NBME CBSE REAL EXAM 258 A+ QUESTIONS AND ANSWERS LATEST (usmle step 3)MEDICAL EXAMINATION

Prophy for close contacts of confirmed cases of meningococcal meningitis correct answers -rifampin 600 PO bid for 4 doses (2 days) -ciprofloxacin single dose (if pt is on OCPs b/c rifampin decreases effectiveness of OCPs) Standardized mortality ratio (SMR) correct answers SMR=observed # deaths/expected # deaths -adjusted measure of overall mortality -typically used in occupational epidemiology -mortality typically adjusted for age, gender, race, etc. Organism commonly associated with kidney stones correct answers Proteus When does a pt. require abx prophy for recurrent UTIs? correct answers Young female patients with at least 2 UTIs in six mos. or 3 UTIs in a year. Can give continuous prophy or just postcoital. Only pursue imaging if clinical evidence of obstruction. Biopsy evidence c/w celiac disease correct answers villus blunting (mucosal flattening), loss of normal villus architecture, increased lymphocytic infiltration of the mucosa Biopsy evidence c/w Crohn's correct answers transmural inflammation of the mucosa Biopsy evidence c/w ulcerative colitis correct answers superficial mucosal inflammation with infiltration of plasma cells Dietary recs for celiac correct answers NO: wheat, rye, barley OK: soybeans, corn, rice, potatoes Supplements: vit D, calcium, iron, folate (if deficient) Best initial test for pneumothorax correct answers UPRIGHT chest x-ray Primary HIV-associated thrombocytopenia (PHAT) correct answers -similar to ITP -affects 40% of HIV+ pts at some point -treat with zidovudine (AZT), which also decreases occurrence of opportunistic infections and Kaposi's sarcoma Henoch-Schonlein purpura correct answers -usually pediatric -acute abdominal pain -skin rash -joint inflammation Alcoholic ketoacidosis correct answers -AG acidosis -increased osmolal gap -ketonemia or ketonuria -variable blood glucose level, but if higher than 250 think DKA -tx with IVF (D5NS) and thiamine Adjustment of levothyroxine in pregnancy correct answers -INCREASE dose as soon as pregnancy is confirmed -most pt.s require increase of 25-50% -check TSH once a trimester -checking T3 and T4 not effective b/c these levels are increased during pregnancy due to increased thyroid-binding globulin Most common cause of primary hypothyroidism and best test for it correct answers -Hashimoto's thyroiditis -antimicrosomal (anti-TPO) ab level -radionuclide scan will show heterogeneous uptake of radioactive iodine, but this is not specific! Disease associated with thyroid lymphoma correct answers Hashimoto's thyroiditis -rapid increase in thyroid size and compressive symptoms in pt. with Hashimoto's: think thyroid lymphoma and get open thyroid bx Disease associated with hypothyroidism correct answers hyperlipidemia (usually just elevated LDL, but sometimes also elevated triglycerides) Good source of calcium in lactose-intolerant pt.s correct answers yogurt with live activated cultures (contains beta-galactosidase, which is tolerated by lactose-intolerant ppl)