USMLE Step

Notes

•Last-Minute HY Concepts (Quick Review) for USMLE Step 1 PHARMACOLOGY Acetaminophen: hepatotoxic via NAPQI; treat with N-acetylcysteine. Aminoglycosides: ototoxic and nephrotoxic. Beta-blockers: contraindicated in asthma. Atropine: antidote for organophosphate poisoning; may cause hyperthermia. MICROBIOLOGY S. aureus: coagulase-positive, catalase-positive, causes abscesses. C. difficile: causes post-antibiotic diarrhea; treat with oral vancomycin or fidaxomicin. N. meningitidis: prophylaxis with rifampin. Picornaviruses: +ssRNA, non-enveloped, replicate in the cytoplasm. CARDIOLOGY MI ECG: ST elevation and T inversion; check leads for affected region. Common murmurs: - Systolic murmur in aortic stenosis. - Diastolic murmur in mitral stenosis. Shock types: - Septic: decreased SVR, increased CO. - Cardiogenic: increased SVR, decreased CO. ENDOCRINE Type 1 DM: autoimmune destruction of beta cells. Insulin: increases glucose uptake, decreases gluconeogenesis. Cushing syndrome: high ACTH, indicating a central cause (adenoma or paraneoplastic). BIOCHEMISTRY / METABOLISM Glycogenolysis: G6Pase deficiency causes Von Gierke disease. Urea cycle: O...