Hyperpigmentation due to fact that ACTH produced from a precursor molecule called POMC, with increased POMC leading to increased melanocyte stimulating hormone
• Hypokalemia due to excess cortisol stimulating mineralocorticoid (aldosterone) receptors, leading to hypokalemia and metabolic alkalosis
• Proximal muscle weakness concerning for myopathy, with differential including:
  • Steroid myopathy (Cushing’s or exogenous steroids)
  • Hypothyroid myopathy
  • Myositis (inflammation + proximal muscle weakness)
  • Statin-induced myopathy
• Hemochromatosis –> Hyperpigmentation, diabetes, arthritis (chondrocalcinosis), cirrhosis, cardiomyopathy
• Adrenal insufficiency –> Hypoglycemia, hyponatremia, hypotension, GI symptoms +/- hyperpigmentation and hyperkalemia (if primary adrenal insufficiency)

34) A 27-year-old woman comes to the physician because of a 1-year history of fatigue. She first noticed her fatigue…

Beta-Thalassemia trait

• Young woman presents with chronic fatigue and is found to have microcytic anemia with hemoglobin electrophoresis consistent with elevated hemoglobin A2 and hemoglobin F, concerning for beta-thalassemia trait
• Key idea: Hemoglobin electrophoresis detects RELATIVE levels of the different hemoglobin subtypes, and in the setting of beta-thalassemia will detect decreased relative abundance of Hgb A with increased levels of Hgb A2 and Hgb F given the fact that Hemoglobin A composed of 2 alpha and 2 beta subunits
• Key idea: Alpha thalassemia will have NORMAL hemoglobin electrophoresis findings because all the types of hemoglobin contain alpha subunits so production of all the hemoglobin subtypes will be decreased across the board –> best diagnostic study for alpha thalassemia is genetic testing
• Ways to differentiate between iron deficiency anemia and thalassemia:
  • IDA: Decreased iron and ferritin, increased red cell distribution width, decreased RBC count
  • Thalassemia: Normal iron studies, decreased red cell distribution width, increased RBC count (producing increased amounts of abnormal RBCs)

35) A 32-year-old homeless man is admitted to the hospital and placed in respiratory isolation because of a 2-week…

Tuberculosis

• Young homeless man with history of IVDU presents with subacute fever, chills, hemoptysis and weight loss and is found to have cavitary lung lesions in upper lung fields, most concerning for active tuberculosis
• Key idea: Most patients with tuberculosis have latent tuberculosis (asymptomatic disease), with tuberculosis commonly being reactivated in setting of immunosuppression (increased age, HIV, etc.) –> Therefore, in this patient with a history of IVDU who presents with active pulmonary tuberculosis, I would be concerned for HIV infection, which would lead to a false negative PPD given that the PPD skin test relies upon T cells within the skin (Type 4 hypersensitivity reaction)
• Aspiration pneumonitis would not present with a subacute/chronic course and classically leads to disease affecting the right lower lung fields
• Sarcoidosis –> Dyspnea, cough, hypercalcemia and bilateral hilar lymphadenopathy in a young African American woman

36) A 55-year-old man comes to the physician because of shortness of breath on exertion over the past 2 weeks…

Adequate control of blood pressure

• Middle-aged man lost from medical care with 30-pack year smoking history presents with 2 weeks of exertional shortness of breathe and is found to have hypertension, lung crackles, an S4 gallop, cardiomegaly with Kerley B lines and an echocardiogram showing LVEF of 40% most concerning for diastolic heart failure due to long-standing hypertension
• Key idea: S3 is a sign of volume overload (decompensated heart failure) whereas an S4 is often a sign of diastolic dysfunction (long-standing hypertension, aortic stenosis, HOCM, etc.)
• Key idea: Lung crackles should make you concerned about pulmonary edema (CHF, etc.) or interstitial lung disease (idiopathic pulmonary fibrosis, etc.)

37) A 67-year-old man comes to the emergency department because of a 3-month history of a mass in his right groin…

Immediate groin exploration

• Elderly man with intermittent, chronic groin mass presents with 3-hour history of persistent, painful, non-reducible groin mass most concerning for an incarcerated or strangulated hernia that requires immediate surgical intervention
• Key idea: An incarcerated hernia that has its blood supply cut off can become strangulated, with a high risk for perforation and/or necrosis
• Incision and drainage –> Treatment for abscess (fluctuant mass)
• Fine-needle aspiration biopsy –> Diagnostic study for thyroid mass

38) A 57-year-old homeless man is admitted to the hospital because of a 5-day history of moderate neck pain and…

Hematogenous dissemination of distant infection

• Middle-aged man with HIV and current IVDU presents with acute fever and neck pain and is found to have point tenderness over the cervical vertebral bodies with cervical imaging demonstrating collapse and destructive changes of C5 and C6, concerning for osteomyelitis
• Key idea: Point tenderness over the vertebral bodies (NOT the paraspinal muscles) is a concerning finding and should make you consider:
  • Fracture (osteoporosis, trauma, long-term steroid use)
  • Osteomyelitis (IVDU, fever, immunosuppressed)
  • Metastatic disease (weight loss, hypercalcemia, history of breast/lung/prostate CA)
• Reactivation of latent organism –> Tuberculosis classically leads to osteomyelitis of the vertebral bodies (Pott’s disease), but we would expect patient to have abnormal chest x-ray with cavitary disease of upper lung lobes

39) A 42-year-old woman comes to the physician 2 hours after the onset of headache and light-headedness. Her symptoms…

Not eating the mahimahi

• Young woman eating at a restaurant presents with flushed skin, headache and light-headedness, concerning for scombroid poisoning from mahimahi
• Key idea: Scombroid poisoning is a foodborne illness from eating spoiled fish high in histamine levels that leads to symptoms from vasodilation, including flushing, itching, headache and hypotension
• Key idea: Cooking, smoking or freezing the spoiled fish does NOT eliminate the histamine

40) A 42-year-old African American woman comes to the physician because of a 4-week history of cough…

Glucocorticoid therapy

• Young African-American woman presents with subacute cough and fatigue and is found to have hypercalcemia with decreased PTH levels with an x-ray demonstrating bilateral lung nodules, most concerning for sarcoidosis that should be treated with glucocorticoids
• Key idea: Sarcoidosis –> Non-caseating granulomas –> Increased 1-alpha hydroxylase activity in granulomas –> Increased Vitamin D activation –> Increased calcium levels
• Key idea: Hyperparathyroidism leads to increased calcium and decreased phosphate because the main goal of parathyroid hormone is to increase calcium (and decreasing phosphate will indirectly lead to increased calcium due to reduced calcium-phosphate binding), whereas hypervitaminosis D leads to increased calcium and phosphate because the main goal is increased bone mineralization and mineralization requires deposition of calcium-phosphate complexes

41) A 62-year-old woman comes to the physician because she is concerned about her risk for osteoporosis…

Alendronate

• An elderly woman with a history of DVT is found to have DEXA scan findings consistent with osteoporosis, and therefore should receive first-line treatment with a bisphosphonate (alendronate, zoledronic acid, etc.)
• Key idea: Patient’s history of DVT is a contraindication for treatment with estrogen and raloxifene given that both stimulate estrogen activity and therefore lead to a hypercoagulable state
• Key idea: Main risk factors for osteoporosis include increased age, decreased androgens (post-menopausal), decreased weight and corticosteroids (exogenous, Cushing’s syndrome)

42) A 77-year-old man with dementia, Alzheimer type, is brought to the physician because of a 1-week history of…

Catheterization of the bladder

• Elderly man with Alzheimer’s presents with subacute urinary incontinence is found to have tender suprapubic fullness with a weak urinary stream, most concerning for urinary retention that should be relieved with bladder catheterization both to improve patient’s symptoms and prevent post-renal acute kidney injury
• Key idea: Urinary retention can lead to overflow incontinence, with common causes of urinary retention including:
  • Benign prostatic hyperplasia (elderly men)
  • Atonic bladder (neurologic condition, post-delivery)
  • Uterine prolapse (elderly multiparous women)

43) A 57-year-old man comes to the physician for a routine examination. He feels well. He has rheumatoid…

Renal tubular acidosis

• Middle-aged man with history of rheumatoid arthritis and diabetes presents with significant metabolic acidosis (HCO3 of 10) with an AG of 12 and alkalotic urine, concerning for a renal tubular acidosis
• Anion gap = [Na+] – [HCO3-] – [Cl-], with a level >12 being consistent with AG metabolic acidosis
• Differential for non-AG metabolic acidosis(HARDASS)
  • Hyperalimentation (specifically total parenteral nutrition since amino acids given with chloride)
  • Adrenal insufficiency (loss of aldosterone –> retention of K+ and H+)
  • Renal tubular acidosis (either impaired HCO3 reabsorption or impaired H+ secretion)
  • Diarrhea (loss of K+ and HCO3-)
  • Acetazolamide (blocks bicarbonate reabsorption in proximal tubule; reason it is useful for elevation sickness where individuals are hyperventilating and develop respiratory alkalosis)
  • Saline infusion (increased volume –> decreased RAAS –> decreased aldosterone –> retention of K+ and H+)
  • Spironolactone (blocks aldosterone –> retention of K+ and H+)
• Note: I wouldn’t worry too much about different subtypes of RTAs, but rather just understand they lead to Non-AG metabolic acidosis due to impaired H+ secretion or impaired HCO3- reabsorption

44) A 67-year-old man comes to the physician for a routine health maintenance examination. He has no history of…

Antihypertensive therapy

• Key idea: #1 risk factor for stroke is hypertension, with adequate BP control being particularly important in this patient with severely elevated BP and signs of longstanding poorly controlled BP (S4)
• Key idea: #1 risk factor for atherosclerotic disease (MI, peripheral vascular disease) is smoking followed by diabetes

45) A 25-year-old man comes to the physician 1 day after noticing pink-tinged urine. Two days ago, he had an upper respiratory…

IgA nephropathy

• Young man with URI several days ago presents with 1-day of hematuria confirmed by urinalysis with a normal serum complement concentration, most consistent with IgA nephropathy
• IgA vasculitis –> Occurs during or days after infection, follows a viral URI (cough, conjunctivitis, etc.), normal complement level
• Post-strep glomerulonephritis –> Occurs 2-4 weeks after infection, follows strep throat (exudative pharyngitis + lymphadenopathy in a child), decreased complement level (Type 3 hypersensitivity reaction)
• Urethritis –> Sterile pyuria (WBCs in the urine but negative urine cultures)

46) A 47-year-old woman with hypertension comes to the physician for a follow-up examination. One month ago, her blood pressure was…

MR angiography of the renal arteries

• Middle-aged woman recently started on an ACE inhibitor for severe hypertension presents with persistent hypertension and a significant increase in her creatinine, concerning for possible renovascular disease that should be worked up with renal artery imaging
• Key idea: Patients with renovascular disease are often highly dependent upon angiotensin 2 mediated vasoconstriction of the efferent arteriole for sufficient glomerular pressure/filtration, and therefore classically will have a significant increase in their creatinine after initiating an ACE inhibitor or ARB that blocks efferent arteriole vasoconstriction
• 2 major causes of renal artery stenosis: Atherosclerosis (older patient, ASCVD risk factors), Fibromuscular dysplasia (young women, concomitant neurologic symptoms)
• Causes of hypertension and hypokalemia include mechanisms that lead to increased mineralocorticoid activity either through:
  • Increased RAAS activity in setting of hypoperfusion of kidneys due to renovascular disease
  • Primary hyperaldosteronism
  • Cushing syndrome (cortisol levels are so high that they begin to mimic mineralocorticoid activity)

47) A 32-year-old man comes to the emergency department because of swelling of his left hand and redness of his left…

Lymphangitis

• Young man with trauma to left hand presents with fever, leukocytosis and redness/swelling of left palm with streaky redness extending up forearm, concerning for cellulitis complicated by lymphangitis (likely due to Group A Strep)
• Key idea: Anything that breaches the skin barrier (trauma, burn, primary dermatologic condition, etc.) predisposes to infection
• Brown recluse spider bite –> Ulcerative/necrotic lesion
• Disseminated gonococcal infection –> Arthritis, pustular rash, tenosynovitis (pain with extending muscle sheathe)
• Erysipelas –> Well-defined, raised, erythematous infectious rash often on face/ears
• Sporotrichosis –> Patient pricked by a thorn/plant who presents with nodular ulcerative lesions in a lymphatic pattern

48) A previously healthy 25-year-old graduate student comes to the physician because of numbness of her left leg, stiffness of her right leg…

Spinal cord

• Young woman presents with acute onset of bilateral lower extremity weakness with upper motor neuron signs (positive Babinski, increased reflexes) on the right and loss of pinprick sensation below the level of T9 on the left, concerning for spinal cord lesion of the anterior right spinal cord near the T9 level (potentially due to an MS flare)
• Key idea: Corticospinal (motor) pathway crosses at the level of the medulla, whereas the spinothalamic tract (pain/temp) crosses within the spinal cord), such that a unilateral anterior spinal cord lesion will lead to ipsilateral UMN weakness and contralateral loss of pain/temperature
• Key idea: Dorsal column path (fine touch, proprioception) travels within the posterior portion of the spinal cord
• Key idea: Neurologic symptoms that begin at a specific dermatome and affect the dermatomes below it is a concerning history for a spinal cord lesion

49) A 32-year-old woman comes to the office for a follow-up examination. Six weeks ago, she was diagnosed with sinusitis…

Quantitative serum immunoglobulin testing

• Young woman with family history of uncle dying from pneumonia at a young age and personal history of recurrent bacterial sinopulmonary infections is found to have imaging findings concerning for chronic sinusitis and bronchiectasis, and therefore should be worked up for a B cell immunodeficiency through quantitative immunoglobulin testing
• Key idea: Most likely diagnosis in this case is common variable immunodeficiency, which is a B cell immunodeficiency that classically presents initially in adolescents or young adults rather than infancy/childhood)
• Key idea: B cell deficiencies classically present with recurrent bacterial and parasitic (Giardia) sinopulmonary and GI infections due to loss of IgG (opsonization of encapsulated bacteria), IgA (mucosal immunity) and IgE (parasitic defense)
• T cell deficiencies classically lead to fungal and viral infections primarily (think of HIV patients!)
• Other than immunodeficiencies, other diseases associated with bronchiectasis include cystic fibrosis and Kartagener’s syndrome because they can predispose to recurrent infections/inflammation within the lungs

50) A 47-year-old man with alcoholism is transferred from the hospital to a drug rehabilitation facility. On arrival, examination…

Hypomagnesemia

• Middle-aged man with alcoholism presents with hyperreflexia and tremor and is found to have hypocalcemia, and should have a magnesium level checked given that hypomagnesemia –> reduced PTH activity –> hypocalcemia
• Key idea: When a patient on the NBME is an alcoholic, you should immediately translate that into malnourished and consider nutritional deficiencies (B vitamin deficiencies [Wernicke encephalopathy, Pellagra, Folate deficiency], Scurvy, electrolyte derangements, etc.)

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1) A 77-year-old woman with osteoporosis and hypertension is admitted to the hospital because of progressive confusion…

Recurrence of breast cancer

• Elderly woman with history of breast cancer presents with acute confusion, constipation and a corrected calcium of 15.6 with multiple skull metastases on CT, most concerning for hypercalcemia in the setting of breast cancer metastatic to bone
• Key idea: Most common cause of hypercalcemia in the outpatient setting is hyperparathyroidism, whereas most common cause in the inpatient setting is malignancy (which is highest on differential whenever calcium > 14 or so)
• Corrected calcium = Measured calcium + 0.8 * (4.0 – albumin)
  • Albumin carries calcium, so if you have low albumin (less than normal of 4.0) it will make your serum calcium appear falsely low
• Hypercalcemia –> Stones (kidney stones), bones (bone pain), thrones (polyuria due to nephrogenic diabetes insipidus), groans (constipation and GI pain) and psychiatric overtones (anxiety, confusion, etc.)

2) A 62-year-old woman comes to the physician for a follow-up examination. Her blood pressure was 140/90…

Begin lisinopril therapy

• Middle-aged woman with diabetes mellitus presents with hypertension refractory to lifestyle changes and is found to have mild proteinuria, so should be immediately started on an ACE inhibitor or ARB in order to treat hypertension and, more importantly, slow progression of diabetic glomerulosclerosis
• Key idea: Diabetes leads to kidney disease by leading to preferential atherosclerosis of the efferent arteriole –> increased glomerular pressure –> chronic glomerular damage, and therefore the first sign of diabetic kidney disease is proteinuria rather than a drop in GFR (given early on diabetes will actually lead to an increase in GFR!)
• Key idea: ACE inhibitors and ARBs block angiotensin 2-mediated vasoconstriction of the efferent arteriole, and therefore basically counteract the renal effects of diabetes directly

3) A 23-year-old woman comes to the emergency department 2 hours after the sudden onset of sharp anterior chest pain…

Oral ibuprofen

• Young woman presents with acute sharp, pleuritic, chest pain and is found to have a friction rub with an ECG showing diffuse ST elevations and PR depressions, most consistent with pericarditis –> Best treatment is an NSAID such as ibuprofen
• Pleuritic chest pain differential:
  • Pericarditis
  • Pleuritis
  • Pneumothorax
  • Pulmonary embolus
• Common causes of pericarditis:
  • Post-viral
  • Uremia
  • Lupus erythematosus
  • Days after inflammation of heart (MI or CABG)
  • ~6 weeks after inflammation of heart (MI or CABG) due to Dressler syndrome
• Chest pain that is Positional, Pleuritic, sharP, and reproduced by Palpation reduces the likelihood it is related to cardiac ischemia

4) A 77-year-old man comes to the physician because of a 3-month history of intermittent mild abdominal pain…

Adverse effect of verapamil

• Elderly woman who started verapamil 4 months ago presents with 3 months of intermittent abdominal pain with signs of constipation (external hemorrhoid, hard stool in rectal vault, increased stool burden on imaging) most likely due to an adverse effect from verapamil (calcium channel blocker)
• Side effects of calcium channel blockers:
  • Constipation
  • Hyperprolactinemia
  • Gingival hyperplasia
  • Leg swelling
• Diabetic gastropathy –> Postprandial nausea, bloating and nausea

5) A 62-year-old man with severe obstructive pulmonary disease has chronic disabling dyspnea. His pulse is…

Severity of hypoxemia

• Middle-aged man with severe COPD presents with progressive dyspnea and is found to have distended jugular veins, loud S2 and prominent pulmonary arteries on chest x-ray, concerning for pulmonary hypertension in the setting of chronic, diffuse lung disease (cor pulmonale)
• Key idea: Most capillaries in the body vasodilate in the setting of hypoxia, with the one exception being the lungs in order to minimize V/Q mismatch. However, in the setting of diffuse lung hypoxia (obstructive or restrictive lung disease) –> Diffuse vasoconstriction of pulmonary capillaries –> Increased afterload faced by right ventricle –> Pulmonary hypertension with signs of right-sided heart failure (LEE, JVP, hepatomegaly) without signs of left-sided heart failure (lung crackles)
• Key idea: Classic features of pulmonary hypertension include loud S2 and apical heave (due to hypertrophied right ventricle being most anterior heart structure)

6) A 62-year-old woman comes to the physician 8 days after she had loss of consciousness while combing her hair…

Subclavian steal syndrome

• Middle-aged woman with atherosclerotic risk factors (hypertension, smoking) presents following intermittent episodes of loss of consciousness associated with exertion of her left arm and is found to have absent radial and brachial pulses on the left, concerning for peripheral artery disease complicated by subclavian steal syndrome
• Key idea: Basic pathophysiology is that stenosis of the left subclavian artery means that when the left arm is exerted, there will be vasodilation of the capillary beds (in the setting of hypoxia) and this will cause blood destined for the posterior circulation of the brain to flow in a retrograde fashion towards the left arm, leading to cerebral hypoperfusion with resulting syncope

7) A 42-year-old man comes to the emergency department because of the recent onset of shortness of breath. He has smoked two…

Anaerobic empyema

• Young man with 50 pack-year smoking history presents with acute respiratory distress and is found to have dullness to percussion of the right lung based, leukocytosis and a confirmed pleural effusion on CXR that is drained to yield purulent, foul-smelling fluid, concerning for a possible empyema
• Key idea: Fact that collection is located in the right lower lobe increases suspicion for empyema secondary to aspiration event, which should increase suspicion for an anaerobic empyema
• Key idea: Both Strep pneumo and Staph aureus are common causes of empyema, but they are often seen as complications of a preceding lobar pneumonia (which is not the case here)
• Key idea: Empyema is basically an abscess of the pleural space given it is a collection of purulent material, and just like an abscess of the skin needs to be treated with an incision and drainage, an empyema needs to be drained with a chest tube

8) A 53-year-old man notices a lump in his neck. Examination shows a hard 2-cm nodule in the lower left pole…

Administration of calcium gluconate intravenously

• Middle-aged man who undergoes total thyroidectomy and then shortly thereafter develops facial numbness and tingling with laryngeal stridor and a positive Chvostek sign, concerning for post-operative hypocalcemia due to damage/removal of nearby parathyroid gland(s) –> Best immediate treatment is calcium gluconate to treat/reverse hypocalcemia
• Key idea: Endotracheal intubation not indicated given lack of shortness of breathe or hypoxia (hoarseness and stridor likely due to spasms in setting of hypocalcemia)
• Key idea: Hypocalcemia is a COMMON complication of thyroid surgery given the parathyroids lie very close to the thyroid gland (as the name implies)

9) A previously healthy 24-year-old woman comes to the physician because of an itchy rash on her face…

Inflammation caused by release of cytokines by effector and memory T lymphocytes

• Young woman presents with pruritic urticarial and vesicular rash of the face, upper extremities and hands 2 days after working in her garden, concerning for a possible contact dermatitis, which is a classic Type 4 hypersensitivity reaction (mediated by T cells)
• Common triggers of contact dermatitis:
  • Poison oak/ivy
  • Nickel
  • Topical antibiotics
  • Hair dyes
  • Soaps/detergents
• Key idea: For the NBME exam, vesicular eruptions should make you think of viral infection (HSV, VZV, etc.), dermatitis herpetiformis and eczematous rashes (contact dermatitis, atopic dermatitis, etc.)
• Destruction of adhesion among epidermal cells caused by circulating IgG autoantibodies –> Pemphigus vulgaris –> Paraneoplastic syndrome characterized by widespread painful flaccid bullae/blisters with mucosal involvement

10) A 62-year-old woman comes to the physician because of increasingly severe pain of the fingers over the past…

Positive findings for anticentromere antibody

• Middle-aged woman presents with chronic history of Raynaud’s syndrome, GERD, tightening of the skin, telangiectasias, and soft tissue calcifications, with this constellation of symptoms being concerning for CREST syndrome (localized scleroderma) which is characterized by anticentromere antibodies
• CREST syndrome:
  • Calcinosis cutis (soft tissue calcifications)
  • Raynaud’s syndrome (cold exposure causing hands to turn white–>blue–>red)
  • Esophageal dysmotility (dysphagia, GERD)
  • Sclerodactyly (tight, shiny skin on the fingers)
  • Telangiectasias
• On the NBME, lung crackles should make you concerned for pulmonary edema or interstitial lung disease (which is more likely in this case given association with scleroderma)
• Note: Diffuse scleroderma characterized by Anti-Scl-70 antibodies (anti-DNA topoisomerase I)
• Antineutrophil cytoplasmic antibody = C-ANCA = Granulomatosis with polyangiitis = Upper respiratory disease (nasal ulcers, ear ulcers) + Lower respiratory disease (hemoptysis) + Renal disease (glomerulonephritis)
• Anti-double stranded DNA –> Lupus
• Antiribonuclear antibody –> Mixed connective tissue disease –> Features of polymyositis, scleroderma and lupus

11) A 32-year-old man is brought to the emergency department 30 minutes after he was found unconscious on the floor…

Rhabdomyolysis

• Young man found down in setting of barbiturates overdose is found to have significantly elevated creatine kinase, hyperkalemia, metabolic acidosis, significant AKI with BUN:Creatinine ratio less than 15 and urinalysis notable for pigmented granular casts and positive dipstick for blood with few RBCs on microscopy, all of which points to rhabdomyolysis complicated by acute tubular necrosis
• Key idea: Rhabdomyolysis classically leads to positive urine dipstick for blood with no/few RBCs on urine microscopy because the dipstick test can return false positives in the setting of myoglobinuria (and hemoglobinuria)
• Key idea: BUN:Creatinine ratio greater than 20 points to pre-renal etiology (renal hypoperfusion), whereas a BUN:Creatinine ratio less than 15 points to an intrarenal etiology (acute tubular necrosis, acute interstitial nephritis, glomerulonephritis)
• Causes of rhabdomyolysis:
  • Increased muscle exertion (seizure, exercise)
  • Immobilization or crush injury
  • Medications/toxins (statins, alcohol, etc.)
• Causes of Acute tubular necrosis:
  • Severe ischemia (necrosis)
  • Rhabdomyolysis
  • Contrast nephropathy
  • Heavy metals
  • Aminoglycosides (gentamicin)
  • Ethylene glycol
  • Tumor lysis syndrome
• Acute interstitial nephritis –> Patient started on new drug (PPI, antibiotic, diuretic, NSAID) and then develops rash + fever + AKI with eosinophils and/or WBC casts in urine
• Glomerulonephritis –> Proteinuria and hematuria with RBC casts and/or dysmorphic RBCs

12) A 62-year-old man comes to the physician because of a 3-week history of progressive fatigue and shortness of breath…

Lisinopril

• Middle-aged man presents with subacute exertional shortness of breath and is found to have symptoms concerning for heart failure (bilateral basilar crackles, laterally displaced point of maximal impulse, decreased ejection fraction) and would therefore benefit from furosemide and an ACE inhibitor (lisinopril)
• Key idea: Medications shown to improve long-term survival among individuals with heart failure include ACE inhibitor or ARB, beta-blockers (carvedilol, metoprolol succinate, bisoprolol) and aldosterone antagonists (spironolactone), with ACE inhibitors often looked upon most favorably in the setting of acute decompensated heart failure (such as this patient who is volume overloaded)
• Note: Spironolactone is the first-line diuretic among patients with volume overload in the setting of cirrhosis

13) A 26-year-old man is brought to the emergency department after vomiting bright red blood twice…

Intravenous administration of 0.9% saline

• Young man presents following two episodes of hematemesis (potentially in setting of Mallory-Weiss tear) and is found to be tachycardic with low-normal blood pressure, and therefore would likely benefit from some fluid resuscitation with 0.9% normal saline
• Key idea: In all patients, first priority is the ABCs of Airway (can patient protect airway?), Breathing (is patient breathing normally?), and Circulation (does patient seem well-perfused?)
• Key idea: Fluid resuscitation should always be performed with an isotonic fluid such as 0.9% normal saline and lactated ringers
• Key idea: In setting of acute blood loss, the hematocrit/hemoglobin may initially appear normal given they are concentration measures rather than absolute measures

14) A 24-year-old woman has had intermittent fever, malaise, and a generalized rash for 2 weeks. Her temperature is 37.2 C…

Jarisch-Herxheimer reaction

• Young woman presents with fever, generalized maculopapular rash over palms and soles and patchy alopecia (concerning for syphilis). She receives treatment with penicillin G and then shortly thereafter develops chills, headache, tachycardia, flushing and fever, concerning for the Jarisch-Herxheimer reaction
• Key idea: Jarisch-Herxheimer reaction commonly seen soon after initiating treatment for spirochete infections (syphilis, lyme disease, etc.) and occurs due to the release of endotoxin-like substances from microorganisms as they are killed
• Meningococcemia –> Fever, neck stiffness, photophobia, petechial/purpuric rash
• Rocky Mountain spotted fever –> Fever, myalgias, confusion, petechial/purpuric rash starting on palms/soles and spreading to body
• Toxic shock syndrome –> Patient with nasal packing or prolonged tampon usage who presents with fever, hypertension and diffuse erythroderma

15) A 47-year-old man comes to the physician because of a 1-month history of progressive swelling of both legs and generalized…

Renal biopsy

• Middle-aged man with history of IVDU and chronic hepatitis B and C presents with subacute lower extremity edema and is found to be hypertensive with significant proteinuria and hematuria, concerning for a possible glomerulonephritis that should be worked up with a renal biopsy
• Key idea: Chronic hepatitis infections associated with cryoglobulinemia and membranoproliferative glomerulonephritis, both of which can lead to glomerulonephritis
• Urine protein electrophoresis –> Multiple myeloma –> Hypercalcemia, back pain, anemia, renal disease
• Cystoscopy –> Unexplained hematuria or urinary symptoms in a smoker (looking for bladder cancer)

16) A previously healthy 37-year-old woman comes to the physician because of a 2-year history of progressive shortness of breath…

Insufficient inhibition of neutrophil elastase

• Young woman with 5 pack-year smoking history and a family history of emphysema development at a young age presents with progressive dyspnea and wheezing and is found to have a low FEV1 on pulmonary function tests and CXR showing hyperinflated lungs, concerning for alpha-1 antitrypsin deficiency complicated by COPD
• Key idea: Neutrophil elastase is a protease that can lead to breakdown of alveoli and is typically inhibited by the anti-protease enzyme alpha-1 antitrypsin, so patients who lack alpha-1 antitrypsin will have accelerated destruction of alveoli (especially in setting of tobacco use) –> early-onset COPD
• Key idea: Alpha-1 antitrypsin classically leads to early-onset COPD and cirrhosis without significant exposures to the typical risk factors
• Key idea: Obstructive lung diseases are due to problems getting air out (i.e., decreased elasticity of lungs or highly turbulent airflow upon expiration) and therefore lead to hyperinflated lungs (asthma, COPD, bronchiectasis)
• Key idea: Restrictive lung diseases are due to problems getting air in (i.e., lungs are excessively stiff or diaphragm is weak) and therefore leads to small lungs (interstitial lung diseases, neuromuscular weakness, etc.)

17) A 24-year-old woman, gravida 2, para 2, comes to the emergency department because of an uncontrollable nosebleed…

Corticosteroid therapy

• Young woman presenting with recurrent mucosal bleeding and petechiae (both concerning for a platelet problem) is found to be thrombocytopenic with megakaryocytes in the bone marrow, most consistent with immune thrombocytopenic purpura (i.e., platelets are being produced but then being destroyed by circulating antibodies)
• Key idea: First line treatment of ITP is corticosteroids, followed by IVIG, and lastly splenectomy if the patient is highly refractory (eliminates primary source of antibody production and destruction)
• Key idea: If patient has clinical aspects of a platelet disorder (mucosal bleeding, petechiae, etc.), then first branch point is whether they have a Quantitative or Qualitative platelet disorder:
  • Quantitative(decreased platelet count, prolonged bleeding time)
    • Immune thrombocytopenic purpura: Often seen in young people (autoimmune disease), leads to isolated thrombocytopenia (unless it’s a component of SLE)
    • Aplastic anemia: Pancytopenia, often associated with cancer or prior radiation
  • Qualitative(normal platelet count, prolonged bleeding time)
    • Uremia: Indication for dialysis!
    • von Willebrand disease: Often presents since childhood/adolescence, may have mildly prolonged aPTT given vWF is a carrier protein for Factor 8

18) A 52-year-old woman comes for a routine health maintenance examination. She feels well. Over the past 6 months…

Weight loss

• Key idea: Two most important risk factors for osteoarthritis are advanced age (non-modifiable) and obesity (modifiable)

19) A 62-year-old man comes to the physician for a preoperative evaluation. He is scheduled to undergo partial colectomy…

No further tests are indicated

• Middle-aged man scheduled for an impending partial colectomy has evidence of mild aortic stenosis and mild mitral regurgitation, but has no symptoms of ischemic heart disease (i.e., chest pain or dyspnea brought on by exertion that is relieved by rest or nitrates) and therefore does not require further cardiac work-up prior to surgery

20) A 57-year-old man comes to the emergency department because of a painful, cold right leg for 4 hours…

Hydration

• Middle-aged man with atherosclerotic risk factors presents with an acutely painful and cold leg and has an angiography of the right leg performed that is complicated by a significant increase in creatinine. This picture is concerning for contrast nephropathy, with the risk of this complication being decreased by hydration prior to the imaging procedure
• Key idea: Many cases of contrast nephropathy will self-resolve, but in serious cases can progress to acute tubular necrosis
• Pretreatment with prednisone and diphenhydramine –> Reduces risk of urticarial and anaphylactic drug reactions
• Discontinuation of metformin often performed in hospitalized patients due to risk of lactic acidosis (AG metabolic acidosis)

21) A 67-year-old man with type 2 diabetes mellitus comes to the physician because of a 2-day history of increasing pain and redness…

Prepatellar septic bursitis

• Elderly man who recently spent significant time on his knees presents with acute progressive pain and redness of his left knee and fever, with exam demonstrating fluctuance ANTERIOR to the patella that is concerning for prepatellar bursitis
• Key idea: Next best step would be bursal fluid aspiration, with treatment either being NSAIDS in setting of uncomplicated disease versus drainage and systemic antibiotics in setting of complicated disease
• Inflamed Baker cyst –> Erythema, swelling and pain BEHIND the knee
• Inflammatory bursitis of the pes anserinus –> Erythema, swelling and pain of the PROXIMAL MEDIAL SHIN
• Osgood-Schlatter disease –> Adolescent with pain and bony protuberance over the ANTERIOR PROXIMAL TIBIA

22) A 52-year-old woman with hypertension and type 2 diabetes mellitus is admitted to the hospital because of a…

Acyclovir

• Middle-aged woman presents with acute progressive confusion and fever with brain MRI demonstrating temporal lobe hemorrhage/edema concerning for HSV encephalitis –> Treat with acyclovir
• Key idea: HSV specifically leads to temporal lobe disease because it primarily results from oropharyngeal infection that travels via the olfactory tract to the olfactory cortex, which is located in the temporal lobe
• Encephalitis: Fever + Altered mental status
• Meningitis: Fever + meningismus (stiff neck, headache) + photophobia
• Ceftriaxone –> Bacterial meningitis
• Dexamethasone –> Brain tumor
• Low-molecular-weight heparin –> Stroke
• Mannitol –> Significant brain edema
• Pyrimethamine-sulfadiazine –> Toxoplasmosis (ring-enhancing lesion in immunocompromised patient)

23) Two days after a myocardial infarction, a previously asymptomatic 60-year-old woman develops pulmonary edema…

Ruptured papillary muscle

• Middle-aged woman who develops acute pulmonary edema and a systolic murmur over the apex 2 days after an MI, concerning for papillary muscle rupture c/b mitral regurgitation
• Key idea: Post-MI complications involving rupture (papillary muscle, free wall, interventricular septum) often occur 2-5 days after MI because that is when those structures would be most damaged and most prone to rupture
• Key idea: Papillary muscle rupture most commonly seen following an inferior MI (leads 2, 3 and aVF) because the right coronary artery feeds the posteromedial papillary muscle
• Key idea: Slow onset mitral regurgitation can often be tolerated by the heart, but the heart (and basically every other part of the body) does not respond well to an acute change in demand/stress, leading to flash pulmonary edema
• Holosystolic apical murmur over apex radiating to axillae –> Mitral regurgitation
• Diastolic murmur over apex –> Mitral stenosis
• Systolic ejection murmur in upper sternal border radiating to carotids –> Aortic stenosis
• Decrescendo diastolic murmur in upper sternal border –> Aortic regurgitation

24) A 47-year-old woman comes to the physician because of a 2-day history of soreness in the back of her throat and pain…

Airway compromise

• Middle-aged woman with history of recurrent episodes of tonsillitis presents with odynophagia with massive edema and purulence of the soft palate and tonsils, putting patient at increased risk for airway compromise
• Common indications for intubation:
  • Expanding hematoma, swelling or emphysema in neck (risk of airway obstruction)
  • Glasgow-Coma score of 8 or less (eight and intub-eight) [risk of not protecting airway]
  • Severe inhalation injury (i.e., breathing smoke during house fire)
  • Breathing is noisy or gurgly

25) An asymptomatic 32-year-old woman with HIV infection comes to the physician as a new patient. Her last…

Pap smear and P. jiroveci prophylaxis

• Key idea: Patients with HIV should receive an annual pap smear (given immunocompromise –> chronic HPV infection –> increased risk of cervical CA)
• CD4 < 200 –> TMP-SMX for PJP/PCP prophylaxis
• CD4 < 100 –> TMP-SMX for toxoplasmosis prophylaxis
• CD4 < 50 –> Azithromycin for Mycobacterium avium complex (MAC) prophylaxis
• Mammography –> Every 2 years starting at 50 years old

26) A 62-year-old woman has had progressively severe midback pain over the past month. She has been fatigued and…

Serum protein electrophoresis

• Middle-aged woman with subacute back pain and confusion is found to have anemia, hypercalcemia and renal dysfunction with lateral skull x-ray showing dark, osteolytic lesions most concerning for multiple myeloma –> work-up with serum protein electrophoresis (SPEP)
• Key idea: Whenever you see the combination of hypercalcemia and renal dysfunction you should think of multiple myeloma given that renal dysfunction typically leads to hypocalcemia (decreased vitamin D activation and increased circulating phosphate to bind up calcium)
• Key idea: Patients with multiple myeloma will very commonly be anemic given that the over production of plasma cells occurs in the bone marrow and would impede normal RBC production

27) A previously healthy 52-year-old man comes to the physician because of a 6-month history of cough productive of…

Alveolar destruction and fibrosis

• Middle-aged man with 25 pack-year smoking history presents with chronic cough and is found to have prolonged expiratory phase with an FEV1:FVC ratio less than 0.7, consistent with an obstructive lung disease such as COPD which is caused by alveolar destruction
• Key idea: Obstructive lung diseases occur when there is trouble getting air out of the lungs, which can happen in COPD because patients have destruction of their alveoli and the alveoli are what provide elasticity of the lung and help the lungs collapse inward during expiration
• Diffuse infiltrative disease of the lung parenchyma –> Interstitial lung disease –> Restrictive lung disease (decreased lung volumes)

28) A 35-year-old man had recurrent episodes of dysuria and pelvic pain over the past 2 years. He is sexually…

Chlamydia trachomatis

• Young sexually active man presents with recurrent episodes of dysuria and pelvic pain and is found to have prostate tenderness and sterile pyuria (WBCs in urine with negative urine culture), concerning for chronic prostatitis
• Key idea: Prostatitis in a young man (<35 years old) is often due to Chlamydia or Neisseria gonorrhea, whereas prostatitis in an older man (>35 years old) is often due to Gram negative bacteria (such as E. coli)
• Key idea: Sterile pyuria (positive WBCs in urine but negative urine culture) is classically seen in cervicitis (in women), chronic prostatitis (in men) and urethritis (both)
• Chancroid –> Painful ulcerative genital lesion
• Herpes simplex –> Painful vesicular genital lesions or shallow ulcers
• Syphilis –> Painless genital ulcer (chancre) + lymphadenopathy

29) A 37-year-old woman with type 1 diabetes mellitus and anxiety disorder comes to the physician because of a 6-month…

Syringomyelia

• Young woman presents with chronic progressive loss of pain and temperature sensation over forearms, hands and upper back with increased deep tendon reflexes globally, concerning for a possible syringomyelia
• Key idea: Syringomyelia is a cystic cavity within the central canal of the spinal cord and classically leads to loss of pain and temperature sensation in a “cape-like” distribution over the bilateral arms and upper back because it blocks the spinothalamic fibers from crossing over within the spinal cord
• Note: Does not lead to motor symptoms or loss of fine touch/proprioception because those fibers cross in the medulla rather than within the spinal cord
• Key idea: Syringomyelia classically associated with Chiari 1 malformations, trauma and tumors

30) A 32-year-old woman comes to the emergency department because of fever and cough with increasing production…

Allergic bronchopulmonary aspergillosis

• Young woman with atopic history presents with recurrent episodes of fever, cough and purulent sputum associated with a poorly resolving lung infiltrate and is found to have Aspergillus fumigatus on sputum culture, concerning for allergic bronchopulmonary aspergillosis
• Aspergillosis can lead to several distinct pulmonary pathologies:
  • Allergic bronchopulmonary aspergillosis: Patient with asthma or cystic fibrosis who presents with recurrent fleeting infiltrates associated with eosinophilia due to hypersensitivity response to Aspergillus; treat with months of itraconazole and oral steroids
  • Angioinvasive aspergillosis: Immunocompromised patient who presents with fever, chest pain and hemoptysis with imaging demonstrating a halo sign (ground glass opacity surrounding nodule); treat with voriconazole and caspofungin
  • Chronic pulmonary aspergillosis: Patient with history of cavitary lung disease (tuberculosis, aspiration, Klebsiella) who presents with chronic weight loss, cough and hemoptysis and is found to have a cavitary lung lesion with a fungal ball (aspergilloma); treat with surgical resection +/- azole medication
• Cystic fibrosis –> Recurrent sinopulmonary infections + Fat malabsorption with weight loss + Bronchiectasis
• Alpha-1 antitrypsin deficiency –> COPD and cirrhosis in a young patient with family history
• Pertussis –> 1-2 weeks of cold-like symptoms followed by intermittent bouts of violent coughing (post-tussive vomiting, subconjunctival hemorrhages, etc.)

31) A 52-year-old woman has decreased urine output 6 hours after admission for treatment of a 3-day history…

Acute tubular necrosis

• Middle-aged woman with possible diabetic gastroparesis presents with nausea/vomiting complicated by hypotension and is found to have an acute increase in her creatinine with coarse granular casts concerning for possible acute tubular necrosis
• Key idea: Hypotension/dehydration will often initially lead to a pre-renal acute kidney injury, but in setting of severe or prolonged hypotension/dehydration patients can develop acute tubular necrosis (form of intrarenal acute kidney injury)
• Note: Typical way to differentiate between pre-renal AKI vs ATN is by looking at BUN:Cr ratio (often >20 in pre-renal AKI and <15 in intra-renal AKI) and presence of granular (“muddy brown”) casts that is suggestive of acute tubular necrosis
• Acute glomerulonephritis –> Proteinuria and hematuria with RBC casts and/or dysmorphic RBCs
• Acute interstitial nephritis –> Patient started on a new medication (antibiotic, diuretic, PPI, NSAID) who presents with fever + rash + AKI
• Rhabdomyolysis –> Positive dipstick for blood with no/few RBCs on microscopy (due to myoglobinuria leading to false-positive dipstick) with elevated creatine kinase, hyperkalemia and hyperphosphatemia

32) A 37-year-old man comes to the emergency department because of vomiting for the past 3 days. He says that he cannot hold…

Decreased K+, Decreased Cl- and Increased pH

• Young man with recurrent vomiting with dry mucous membranes who will likely have a hypokalemic, hypochloremic, metabolic alkalosis due to recurrent vomiting
• Key idea: Patients with excessive vomiting develop hypochloremia and metabolic alkalosis because they are losing stomach acid (which is HCL = H+ with Cl-)
• Key idea: Patients with excessive vomiting –> hypovolemic –> RAAS overactivation –> Increased aldosterone activity –> Increased reabsorption of Na+ from collecting duct in exchange for K+ and H+ –> Contraction alkalosis with hypokalemia

33) A 62-year-old man is admitted to the hospital for treatment of pneumonia. He has a 3-day history of fever…

Metformin

• Middle-aged man with history of type 2 diabetes mellitus and coronary artery disease is admitted for pneumonia with labs concerning for an anion gap metabolic acidosis, and should therefore have his metformin discontinued due to risk of lactic acidosis in setting of sepsis/hypotension
• Anion gap = [Na+] – [Cl-] – [HCO3-], with an AG >12 being consistent with an anion gap metabolic acidosis
• Differential for anion gap metabolic acidosis [MUDPILERS]:
  • Methanol (associated with ocular/eye symptoms)
  • Uremia
  • DKA
  • Propylene glycol
  • Isoniazid/Iron
  • Lactic acidosis
  • Ethylene glycol (associated with kidney disease)
  • Rhabdomyolysis
  • Salicylate toxicity (early respiratory alkalosis –> anion gap metabolic acidosis can lead to a normal overall pH)

34) A 57-year-old man comes to the physician because of a 3-month history of mild shortness of breath with exertion…

Switch from glyburide and metformin to intermediate-acting insulin

• Middle-aged man with history of type 2 diabetes treated with oral medication (metformin, glyburide) presents with chronic exertional shortness of breathe and is found to have hypertension and a hemoglobin A1c > 9%, meaning they could probably benefit from addition of basal insulin
• Key idea: Goal HgbA1c in patients with type 2 diabetes is below 7%, but often a level 8% is tolerable especially in older patients where the risks of hypoglycemia carry more weight
• Step-up therapy for diabetes management:
  • 1st: Lifestyle changes
  • 2nd: Metformin
  • 3rd: Metformin + Oral antidiabetic agents (glipizide) or GLP-1 analogue (exenatide)
  • 4th: Metformin + basal insulin
  • 5th: Basal-bolus insulin therapy

35) A 55-year-old woman comes to the emergency department because of fever, nausea, vomiting, diarrhea, and decreased…

Prerenal azotemia

• Middle-aged woman with acute vomiting and diarrhea presents with decreased urine output and is found to have orthostatic hypotension, tachycardia, and dry mucous membranes with a BUN:Creatinine ratio >20 and urine Na+ level < 20, both of which are compatible with pre-renal AKI
• Key idea: Hypotension/dehydration can lead to either a pre-renal AKI or acute tubular necrosis (form of intra-renal AKI) with a pre-renal AKI being favored if urine concentrating functions of the kidney appear preserved, which is suggested by BUN:Cr ratio > 20, urine Na+ < 20 and a FeNa < 1% because these lab findings all suggest Na+ is being reabsorbed effectively to try to preserve volume status
• Note: Orthostatic hypotension diagnosed if a patient moves from lying to sitting or sitting to standing and has a drop in systolic BP of at least 20 mm Hg and/or a drop in diastolic BP of at least 10 mm Hg

36) A 42-year-old man with alcoholism is admitted to the hospital 12 hours after the onst of severe epigastric pain that…

Serum calcium concentration

• A young man with alcohol use disorder presents with symptoms concerning for acute pancreatitis (epigastric pain radiating to back with amylase at least 3X above upper limit of normal), with patient’s hypocalcemia portending a poor prognosis
• Key idea: Hypocalcemia in the setting of acute pancreatitis is indicative of a high degree of fat saponification in the setting of fat necrosis of peripancreatic fat and carries a poor prognosis both because it indicates significant disease burden and because hypocalcemia can lead to additional morbidity
• Key idea: Two most common causes of pancreatitis are alcohol and gallstones, and therefore if patient denies alcohol use then next best step is right upper quadrant ultrasound to look for gallstones (HIGH YIELD!!!); if RUQ U/S is negative, next set of lab tests would be calcium level and lipid studies (looking for hypertriglyceridemia)
• Full differential for pancreatitis remembered by I GET SMASHED:
  • Idiopathic
  • Gallstones
  • EtOH
  • Trauma (motor vehicle accident, hitting stomach on bike handles, etc.)
  • Steroids
  • Mumps (parotitis, pancreatitis and orchitis)
  • Autoimmune
  • Scorpion sting
  • Hypertriglyceridemia/Hypercalcemia
  • ERCP
  • Drugs (diuretics, HIV drugs, etc.)

37) A 62-year-old man comes to the physician because of moderate right leg pain for 2 days. He has metastatic non-small cell…

Subcutaneous administration of enoxaparin

• Middle-aged man with known history of lung cancer presents with moderate right leg pain with a positive DVT ultrasound –> best treatment is heparin (enoxaparin)
• Key idea: Thrombolytics (alteplase) are only given in a patient with DVT and signs/symptoms concerning for a PE (chest pain, dyspnea, hypoxia, tachycardia)
• Key idea: Patients are initially given heparin and then bridged to warfarin to reduce likelihood of warfarin-induced skin necrosis due to selective inhibition of proteins C and S (anti-thrombotic proteins) seen with initial warfarin administration
• Key idea: IVC filters are generally unfavored given they can become infected or become a nidus for clot formation and are typically only reserved for patients for whom anticoagulants are contraindicated (history of massive GI bleed, hemorrhagic stroke, etc.)

38) A previously healthy 22-year-old man is brought to the emergency department 1 hour after he was hit in his right flank…

No further testing is indicated

• Key idea: Patient has stable hematocrit, no rebound/guarding, stable vitals and no urinary changes
• Key idea: Patients with flank trauma who develop hematuria, severe flank tenderness and expanding flank ecchymosis should receive a CT scan

39) A 24-year-old woman, gravida 1, para 1, comes to the physician because of a 3-month history of fatigue. Menses occur…

Iron

• Young woman with normal menses presents with chronic fatigue, pale conjunctivae, anemia and blood smear demonstrating hypochromic RBCs most consistent with iron deficiency anemia
• Key idea: Most common cause of shortness of breathe and anemia in young women is iron deficiency anemia in setting of menstrual blood losses (even if menses are normal)
• Hypochromic RBCs –> Enlarged areas of central pallor
• Folate deficiency –> Megaloblastic anemia (MCV > 100 with hypersegmented neutrophils (5+ nuclear lobes))
• Niacin deficiency –> Pellagra (Diarrhea, Dermatitis, Dementia)
• Thiamine deficiency –> Wernicke encephalopathy (confusion, ataxia, ophthalmoplegia)
• Vitamin B6 (pyridoxine) deficiency –> Peripheral neuropathy, almost exclusively seen among patients receiving isoniazid for mycobacterial infection

40) A moderately obese 35-year-old woman has a 4-year history of recurrent abscesses in both axillae. These are…

Surgical excision of apocrine tissue

• Young obese woman with chronic history of recurrent painful abscesses in both axillae concerning for hidradenitis suppurativa –> Definitive treatment includes surgical removal of apocrine glands given that disease originates from the apocrine glands
• Key idea: Two most important risk factors for hidradenitis suppurativa include obesity and tobacco use

41) A 37-year-old woman comes to the physician because she has been amenorrheic for 3 months. She has also had…

Urine free cortisol concentration in a 24-hour specimen

• Young woman presents with chronic history of secondary amenorrhea, hirsutism, massive weight gain, hypertension, and truncal obesity concerning for Cushing syndrome, which can be diagnosed by:
  • Increased 24-hour urine free cortisol
  • Increased late night salivary cortisol
  • Inadequate low-dose (1 mg) overnight dexamethasone suppression test
• Key idea: After Cushing syndrome is diagnosed, next best test is ACTH level because that can tell you whether you’re dealing with ACTH-dependent forms of Cushing syndrome due to ACTH-producing pituitary tumor (Cushing disease) or ACTH-producing tumor elsewhere (small cell carcinoma), or whether you’re dealing with ACTH-independent forms of Cushing syndrome such as exogenous steroid usage or adrenal hyperplasia/carcinoma
• Note: Elevated DHEA SULFATE is indicative of increased androgen production from the adrenal glands and is often concerning for adrenal hyperplasia or adrenal carcinoma (which can lead to ACTH-independent form of Cushing syndrome)

42) A 67-year-old white man comes to the physician because his wife is concerned about a freckle on the back of his neck…

Full thickness biopsy

• Elderly white man presents with changing, multi-colored, large (>6 mm), asymmetric pigmented lesion with unclear borders, concerning for a possible melanoma that should be worked up with a full thickness biopsy
• Key idea: Concerning features of pigmented lesions can be remembered by ABCDE‘s:
  • Asymmetric
  • Unclear/irregular Borders
  • Multiple Colors
  • Diameter > 6 mm
  • Evolution
• Key idea: Shave biopsy is NOT appropriate in the setting of possible melanoma because you want to assess depth of invasion (Breslow thickness) in order to determine appropriate margins for full excision

43) A 77-year-old man is brought by his wife for a follow-up examination 3 weeks after an episode of right middle lobe pneumonia…

Swallowing study

• Elderly man with history of vascular dementia, MMSE of 20 and recent right middle lobe pneumonia endorses increased coughing after meals with dysarthria on exam, concerning for possible oropharyngeal dysphagia that should be worked up with a swallowing study
• Key idea: Aspiration tends to predominately affect the right lung given that the right mainstem bronchus is shorter, wider and more vertical than the left mainstem bronchus
• Two main forms of dysphagia include:
  • Oropharyngeal dysphagia: Difficulty initiating swallowing associated with coughing choking, aspiration or nasal regurgitation
    • Often secondary to stroke, dementia, oropharyngeal malignancy or neuromuscular disorder
    • Work-up with videofluoroscopic modified barium swallow (swallow study)
  • Esophageal dysphagia: Sensation of food getting stuck in esophagus a few seconds after swallowing
    • Dysphagia to solids and liquids –> Likely motility issue –> Barium swallow or esophageal manometry
    • Dysphagia to solids progressing to liquids –> Likely esophageal obstruction (malignancy, stricture, esophageal web) –> Upper endoscopy >> Barium swallow
• Dementia should be suspected in patient with MOCA < 26 and/or MMSE < 24

44) A 77-year-old woman comes to the physician because of a 3-weekhistory of light-headedness. She states that she feels…

Ambulatory ECG monitoring

• Elderly woman with subacute history of light-headedness upon standing who is found to have an irregularly irregular heart rate with EKG confirmed atrial fibrillation and no orthostatic hypotension who would benefit from home/ambulatory ECG monitoring to make sure she is not having bouts of Afib with rapid ventricular rate or another more malignant rhythm
• Key idea: Her history of dizziness upon standing sounded like potential orthostatic hypotension, but she did not meet criteria (systolic BP drop > 20 mm Hg or diastolic BP drop > 10 mm Hg upon moving from sitting to standing)
• Syncope is caused by hypoperfusion of the brain, with potential causes including vasovagal and carotid hypersensitivity, hypovolemia, or problems with the heart pumping blood forward (impaired contractility, arrhythmia, severe aortic stenosis or outflow obstruction, etc.)
• Exercise stress test –> Most useful in setting of potential cardiac ischemia (exertional chest pain or dyspnea)

45) A 32-year-old man comes to the physician because of a 4-week history of moderate numbness and weakness of his left hand…

Ulnar nerve compression

• Young man with subacute numbness and weakness of his left hand with atrophy of the hypothenar muscles and “claw hand” deformity of fingers 3, 4 and 5 with weak finger abduction and decreased sensation over the palmar aspects of fingers 4 and 5, most concerning for an ulnar nerve compression
• Key idea: Ulnar nerve is most commonly compressed at the elbow (person working at computer or truck driver putting pressure on elbow all day), but the presence of an ulnar claw points to compression at the wrist (loss of proximal finger extensors with intact distal finger flexors)
• Key idea: C8 nerve root provides similar sensory input as the ulnar nerve, but is primarily responsible for finger flexion so a C8 nerve root compression would lead to loss of finger flexion rather than an “ulnar claw” (where fingers are permanently flexed)

46) A study is conducted to compare a new stool test with mucosal biopsy for diagnosing Helicobacter pylori infection...

80%

• https://www.youtube.com/watch?v=LEIVLFYiVSY&list=PL6qsoERoF8MBym_g1bIVOIzLOIXnOBqJp

47) A 72-year-old man comes to the physician for a routine examination. He has a 1-year history of hypertension controlled…

Cigarette smoking

• Key idea: #1 risk factor for atherosclerotic diseases is cigarette smoking, followed by diabetes
• Key idea: #1 risk factor for stroke is hypertension
• Key idea: Increased weight is #1 risk factor for osteoarthritis

48) A previously healthy 27-year-old intern comes to the emergency department 5 minutes after she was stuck in the…

Washing the area of involvement

• Young woman immunized against hepatitis B was stuck by a needle used on a patient with AIDS who has labs demonstrating they do not have active hepatitis B, and therefore should carefully wash the area of involvement and then start post-exposure prophylaxis against HIV within 72 hours (but the earlier the better!)
• Key idea: Young woman is immunized against hepatitis B and the patient did not have active hepatitis B, so no post-exposure prophylaxis against hepatitis B is needed
• Note: If a patient is stuck with a needle used on a patient with hepatitis C, no post-exposure prophylaxis is indicated given there are no effective agents and the risk of transmission is very low

49) A 72-year-old woman comes to the physician because of a 6-day history of increasingly severe left hip pain. She now has difficulty…

Avascular necrosis

• Elderly woman currently taking prednisone who presents with increasingly severe left hip pain with significant pain with weight bearing and hip MRI demonstrating crescent sign of left hip, most consistent with avascular necrosis due to steroid use
• Key idea: Hip pain with inability to bear weight often makes me think of avascular necrosis or septic arthritis (if patient is also febrile)
• Causes of avascular necrosis can be remembered by CAST Bent LeGS:
  • Corticosteroids
  • Alcoholism
  • Sickle cell disease
  • Trauma
  • “the Bends” –> Rising too quickly while deep sea diving –> precipitation of air bubbles that can occlude blood vessels
  • Legg-Calve Perthes –> Idiopathic avascular necrosis of the hip seen in 5-7 year olds
  • Gaucher disease (lysosomal storage disease with similar features to sickle cell disease)
  • Slipped capital femoral epiphysis (SCFE) –> Overweight adolescent

50) A healthy 39-year-old man of German descent comes for a routine examination. He had a cholecystectomy at the age of 25…

Abnormal red blood cell membrane

• Young man of European descent with history of cholecystectomy at young age and intermittent jaundice presents with splenomegaly and normocytic anemia with increased mean corpuscular hemoglobin concentration (MCHC), negative Coombs test and spherocytes (erythrocytes with loss of central pallor), all of which point towards hereditary spherocytosis (due to abnormal red blood cell membrane)
• Key idea: Spherocytes can be seen in hereditary spherocytosis and autoimmune hemolytic anemia, with the key distinguishing factor being the Direct Coombs test
• Key idea: Increased MCHC is a fairly specific finding for hereditary spherocytosis
• Key idea: Most commonly seen in patients of Northern European descent with family history of splenectomy (autosomal dominant condition), and commonly leads to biliary pathologies due to chronic hemolysis leading to pigment gallstones
• Treatment: Folate supplementation (due to chronic hemolysis) + Splenectomy (given that cells are being destroyed in the spleen)

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