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NBME Medicine Form 5

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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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