Diabetes Mellitus USMLE Step 1 Practice Question
A 70-year-old woman with limited sun exposure and poor nutritional intake presents with diffuse bone pain and proximal leg weakness. Vital signs: BP 138/82, HR 88, RR 16, Temp 37°C, SpO2 98% on room air. Laboratory studies reveal serum calcium 7.2 mg/dL, phosphate 2.1 mg/dL, alkaline phosphatase 95 U/L, and PTH 185 pg/mL. 25-hydroxyvitamin D is severely reduced. Cognitive function remains intact. Which diagnosis best explains these findings?
Answer choices
- APrimary hyperparathyroidism
- BPseudohypoparathyroidism
- CThyrotoxicosis
- DPaget disease of bone
- EVitamin D deficiency osteomalaciaCorrect answer
- FChronic kidney disease with secondary hyperparathyroidism
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