NBME Medicine Form 6 - Answers & Explanations
Updated: Mar 22
Author: Sagie Haziza & Gennadiy Guralnik
Editor: Jordan Abrams
1) Abnormal red blood cell membrane
• Hereditary spherocytosis: jaundice, anemia, high-normal MHCH, loss of central pallor
• ⊖ Direct Coombs rules out AIHA
• Cholecystectomy → chronic hemolysis → indirect bilirubin gallstones
2) Positive findings for anti-centromere antibody
• CREST syndrome: calcinosis cutis, Raynaud phenomenon, esophageal dysmotility,
sclerodactyly, telangiectasia
3) Syringomyelia
• Cystic cavity in spinal cord → block of anterior white commissure (spinothalamic tract) →
bilateral, cape-like loss of pain and temperature
• Fine touch sensation preserved
• Associated with Chiari 1 malformation
4) Ruptured papillary muscle
• Acute, usually within 3-5 days post MI
• Typically with RCA infarction (posteromedial papillary muscle)
• Clinical findings: Severe pulmonary edema, new holosystolic murmur
5) No further testing is indicated
• Normal BP (140/90)
• Hematocrit normal (42%)
• No RBC in urinalysis
• HR ↑ because of pain/SNS
6) Ambulatory ECG monitoring
• Indications: syncope, near syncope or dizziness occurring on a near daily basis
○ Palpitations
○ Afib for assessment of rate or rhythm control
○ Ectopic or premature atrial beats
7) Severity of hypoxemia
• COPD → ↑ shunting → ↑ hypoxic vasoconstriction → pulmonary hypertension (loud S2/P2,
prominent pulmonary arteries, JVD)
8) No further tests are indicated
• Preoperative cardiac assessment includes: ECG, echo and stress test
• Stress test is only indicated when the patient has poor functional capacity: breathless or
chest pain with activity
9) Jarisch-Herxheimer reaction
• Treatment for syphilis (or other spirochetes [eg, lyme disease, leptospirosis]) → toxin release from killed bacteria
• Clinical findings: acute onset fever, chills, myalgia
10) Metformin
• Diabetic patients with comorbid pneumonia have ↑ risk of lactic acidosis if taking
metformin
• Metformin is also contraindicated in patients with liver failure, renal failure or sepsis
11) Surgical excision of apocrine tissue
• Occlusion of follicular pilosebaceous unit → Hidradenitis suppurativa
• Commonly affects intertriginous skin areas (eg, axilla, groin)
• Treatment is early radical excision of affected area
12) Hydration
• Preventative measures for contrast induced kidney injury: peri-procedural saline
hydration, use lowest volume of contrast agent, hold NSAIDs
13) Acyclovir
• Acute (<1 week) fever, altered mental status, or focal neurological symptoms are consistent
with HSV meningitis
• Treatment: Acyclovir
14) Airway compromise
• Tonsillitis with massive edema may occlude airway
15) Intravenous administration of 0.9% saline
• Treatment for suspected variceal hemorrhage: place 2 large bore IV (volume resuscitation),
IV octreotide, Abx → Endoscopic therapy
16) 80%
• 80 positive infections on new stool test
• 100 positive infections on gold standard biopsy
• Sensitivity = 80/100
17) Washing the area of involvement
• After a needle stick injury, a patient with immunization to Hep B does not need vaccine/booster, but should sterilize the area
18) Inflammation caused by release of cytokine by effector and memory T lymphocytes
• Type 4 delayed hypersensitivity
19) Corticosteroids therapy
• ↓ platelets <30,000 or symptoms of ITP → treat with corticosteroids, IVIG or splenectomy if refractory
• Megakaryocytes seen on bone marrow aspiration
20) Chlamydia trachomatis
• Tender boggy prostate, WBCs on urinalysis, ⊖ culture in young patient
• Intracellular indicates chlamydia (vs. gonorrhea)
21) Ulnar nerve compression
• Ulnar nerve (C8-T1) insult → hypothenar atrophy + interosseous muscle
dysfunction (ab/adduction of fingers [paper slipping from fingers])
22) Swallowing study
• Oropharyngeal dysphagia clinical presentation: Chronic cough after meals, mild dysarthria,
history of multi infarct dementia
• Dx: video fluoroscopic barium swallow
23) Iron
• Anemia with hypochromasia (central pallor) is consistent with iron deficiency anemia
• Not sideroblastic (no basophilic stippling seen)
• Not megaloblastic (no hyper-segmented neutrophils)
24) Serum protein electrophoresis
• Multiple myeloma: hypercalcemia, renal failure, anemia, bone lytic lesions
25) Subcutaneous administration of enoxaparin
• Evidence of DVT on ultrasound→ enoxaparin is the next best step
• Warfarin takes several days to work and is not the best treatment
26) Lisinopril
• ACEi → ↓ mortality in HFrEF (heart failure with reduced ejection fraction)
• Metoprolol and spironolactone would not work well in an acute setting because they could
↓ cardiac output (CO)
27) Administration of calcium gluconate IV
• Parathyroid gland removal post surgery → tetany, cramps, seizures
• Treatment of hypocalcemia: calcium gluconate/chloride
28) Rhabdomyolysis
• Barbiturates → immobility → ↑ CK, ↑ phosphate → AKI → blood detected on urine
dipstick, but absent on microscopy = rhabdomyolysis
29) Anaerobic empyema
• Right lower lobe infiltrate + foul smelling fluid indicates aspiration (likely anaerobes)
30) Begin lisinopril therapy
• ACEi use in a patient with diabetes & hypertension → ↓ mortality
• ACEi → ↓ diabetic nephropathy progression
31) Alveolar destruction and fibrosis
• FEV1/FVC ratio < 0.7 = Obstructive disease
• Emphysema → alveolar destruction (↓ DLCO) → ↓ breath sounds
32) Full thickness biopsy
• Possible malignancy: size > 6mm, asymmetry, multiple color
• Biopsy and excision if diagnosis confirmed
33) Serum calcium concentration
• Ranson Criteria for pancreatitis
○ WBC > 16K
○ Age > 55
○ Glucose >200 mg/dL
○ AST > 250
○ LDH > 350
34) Oral ibuprofen
• Diffuse ST elevation/PR depression, pleuritic chest pain relieved while sitting up, friction
rub are consistent with pericarditis
• Treatment = ibuprofen (1st line), colchicine and glucocorticoids (2nd line)
35) Allergic bronchopulmonary aspergillosis
• Hypersensitivity response to Aspergillus growing in lung mucus
• Associated with asthma
36) Urine free cortisol concentration in a 24 hour specimen
• Weight gain, hirsutism, truncal obesity, striae, irregular menses, acne are consistent with
37) Prepatellar septic bursitis
• Unaffected Range of motion = extra-articular
• Red, swollen area overlying patella + fever = bursitis complicated with infection
38) Insufficient inhibition of neutrophil elastase
• Obstructive lung X-ray, spirometry in young patient, andfather’s early diagnosis of
emphysema is consistent with a1 antitrypsin deficiency
39) ↓ K+, ↓ Cl-, ↑ pH
• Vomit → GI loss of HCL, production of HCO3- → RAAS activation from hypovolemia → Loss of K+, reabsorption of HCO3-
40) Avascular necrosis
• Steroid treatment of Vasculitis predisposes to avascular necrosis
• Crescent sign on MRI
41) Acute tubular necrosis
• ↓ urine output
• Granular casts
42) Pap smear + PCP prophylaxis
• PCP prophylaxis with TMP-SMX in CD4+ <200, thrush or history of PCP
• Pap smear CD4+ <500
43) Switch from glyburide and metformin to intermediate acting insulin
• Creatinine is elevated after initial treatment. Lactic acidosis from metformin → muscle pain,
nausea, SOB
• HBA1C + glucose is still elevated after metformin trial à switch to insulin
44) Adverse effect of verapamil
• Constipation
• Diabetic patient without neuropathy is unlikely to have neuropathy of colon
45) Subclavian steal syndrome
• Stenosis/occlusion of the proximal subclavian artery → reversal of blood flow in the
ipsilateral vertebral artery → upper extremity ischemia (pain, fatigue, paresthesias) and/or
vertebrobasilar insufficiency (dizziness, ataxia, disequilibrium)
46) Prerenal azotemia
• BUN/CR ratio >20:1, urine sodium <20 after diarrhea
47) Renal biopsy
• History of IVDU (IV drug abuse), Hepatitis, blood 3+, protein 4+, presence of dysmorphic
RBC = membranoproliferative glomerulonephritis
• Biopsy for DX
48) Cigarette smoking
• Greatest increased risk for MI
49) Recurrence of breast cancer
• Hypercalcemia of malignancy >14 (greater than primary hyperparathyroidism [12-14])
• Breast, gynecological, squamous cell, renal cell carcinoma → PTHrP secretion
• Metastasis → Breast, multiple myeloma, lymphoma
• ↑ 1,25 OH Vitamin D: lymphoma
50) Weight loss
• ↑↑ BMI is the number one cause of osteoarthritis
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