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1) A 3-year-old girl is brought to the physician by her mother, who is concerned that her daughter might have been abused…
Reassure the mother that this is normal behavior
- Normal sexual behavior in toddlers:
- Exploring one’s own genitals or other’s genitals
- Masturbatory movements
- Undressing self or others
- Abnormal sexual behavior in toddlers (concerning for abuse):
- Repeated insertion of objects into vagina/anus
- Age-inappropriate sexual knowledge
- Sex play involving genital contact
- Use of coercive behavior in sex play
- Key idea: Being hesitant about leaving mother, intermittent nighttime awakening and not wanting to share toys are normal behaviors for a toddler, especially in setting of no behavior problems
2) A 6-year-old boy is brought to the emergency department 10 minutes after a firecracker accident; he has pain…
Loss of corneal epithelium
- Key idea: Patients with corneal abrasion often present with pain, tearing and foreign body sensation and next best step would likely be visualization after Flourescein staining
- Obstruction of lacrimal duct –> Nasolacrimal duct obstruction –> Unilateral, painless tearing
- Retinal detachment –> Patient with severe myopia and/or trauma presenting with floaters and lights followed by painless loss of vision “like a curtain being dropped down”
- Increased intra-ocular pressure –> Glaucoma –> Painless loss of peripheral vision
3) An 8-year-old boy is brought to the physician because of a 4-day history of pallor. He has not had cough, rash…
Meckel scan
- Young boy with bloody stools c/b anemia with an otherwise normal exam most concerning for a Meckel diverticulum (most common cause of GI bleed in a child) –> Work-up with technetium 99m pertechnetate scan, which is taken up by gastric mucosa and therefore should only light up the stomach in somebody without a Meckel diverticulum
- Key idea: Meckel diverticulum can be remembered by Rule of 2’s: 2X more common in boys, 2 inches long, 2 feet from ileocecal valve, 2% of population, contains 2 types of ectopic tissue (pancreatic and gastric)
- Anoscopy –> Hemorrhoids –> More commonly seen in adults and rarely leads to sufficient bleeding to produce anemia
4) An otherwise healthy 6-year-old boy is brought to the physician because of the growth of pubic hair over the past 2 years…
Adrenal cortex
- Key idea: 2 main sources of testosterone are the testes and the adrenal cortex (zona fasciculata) and given that this patient has age-appropriate testicular size we are more concerned for androgens coming from the adrenal cortex
- Key idea: Precocious puberty defined by secondary sexual development in girls younger than 8 years old and in boys younger than 9 years old
- Key idea: First step in setting of suspected precocious puberty is assessment of bone age of child followed by an LH level, with advanced bone age + high LH –> Central precocious puberty (increased LH/FSH stimulates testicular production of androgens) and advanced bone age + low LH –> Peripheral precocious puberty (increased androgen production by adrenals –> Decreased LH/FSH by negative feedback –> Normal sized testes)
5) A 20-year-old woman, gravida 1, para 0, at 36 weeks’ gestation delivers a stillborn infant. She had no prenatal care, and the…
Abnormality in Type 1 collagen
- Key idea: Blue sclerae is virtually pathognomonic for osteogenesis imperfecta
- Features of osteogenesis imperfecta
- Frequent fractures
- Blue sclerae (due to visualization of underlying choroidal veins in eye)
- Conductive hearing loss (due to abnormal bone formation in middle ear)
- Dentigenesis imperfecta
- Short-normal stature
- Joint hypermobility
- Fetal alcohol syndrome –> Behavioral problems, small head and body, facial abnormalities (thin upper lip, smooth philtrum, etc.)
- Phenytoin –> Fetal hydantoin syndrome (facial problems, limb problems, etc.)
- Cocaine use –> Placental abruption, small fetus/baby
6) A 10-year-old boy with sickle cell disease is brought to the physician because of a 2-day history of increasing fatigue and shortness…
Cardiac output
- Young boy with sickle cell disease who presents with persistent infection + hypotension + fever and anemia, most concerning for dual diagnoses of sepsis and anemia –> Each can individually lead to increased cardiac output (as supported by the patient’s active precordium)
- Key idea: Anemia = Decreased RBC mass –> Decreased O2 carrying capacity of blood –> Compensatory increase in cardiac output to enable adequate oxygen delivery to tissues (chronic anemia can lead to high-output heart failure)
- Key idea: Sepsis –> Bacterial endotoxins lead to arteriolar vasodilation –> Decreased systemic vascular resistance (afterload) –> Heart is pumping against less resistance –> Increased cardiac output
- Key idea: Distributive shock (septic, anaphylactic or neurogenic) is the only category of shock that leads to decreased SVR and increased CO
- Increased pulmonary vascular resistance –> Pulmonary hypertension (genetic, cor pulmonale, secondary to left-sided heart failure, etc.)
7) A 5-year-old boy is brought to the physician for a well-child examination. He is active and has been healthy except…
Thalassemia minor
- Young boy of Southeast Asian descent and unremarkable history found to have microcytic anemia with decreased red cell distribution width and target cells on smear most concerning for thalassemia minor
- Key idea: Red cell distribution width basically looks at the range of RBC sizes and will be decreased in thalassemia (where all the RBCs are small) and will be increased in iron deficiency anemia (where some RBCs get enough iron and are normal sized and some don’t get enough and are small)
- Microcytic anemia differential:
- Iron deficiency anemia
- Thalassemia
- Lead poisoning
- Sideroblastic anemia (genetic, alcohol abuse, etc.)
- Patients with African descent with alpha thalassemia minor tend to have trans variant (one alpha gene missing from each chromosome 16), whereas patients with Asian descent tend to have cis variant (both alpha genes missing from same chromosome 16)
- Note: I remember that there are two genes for beta-globin and therefore it must be on chromosome 11 (1+1), whereas there are four genes for alpha-globin and therefore it must be on chromosome 16 (2^4)
- Bone marrow suppression –> Low RBCs, WBCs and platelets
8) A 2-week-old female newborn is brought to the physician because of bruising on her arms and legs for 2 days. She was born…
Hemangioma
- Infant with a large hemangioma of the thigh who presents with purpura and petechiae concerning for thrombocytopenia which is confirmed by a low platelet count, most consistent with Kasabach-Merritt syndrome (large or rapidly growing vascular lesion –> platelet trapping (low platelet count) and consumption of fibrinogen/clotting factors (consumptive coagulopathy)
- Cystic hygroma –> Swelling/mass on the back of the neck due to abnormal lymphatic development; often associated with Turner syndrome
- Neurofibromatosis type 1 –> Neurofibromas, Lisch nodules (pigmented hamartomas in eye), optic glioma, cafe-au-lait spots, pheochromocytoma, seizures/brain tumors
9) A previously healthy 1-month-old girl is brought to the emergency department because of a 3-day history of cough and difficulty…
Pertussis
- Key idea: B. pertussis classically leads to long/severe bouts of coughing followed by an inspiratory “whoop”
- Key idea: In addition to an inspiratory whoop, B. pertussis is known to lead to exceedingly forceful coughing which can lead to:
- Post-tussive vomiting
- Facial petechiae
- Subconjunctival hemorrhage
- Key idea: B. pertussis is unique in that it is a bacterial infection but rather than a neutrophilic-predominant leukocytosis it leads to a lymphocyte-predominant leukocytosis due to pertussis toxin (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5761200/)
- Key idea: B. pertussis is treated with a macrolide (classically azithromycin)
- Acute bronchiolitis –> Wheezing
- Viral laryngotracheobronchitis (Croup) –> Stridor
- Foreign body aspiration –> Sudden bout of coughing followed by asymmetric wheezing with asymmetric lung expansion on chest x-ray
- Chlamydial pneumonia –> ~6-8 weeks post-birth with Staccato cough + Eosinophilia
10) A 2-year-old girl is brought to the emergency department 30 minutes after a syncopal episode. At the time of the episode…
Breath holding
- Key idea: Breath holding spells can be seen in children 6 months to 2 years of age predominantly, with the two major types being:
- Cyanotic breath-holding spells –> Crying/trauma associated with breath-holding, cyanosis and loss of consciousness
- Pallid breath-holding spells –> Crying/trauma associated with breath-holding, pallor and loss of consciousness
- Key idea: Atonic seizure leads to loss of muscle tone with NO loss of consciousness or unresponsiveness
- Key idea: Because the patient was normal immediately after event with no post-ictal state, that virtually rules out complex partial seizures
- Low cardiac output –> Syncope –> Vasovagal, hypovolemia, heart defect, PE, etc.
11) A previously healthy 6-month-old boy is admitted to the hospital because of a 1-day history of fever, lethargy and vomiting…
Increased secretion of ADH (vasopressin)
- Infant with signs of meningitis (fever, nuchal rigidity, etc.) also found to have hyponatremia most likely due to SIADH caused by CNS pathology
- Common causes of SIADH:
- Medications (antidepressants, anticonvulsants, cyclophosphamide, etc.)
- Paraneoplastic phenomenon (small cell lung cancer, renal cell carcinoma)
- CNS pathology (tumor, brain trauma, etc.)
- Lung pathology (pneumonia, COPD exacerbation, etc.)
- Note: Another pathway from meningitis to hyponatremia that would not present as acutely could be Meningococcal meningitis –> Waterhouse-Friderichsen syndrome –> Adrenal insufficiency –> Hyponatremia
12) A 10-month-old girl is brought to the physician because of a 5-day history of a rash over the cheeks and diaper area that…
Atopic dermatitis
- Key idea: While we typically think of atopic dermatitis occurring in flexural regions of the extremities (cubital fossa, popliteal fossa), atopic dermatitis is a heterogenous disease especially in infants where it is commonly seen on the face and in the inguinal area (moist, irritated area)
- Candidiasis –> Diaper rash with satellite regions
13) A 1-day-old, 1400-g (3-lb 2-oz) newborn has tachypnea, expiratory grunting, flaring of the alae nasi, and peripheral edema…
Respiratory and metabolic acidosis
- Key idea: Patient with an acidosis based on ABG found to have a low HCO3 and an increased PCO2 most consistent with a mixed respiratory and metabolic acidosis
- Although in this case the patient’s metabolic acidosis in this case clearly does not have respiratory compensation, it can be formally evaluated with the Winter’s formula which uses the patient’s HCO3- (degree of metabolic acidosis) to estimate what normal respiratory compensation should be:
- Compensated PCO2 = (HCO3 x 1.5) + 8 +/-2 = (14 * 1.5) + 8 +/- 2 = [27, 31] –> In this case the PCO2 is higher than upper limit of the range (50 > 31), and therefore we know there is a concomitant respiratory acidosis
- Just for fun: Anion gap = [Na+] – (HCO3 + Cl) = 138 – (14 + 100) = 24 > 12 –> Anion-gap metabolic acidosis
- Good article for approach to acid-base abnormalities: https://www.nejm.org/doi/pdf/10.1056/NEJMra1003327
14) A 3-year-old boy is brought to the emergency department because of a 1-day history of increasingly severe abdominal pain…
CT scan of the abdomen
- Young patient with blunt abdominal trauma found to have severe epigastric discomfort + epigastric mass most consistent with a duodenal hematoma –> Work-up with abdominal CT
- Key idea: Amylase and lipase are NOT specific to pancreatitis and can be seen generally in setting of blunt abdominal trauma
- Air enema –> Intussusception –> Toddler with episodic abdominal pain +/- bloody stools with decreased pain when drawing the knees to the chest
- Barium enema –> Hirschsprung’s disease vs Meconium ileus
- Key idea: Abdominal x-ray useful in setting of small bowel obstruction but not in setting of duodenal hematoma
15) A 9-year-old boy with chronic renal failure is brought to the physician for a follow-up examination 2 days after he began enalapril…
Suppression of aldosterone
- Key idea: Enalapril –> ACE inhibitor –> Decreased Angiotensin II –> Decreased aldosterone –> Decreased Na+ reabsorption in exchange for K+/ H+ secretion into the collecting duct –> Hyperkalemia and Metabolic acidosis
- In a patient with renal artery stenosis, ACE inhibitors can lead to decreased glomerular perfusion (which would be reflected by increased creatinine/BUN) –> INCREASED RAAS activity –> Increased aldosterone –> Increased Na+ reabsorption in exchange for K+/H+ secretion –> Hypokalemia and metabolic alkalosis
16) A previously healthy 8-year-old girl is brought to the emergency department because of fever, rash, and lethargy for 4 hours…
Complement system immunodeficiency
- Young girl with a family history of severe meningococcemia who presents with signs of meningococcemia (meningitis (fever, nuchal rigidity) + Purpuric skin lesions) most concerning for a complement deficiency which predisposed to recurrent Neisseria infections (gonorrhea, meningococcus)
- AIDS –> Recurrent viral/fungal/mycobacterial infections + Failure to thrive
- Congenital humoral system immunodeficiency –> B cell deficiency –> Recurrent sinopulmonary and mucosal infections (due to loss of IgA) primarily due to encapsulated bacteria (due to loss of IgA) and parasites such as Giardia (due to loss of IgE)
17) A 15-year-old girl is brought to the physician because of a 3-day history of severe pain and swelling in her right sternoclavicular joint…
Culture of the aspirate fluid
- Adolescent girl with fever + swelling of the sternoclavicular joint with aspiration showing thick purulent fluid with gram-negative diplococci on gram stain most consistent with gonococcal arthritis –> Culture of N. gonorrhoeae is of tremendous importance both for definite diagnosis and for determination of drug susceptibility although most can be treated with Ceftriaxone + Azithromycin/Doxycycline
- Key idea: Gonorrhea is the most common cause of septic arthritis in adolescents/young adults and can lead to a sexually-transmitted cervicitis, urethritis or pharyngitis that can then disseminate hematogenously
- Key idea: Disseminated gonococcal infection classically leads to Purulent monoarthritis OR Triad of tenosynovitis + pustular dermatitis + migratory polyarthritis
18) A 5000-g (11-lb 1-oz) male infant is born at term to a 35-year-old woman following an uncomplicated pregnancy and delivery…
Hypoglycemia
- Key idea: Constellation of macrosomia + macroglossia + omphalocele/umbilical hernia most consistent with Beckwith-Wiedemann syndrome which can also lead to hypoglycemia + malignancies
- Key idea: Patients with Beckwith-Wiedemann syndrome should be followed with serial abdominal ultrasound (looking for Wilms tumor) and alpha-fetoprotein measurement (looking for hepatoblastoma)
- Key idea: Most common cause of macrosomia is Gestational diabetes, which would also put patient at increased risk of hypoglycemia because glucose can cross the placenta but insulin CANNOT, and therefore when pregnant woman have gestational diabetes the baby will develop islet cell hypertrophy in response to the high levels of glucose they are receiving in utero –> Therefore, newborns of mothers with gestational diabetes are at risk for hypoglycemia because their pancreas will continue to produce large amounts of insulin but they are NO LONGER receiving high levels of glucose from the mother, leading to excessive insulin pushing them to be hypoglycemic
- Imperforate anus –> Failure to pass meconium
- Renal tubular acidosis –> Non-Anion gap metabolic acidosis
19) A previously healthy 1-year-old boy is brought to the physician because of a 2-month history of increasing weakness and difficulty feeding…
Progressive infantile spinal muscular atrophy
- Infant with chronic weakness with signs of a lower motor neuron defect (fasciculations, hypotonia) most consistent with spinal muscular atrophy
- Botulism –> ACUTE descending weakness after eating honey or being exposed to dust or construction site
- Guillain-Barre –> Patient with viral or GI illness followed by an ACUTE ASCENDING weakness often with sensory symptoms
- Myasthenia gravis –> Oculobulbar weakness worse at the end of the day often seen in young women and old men
- Transverse myelitis –> Spinal lesion leading to unilateral sensory and UMN signs below a certain spinal level
20) A female newborn has mild cyanosis and a cardiac murmur 4 hours after an uncomplicated vaginal delivery. Heart sounds are heard…
Sepsis
- Key idea: Asplenia –> Increased risk of infection by encapsulated bacteria (SHiN –> Strep pneumo, H influenzae, Neisseria) because the spleen often removes opsonized bacteria and encapsulated bugs require opsonization for adequate clearance
- Key idea: Howell-Jolly bodies are a sign of functional asplenia because RBCs with Howell-Jolly bodies are typically cleared by the spleen
- Related idea: Patients with sickle cell disease have functional asplenia due to thrombotic damage to the spleen and are therefore treated with daily penicillin until 5 years of age to reduce the risk of sepsis (primarily due to Strep pneumo)
21) A previously healthy 16-year-old girl is brought to the physician because of a 4-month history of progressive fatigue and nervousness…
TSH receptor autoantibodies
- Adolescent girl with signs of hyperthyroidism (weight loss despite increased appetite, nervousness, tremor) found to have exophthalmos and a diffusely enlarged thyroid gland most concerning for Graves disease
- Key idea: All causes of hyperthyroidism can lead to lid lag, but exophthalmos is quite specific for Graves disease (because the autoantibodies stimulate fibroblasts behind the eye –> Expansion of retro-orbital tissues)
- Levothyroxine overdose –> Would NOT lead to enlarged thyroid gland
- Lymphocytic infiltration of thyroid gland –> Hashimoto thyroiditis –> Although can lead to a transient hyperthyroid state (due to release of pre-formed thyroid hormone from the damaged thyroid gland), it would NOT persist for months
22) A 17-year-old girl comes to the physician for a routine health maintenance examination prior to beginning college…
Type 2 diabetes mellitus
- Adolescent obese girl with signs of hyperandrogenism (hirsutism [hair growth in androgen-sensitive areas], acne) and menstrual irregularity most concerning for PCOS
- Key idea: While insulin resistance is NOT part of the formal diagnostic criteria for PCOS, it is often a component of PCOS and should be increasingly suspected in this patient given her history of polyuria + Acanthosis nigricans (hyperpigmented plaques on neck and axillae) which are concerning for full-blown Type 2 diabetes
- Diagnosis of PCOS requires at least 2 of the 3 following criteria:
- Irregular menses (anovulation)
- Polycystic ovaries on ultrasound
- Clinical (acne, hirsutism) or laboratory (elevated testosterone) signs of hyperandrogenism
- Cushing syndrome –> Weight gain, central obesity, buffalo hump, hypertension, etc.
23) An 18-month-old boy has had cough, coryza, vomiting, and diarrhea for 5 days and pallor and lethargy for 1 day. His mother states…
Hemolytic-uremic syndrome
- Toddler with history of acute diarrhea who now presents with pallor with anemia, lethargy, thrombocytopenia, and an AKI with dark urine most concerning for Hemolytic-uremic syndrome
- Mnemonic to remember the signs/symptoms of thrombotic thrombocytopenia purpura (TTP ) and hemolytic uremic syndrome (HUS) is Brain FART: Brain (neuro) symptoms, Fever, hemolytic Anemia, Renal disease and Thrombocytopenia
- Schistocytes = Macroangiopathic hemolytic anemia (mechanical heart valve, aortic steonsis) or Microangiopathic hemolytic anemia (DIC, TTP, HUS, SLE, HELLP syndrome, hypertensive emergency)
- Goodpasture syndrome –> Young adult with hemoptysis and hematuria
- Henoch-Schonlein purpura –> Palpable purpura on buttocks, arthralgias, GI pain with increased risk of intussusception
- PSGN –> Often seen weeks after strep pharyngitis
24) A previously healthy 7-year-old girl is admitted to the hospital because of an 11-day history of fever, fatigue, and progressive nonproductive…
Histoplasmosis
- Young girl with contact with bird feces who presents with fever, cough and non-specific symptoms (fatigue, weight loss) found to have a lymphocytic leukocytosis, negative TB test and imaging demonstrating hilar lymphadenopathy + abundant pulmonary nodules found to have necrotizing granulomas on biopsy most consistent with histoplasmosis
- Key idea: While histoplasmosis is most classically associated with exposure to caves in the Midwest, the reason that caves are an important risk factors is because of bird/bat droppings found within these caves that are then inhaled
- ALL –> Significant leukocytosis + Anemia + Thrombocytopenia + Bone pain
- Q fever –> Exposure to farm animals (often vets, farmers) who develop acute fever, cough and hepatitis with granulomas, but imaging would appear more consolidative with a lobar pneumonia-like picture
25) A 2807-g (6-lb 3-oz) newborn has a strong cry immediately after delivery. She was born at term following an uncomplicated…
Tactile stimulation and oxygen therapy
- Key idea: For most normal newborns, the primary concerns at delivery are maintaining warmth (by keeping room warm and drying) and tactile stimulation (often through process of drying) because these stimulate respirations in the newborn
- PPV via mask and intubation are more invasive and not yet necessary in this infant who is NOT showing signs of significant respiratory distress
26) A previously healthy 6-year-old boy is brought to the physician because of progressive hair loss over the past 4…
Oral antifungals
- Key idea: Patient most likely has a kerion, which is an abscess caused by a fungal infection most commonly on the scalp secondary to tinea capitis
- Key idea: Tinea capitis is more commonly seen in African-American children and importantly is treated with oral antifungals (Griseofulvin PO, Terbinafine PO, etc.)
27) A 17-year-old girl comes to the physician because of a 2-day history of pain in the right lower quadrant of her abdomen…
Observation
- Adolescent girl with a functional ovarian cyst (symptomatic ovarian cyst with worsening symptoms seen with menses) –> Often managed with OCPs (to reduce pain associated with menses) and/or follow-up examination in 6 weeks (many cysts go away in 1-2 menstrual cycles)
- Ultrasound findings of ovarian pathology:
- Ovarian cyst: Cystic mass +/- free fluid in pelvis if ruptured
- Serous ovarian cancer: Complex masses with solid components
- Theca-lutein cyst: Large, bilateral cystic masses
- Tubo-ovarian abscess: Multiloculated cystic masses with distortion of normal adnexal structures
- Diagnostic laparoscopy –> Ruptured ectopic pregnancy, endometriosis, adhesions
28) A 12-year-old girl is brought to the physician for a well-child examination. She has no history of serious illness. Immunizations…
Within the next year
- Key idea: Both boys and girls should ideally receive the HPV vaccine around age 11-12 because it can help these individuals avoid HPV infection once they become sexually active
- Note: HPV vaccine can be administered up to age 26 (although recent push for this age limit to be extended), but ideally should be given at 11-12 years of age
- First pap smear –> 21 years of age
29) A 3-week-old boy is brought to the physician 4 hours after the onset of vomiting watery, green material. His mother says that he…
Volvulus
- Infant with acute onset of abdominal pain and bilious vomiting found to have signs of small bowel obstruction on imaging (dilated loops of bowel + air-fluid levels) most concerning for malrotation with volvulus
- General causes of bilious emesis in a neonate:
- Atresias: Duodenal (down syndrome), jejunal (maternal cocaine use)
- Failure to pass meconium: Meconium ileus (cystic fibrosis, inspissated stool), Hirschsprung disease (down syndrome, squirt sign), Imperforate anus
- Structural problems: Incarcerated hernia, malrotation with volvulus, necrotizing enterocolitis
- Key idea: Of the diagnoses listed above, malrotation and incarcerated hernia are the main ones that could present days-weeks AFTER birth
- Key idea: Although intussusception is most classically associated with pain being relieved by drawing knees to chest, that would more classically occur in a 2-5 year old child and leads to recurrent episodes of abdominal pain +/- bloody bowel movements
- Pyloric stenosis –> Projectile, non-bilious vomiting (obstruction proximal to duodenum) often seen around 6 weeks of life
30) A 7-month-old girl is brought to the physician because of a 3-day history of fever and cough. She was born at term…
HIV infection
- Infant HIV –> Recurrent viral/fungal/mycobacterial infections + Chronic diarrhea + Failure to thrive
- Key idea: Thrush (white plaques on buccal mucosa) and Pneumocystis pneumonia –> Sign of T cell deficiency –> HIV, SCID, DiGeorge syndrome, etc.
- Chronic granulomatous disease –> Young boy (X-linked) with recurrent skin+pulmonary infections with Catalase positive organisms (SPANS BELCH: Staph aureus, Pseudomonas, Aspergillus, Nocardia, Serratia, Burkholderia cepacea, E coli, Listeria, Candida, H pylori)
- Complement deficiency –> Recurrent Neisseria infection
- SCID –> Recurrent infections with all types of organisms + Failure to thrive + Absent thymus + Absent/scanty lymph nodes and tonsillar tissue
- Wiskott-Aldrich –> WATER –> Wiskott Aldrich Thrombocytopenia Eczema Recurrent infections
- Bruton’s agammaglobulinemia –> B cell dysfunction –> Young boy (X-linked) with recurrent sinopulmonary and mucosal infections with encapsulated bacteria and parasites
- DiGeorge –> CATCH-22 –> Cardiac abnormalities, Abnormal facies, Thymic aplasia, Cleft lip/palate, Hypocalcemia (loss of parathyroid glands)
31) A previously healthy 16-year-old girl is brought to the physician by her parents 1 day after she fainted during soccer practice…
ECG
- Adolescent girl with family history of sudden death who presents following a syncopal episode while exercising most concerning for hypertrophic obstructive cardiomyopathy (HOCM) or some form of arrhythmia (long QT syndrome, etc.) –> Should work-up initially with an ECG which could investigate both of these causes
- Key idea: SYNCOPE WITH EXERTION IS VERY CONCERNING (often points to structural heart problem and/or arrhythmias) AND SHOULD ALWAYS BE WORKED-UP!!!
32) A 2-month-old boy is brought to the physician because of a 2-week history of sweating and fatigue during feedings. His mother…
Left-to-right shunt
- Infant with sweating while eating and tachypnea/tachycardia at rest found to have a palpable parasternal lift and a blowing holosystolic murmur at the lower left sternal border most consistent with a Ventricular septal defect (most common congenital heart defect)
- Key idea: Babies cannot move around and therefore their main form of exertion is when they are eating!
- Key idea: The right ventricle is the most anterior portion of the heart and therefore a parasternal heave is most often indicative of increased RV pressures/hypertrophy
- Key idea: If left-to-right shunt left untreated, over the span of years it can reverse to be a right-to-left shunt due to increased pulmonary vascular resistance making right-to-left shunt more favorable (Eisenmenger syndrome)
- Key idea: Right-to-left shunt would lead to early cyanosis with these causes remembered with the 5 T’s
- 1 T: Truncus arteriosus
- 2 T: Transposition of the great vessels
- 3 T: Tricuspid atresia
- 4 T: Tetralogy of Fallot
- 5 T: Total anomalous pulmonary venous return
33) A 9-year-old boy is admitted to the hospital for treatment of status asthmaticus. He is intubated and mechanically ventilated…
Alveolar collapse
- Young patient with malpositioned tube in the right mainstem bronchus –> Absorption atelectasis of the right upper lobe of the lung (haziness in the right upper lobe)
- Key idea: Right mainstem bronchus most likely to have a malpositioned tube for the same reason why it is most likely site of aspiration event (right mainstem bronchus is most vertical, widest, and shortest)
- Key idea: An intubated patient with asymmetric chest expansion and/or asymmetric breath sounds often a sign of right mainstem bronchus intubation, which will NOT have hypotension or vital sign derangements like a tension pneumothorax
- Bronchial dilation –> Bronchiectasis –> Seen in setting of recurrent infections leading to chronic productive cough
34) A 2-month-old boy is brought to the physician for a well-child examination. Pregnancy was uncomplicated. He was born at term…
Sternomastoid injury
- Infant with head deviated to the right + Flattening of posterior right head + Mass in left neck most consistent with congenital muscular torticollis (sternocleidomastoid muscle is tight/contracted)
- Key idea: Birth trauma or malpositioned head in utero –> Damage to sternocleidomastoid muscle –> Fibrosis
- Clavicle fracture –> Often seen immediately/soon after a difficult delivery leading to crepitus of the clavicle + pain with movement of arm
35) A previously healthy 10-year-old boy is brought to the emergency department 1 hour after falling against the crossbar…
Retrograde urethrography
- Young patient with straddle injury presenting with perineal hematoma and blood at urethral meatus concerning for an injury to the bulbar (spongy) urethra
- Key idea: Retrograde urethrogram indicated in pateints with suspected urethral injury, with pelvic fracture often leading to membranous urethra damage and perineal straddle injury leading to bulbar (spongy) urethra damage –> In either case, presentation is often penile trauma +/- Blood at urethral meatus +/- hematuria +/- difficulty voiding
- Key idea: Insertion of a catheter is CONTRAINDICATED in setting of suspected urethral injury
- IV pyelography –> Sometimes indicated in setting of blunt genitourinary trauma (CVA pain + Hematuria following a traumatic event [often to the back])
36) A female newborn is found to have mild cyanosis periorally and of the hands and feet 4 hours after birth. She was born at…
Acrocyanosis
- Peripheral cyanosis (hands and feet) is present in most healthy newborns (including this infant with APGAR scores of 9)
- In contrast, central cyanosis (trunk and/or mucous membranes) is NEVER normal (and would be seen in Tetralogy of Fallot and methemoglobinemia)
- Addison disease –> Primary adrenal insufficiency –> Hyponatremia, hyperkalemia, hyperpigmentation, hypoglycemia, hypotension
37) An asymptomatic 10-year-old boy is brought to the physician for a well-child examination. He has no history of serious illness…
Excessive intake of total calories
- Active child who eats a healthy diet but drinks multiple glasses of milk and juice per day presenting with increased weight most likely due to increased calorie intake
- Key idea: If Calories in > Calories out –> Weight gain
- Key idea: Children are overweight if their BMI is greater than the 85th percentile and are obese if their BMI is greater than the 95th percentile
38) Four days after admission to the hospital for evaluation of a high-grade fever, a 12-year-old girl has decreased urine output…
Intravenous administration of calcium chloride
- Young girl with subacute history of fever + facial rash + diffuse joint pain + Glomerulonephritis (most consistent with systemic lupus erythematosus) found to have a potassium level of 9 with ECG changes (peaked T changes) who should first receive calcium carbonate to stabilize the cardiac membrane
- Indications for calcium carbonate in setting of hyperkalemia:
- ECG changes
- Potassium > 7.0
- Rapidly rising potassium due to tissue breakdown
- Management of hyperkalemia
- Immediate: IV calcium to stabilize cardiac membrane
- Quickly: Shift potassium into cells by giving:
- Insulin + Glucose (Insulin –> K+ shift into cells)
- Albuterol inhaler (Beta-2 agonist –> Stimulates Na/K ATPase –> K+ shift into cells)
- Sodium bicarbonate (alkalosis –> K+ shift into cells)
- Decrease total K+:
- Diuretics
- Hemodialysis (AEIOU)
- Cation exchange resins (sodium polystyrene sulfonate)
39) A 6-year-old girl with nephrotic syndrome is brought to the physician because of a 2-day history of fever, abdominal swelling…
Spontaneous bacterial peritonitis
- Young girl with nephrotic syndrome (protein loss) found to have abdominal distention + diffuse abdominal tenderness + fever most concerning for spontaneous bacterial peritonitis
- Key idea: Spontaneous bacterial peritonitis formally diagnosed by ascitic fluid with PMN concentration of 250 or higher
- Causes of Ascites:
- Increased hydrostatic pressure
- Portal hypertension in setting of cirrhosis
- Increased venous pressure due to HF exacerbation
- Decreased oncotic pressure
- Nephrotic syndrome
- Malnutrition/Low protein diet
- Increased hydrostatic pressure
- Celiac disease –> Fat malabsorption + dermatitis herpetiformis + Iron deficiency anemia (duodenal absorption impaired –> no iron absorption in duodenum)
- IBD –> Chronic history of abdominal pain + bloody stools + systemic findings
- Necrotizing enterocolitis and Hirschsprung would more commonly be seen/discovered in infancy
- Intussusception –> Toddler with recurrent episodes of abdominal pain + bloody stools that improves when knees are drawn to the chest
40) A 25-year-old woman, gravida 2, para 1, at 20 weeks’ gestation comes to the physician for a routine prenatal visit. She feels well…
Exclusively breast-feed for at least 6 months
- Generally, infants should receive exclusive breastfeeding until 6 months of age, at which point they should receive pureed foods and then at 1 year can start having cow’s milk
- Note: Exclusively breastfed infants require supplementation with Iron and Vitamin D
41) A 7-year-old Hispanic girl with a 1-year history of acute lymphocytic leukemia is brought to the physician for a routine examination…
Advise them to continue her medications while investigating the information further
- Key idea: Herbal remedies can sometimes be integrated into treatment plans if they don’t interact with other medications, but they should NOT take the place of evidence-based medications (especially when managing deadly diseases such as leukemia)
- Not appropriate to drop patient for asking a question and dismissing patient outright could fracture patient-physician relationship
42) A 2-week-old girl is brought for her first well-child examination. Newborn screening showed an increased thyroid-stimulating hormone (TSH)…
Measurement of serum thyroxine (T4) and TSH concentrations
- Newborn born to a mother on anti-thyroid therapy has a benign exam but an elevated TSH, which may reflect true hypothyroidism or may reflect the fact that some anti-thyroid therapy crossed the placenta and suppressed thyroid hormone production in utero –> Next best step would be repeat thyroid studies after giving infant several weeks to re-establish thyroid function if it is due to placental transmission of anti-thyroid medication
- Key idea: Hypothyroidism can negatively impact infant development, and in particular can lead to non-reversible changes in cognition/intelligence, and can be treated pretty easily, so reassurance would NOT be appropriate in this case
43) A previously healthy 16-year-old girl is brought to the emergency department by friends after they found her unresponsive at a party…
Naloxone
- Altered mental status + Respiratory depression + Pinpoint pupils + Decreased GI activity = Opioid intoxication –> Treated emergently with naloxone (opioid receptor blocker)
- 0.9% normal saline often useful in setting of hypotension due to distributive, hypovolemic or cardiogenic shock
44) A 4-month-old female infant is brought to the physician by her mother for a routine examination. The patient was born at 27 weeks’ gestation…
Pulmonary hypertension
- Infant born prematurely who has required chronic oxygen therapy with abnormal pulmonary exam and signs of pulmonary hypertension (Loud S2 + Precordial Heave + Right axis deviation) most consistent with bronchopulmonary dysplasia complicated by pulmonary hypertension
- Key idea: Loud S2 + Precordial heave = Pulmonary hypertension
- Key idea: Oxygen can actually lead to production of free radicals and therefore infants with chronic O2 requirements can have diseases related to excess O2, most prominently bronchopulmonary dysplasia and retinopathy of prematurity (reason why Stevie Wonder is blind!)
- Key idea: Obstructive lung disease is a known cause of pulmonary hypertension (cor pulmonale) and the reason is that the lung vasculature, in contrast to vasculature supplying the other tissues in our bodies, will constrict in the setting of hypoxia to divert blood to areas of the lung that are more well-oxygenated –> The problem in COPD, bronchopulmonary dysplasia and other obstructive lung diseases is that the entire lung has poor O2 tension such that there will be diffuse vasoconstriction –> increased pulmonary vascular resistance –> Pulmonary hypertension
45) A 7-year-old boy is brought to the emergency department 30 minutes after the onset of confusion, decreased awareness…
Oxygen
- Young boy was found next to a space heater with altered mental status + headache + dyspnea most concerning for carbon monoxide poisoning –> Treated with 100% hyperbaric oxygen to enable O2 to displace carbon monoxide from hemoglobin
- Key idea: Carbon monoxide poisoning classically leads to cherry-red skin + headache + altered mental status
- Methemoglobinemia –> Methylene blue + Vitamin C
- Iron poisoning –> Deferoxime
- Organophosphate poisoning –> Atropine + Pralidoxime
- Tylenol poisoning –> Acetylcysteine
- Arsenic poisoning –> Dimercaprol
46) A previously healthy 14-year-old girl is brought to the physician because of a 6-week history of right knee pain…
Patellofemoral instability
- Patellofemoral syndrome is a common cause of knee pain in adolescent girls and classically lead to pain in the anterior knee worse with climbing stairs, squatting or quadriceps exercises –> Treatment is with quadriceps strengthening and activity modification
- Legg-Calve-Perthes –> Idiopathic avascular necrosis of the hip in a child ~5-7 years old
- Septic arthritis –> Fever + joint pain + warm joint –> TAP THE KNEE!
- Transient synovitis –> Often seen following a viral illness
47) A 15-year-old girl is brought to the emergency department 2 hours after she attempted suicide by taking an overdose…
Na: 141 // K: 4.2 // Cl: 102 // HCO3: 8
- Key idea: Aspirin overdose leads to an early respiratory alkalosis followed by an anion-gap metabolic acidosis, with the above option being the only one demonstrating an anion-gap metabolic acidosis
- Anion-gap = Na – (Cl + HCO3) = 141 – (102 + 8) = 31 > 12 –> Anion-gap metabolic acidosis
- Key idea: Aspirin poisoning treated with sodium bicarbonate (alkalinizes urine) +/- hemodialysis
48) A previously healthy 16-year-old girl comes to the physician because of heavy vaginal bleeding for 5 weeks. Menarche was at the age…
Anovulation
- Key idea: Progesterone levels should be elevated in the luteal phase of the menstrual cycle (after ovulation has taken place and the corpus luteum has been formed), but we see a low progesterone in this patient tells us that ovulation did not occur
- Key idea: Normal for adolescents to have anovulation due to an immature HPG axis
- Note: Von Willebrand disease is a common cause of heavy menstrual bleeding but would not explain the menstrual irregularities or abnormal progesterone levels
- Turner syndrome –> Primary amenorrhea (absence of menstrual periods)
- Pituitary tumor –> Hormone problems + Bitemporal hemianopsia + Headache
49) A full-term 24-hour newborn has respiratory distress and seizures. Apgar scores were 8 and 9 at 1 and 5 minutes…
Group B streptococcal sepsis
- Newborn with respiratory distress + seizures + leukocytosis + abnormal chest x-ray + normal lumbar puncture most consistent with pneumonia c/b sepsis
- Key idea: Early-onset sepsis often due to Group B Strep, E. Coli and Listeria acquired during passage of baby through birth canal
- Meconium aspiration –> Respiratory distress but likely no seizures
- Pneumococcal meningitis –> Low glucose and High WBCs with neutrophilic predominance on lumbar puncture
50) A 9-year-old girl is brought to the physician because of headache and dizziness for the past week. She has a history of recurrent urinary…
Measurement of serum urea nitrogen and creatinine concentrations
- Young girl with history of recurrent urinary tract infections and pyelonephritis due to vesicoureteral reflux who presents with hypertension and signs of chronic hypertension (narrowing of retinal arteries) concerning for signs of chronic kidney disease complicated by hypertensive urgency which should be worked up with BUN/creatinine measurements
- Key idea: Damage to kidney leads to impaired salt excretion –> Increased total Na+ levels –> Increased total body water –> Chronic hypertension
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