NBME Medicine Form 5 - Answers & Explanations
Updated: Mar 6, 2020
Editor: Jordan Abrams
1) Valvular insufficiency of deep veins
● Mild edema due to incompetent valves + varicose veins due to saphenous vein reflux + area of hyperpigmentation (stasis dermatitis) over left ankle
2) Not eating mahimahi
● Histamine toxicity (scombroid poisoning) symptoms resembling anaphylaxis: flushing, headache and light-headedness (may also see urticaria, itching)
● Symptoms generally present within 10 minutes of eating dark-meat fish (eg, mahimahi)
3) Antihypertensive therapy
● HTN is greatest risk factor for both ischemic and hemorrhagic stroke (~4x the risk of a CVA compared to a normotensive individual)
● HTN → ↑ shearing forces on vascular endothelium → exacerbated atherosclerosis
4) Toxic adenoma of thyroid gland
● Toxic thyroid adenoma (hyper-functioning thyroid nodule) → hyperthyroidism sxs (eg, weight loss, palpitations, heat intolerance, fatigue, tachycardia, etc.)
● Labs: ↓ TSH, ↑ free T3 & T4, ↑ radioactive iodine (RAI) uptake in a single nodule
● DDx: ○ Subacute (de Quervain) thyroiditis would have a tender/painful goiter
○ Graves disease would show ↑ RAI uptake in diffuse pattern
○ Toxic multinodular goiter would ↑ RAI uptake in multiple nodules
5) Penicillin
• Painless chancroid on glans of penis is characteristic of Syphillis
6) Pancreatic adenocarcinoma
● Pancreatic tumor can commonly compress and dilate pancreatic duct and common bile duct (double duct sign) → ↑ ALP and ↑ Direct Bilirubin
● Unexplained migratory thrombophlebitis can also commonly be seen in Pancreatic Adenocarcinoma
7) B-Thalassemia trait
● ↓ synthesis of Beta chains → ↑ HbA2 (2 alpha chains, 2 delta chains)
● Beta Thalassemia trait is most often asymptomatic in presentation
8) Tuberculosis
● Common Tuberculosis symptoms include fever, chills, hemoptysis
● Reactivation Tuberculosis preferentially affects the apices of the lung
9) Catheterization of bladder
● Bladder obstruction/distention commonly presents with dysuria and a tender suprapubic mass
● Treatment → Catheterization to relieve obstruction and void distended bladder
10) Complete Heart block
● P waves and QRS complexes are not associated with one another
● R-R interval is also regular
11) Hypomagnesemia
● Severely hypomagnesemia → suppressed PTH → hypocalcemia
● Alcoholism may lead to hypomagnesemia
12) Add simvastatin to her current regimen
● Age 40-75 with Diabetes Mellitus → Statins are indicated
● Statins blocks rate limiting enzyme (HMG-CoA Reductase) in cholesterol production
13) Hematogenous dissemination of distant infection
● Pott disease (extra-pulmonary tuberculosis)
● hematogenous seeding of a distant infectious focus → infection of the vertebral bone → contiguous spread to the intervertebral discs and adjacent vertebrae
14) Adequate control of blood pressure
● HTN → left ventricular hypertrophy (LVH) and ↓ ejection fraction (EF)
● Blood pressure control can prevent further permanent damage to heart
15) Tracheomalacia
● Weakening of supporting tracheal cartilage → collapse of trachea upon expiration
● Long term intubation → tracheal weakening and structural damage of tracheal cartilage
16) Cor Pulmonale
● Impaired function of the right ventricle (RV) due to pulmonary hypertension (pulmonary systolic pressure >25 mmHg)
● Symptoms: dyspnea, fatigue, exertional angina
● Signs: JVD, ascites, hepatomegaly, and pitting edema
17) 0.9% Saline
● Administration of IV Isotonic Saline prior to CT can generally help to restore renal perfusion and prevent renal damage via IV contrast (contrast nephropathy)
18) Nephrogenic diabetes insipidus
● Hypercalcemia can induce nephron damage → diabetes insipidus (DI) → polyuria, polydipsia, dehydration and volume depletion
● Nephrogenic DI → Failure of the kidney to respond to ADH
19) Crohn's disease
● Crohn’s Disease is characterized by chronic abdominal pain, diarrhea, weight loss and evidence of inflammation
20) Hot tub use
● Hypersensitivity pneumonitis caused by Mycobacterium avium complex (hot tub lung)
21) Add fluticasone
● Mild persistent asthma → add ICS (inhaled corticosteroid) to SABA (short acting beta agonist [eg, albuterol PRN])
22) Lymphangitis
● Lymphangitis → Inflammation of lymphatic channels that occurs as a result of infection or trauma at a site distal to the channel
● It will generally follow a pattern of red track marks along lymphatics
● Infection → ↑White Blood Cell (WBC), Left Shift, fever
23) Serum anti mitochondrial antibody assays
● Primary biliary cholangitis (PBC) characteristically presents with ↑ anti-mitochondrial antibodies and cholestatic pattern of liver injury (↑↑ ALP, ↑ AST and ALT) in middle-aged women
● Pathogenesis: autoimmune destruction of small bile ducts → intrahepatic cholestasis
● Presents insidiously with fatigue and pruritus
24) CT scan of abdomen
● ↑↑ Dehydroepiandrosterone (DHEAS) and no suppression of cortisol after overnight dexamethasone → Adrenal origin
● CT scan of abdomen to visualize Adrenal tumor secreting DHEAS
25) Alendronate
● Long term treatment of osteoporosis → bisphosphonates, calcium and vitamin D supplementation
● Bisphosphonates inhibit osteoclast activity
26) Nitrofurantoin therapy
● Treatment of uncomplicated cystitis → nitrofurantoin, trimethoprim-sulfamethoxazole (TMP-SMX), or Fosfomycin
27) Acute respiratory distress syndrome
● Acute Respiratory Distress Syndrome (ARDS) → Non - Cardiogenic lung injury → Inflammation → fluid leakage into alveoli
● Bilateral lung opacities are generally seen on Chest X- Ray
● Common risk factor for ARDS → trauma (i.e. Intubation)
● ARDS can present with hypoxemia with a PaO2/FiO2 ratio < 300mmHG