Diabetes Mellitus USMLE Step 1 Practice Question
A 52-year-old man with central obesity, hypertension, and acanthosis nigricans presents with polyuria and polydipsia. Vital signs show BP 148/92 mmHg, HR 88/min, RR 16/min, temperature 37°C, and SpO2 98% on room air. Laboratory studies reveal hemoglobin A1c of 9.2% and fasting glucose of 256 mg/dL. Urinalysis shows no ketones. Early in the course of his disease, which of the following laboratory findings is most likely?
Answer choices
- AAbsent C peptide due to autoimmune beta cell destruction
- BHigh anti glutamic acid decarboxylase antibodies and low insulin
- CLow glucagon due to alpha cell failure
- DSevere ketonemia due to absolute insulin deficiency
- EElevated C peptide with peripheral insulin resistanceCorrect answer
- FElevated fasting glucagon with normal C peptide levels
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