NBME Medicine Form 6 - Answers & Explanations
Updated: Mar 22, 2020
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)