Diabetes Mellitus USMLE Step 1 Practice Question
A 72-year-old man with type 2 diabetes mellitus is brought to the emergency department with lethargy and severe dehydration after several days of pneumonia. Laboratory studies show glucose 890 mg/dL, serum osmolality markedly elevated, bicarbonate 21 mEq/L, pH 7.37, and minimal serum ketones. Which of the following is the most likely diagnosis?
Answer choices
- AHyperosmolar hyperglycemic stateCorrect answer
- BSIADH
- CAdrenal crisis
- DLactic acidosis from metformin
- EDiabetic ketoacidosis
- FHypoglycemic hyperosmolar coma
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