Electrolyte Disorders USMLE Step 1 Practice Question
A 67-year-old man with metastatic squamous cell carcinoma of the lung presents with constipation, abdominal pain, polyuria, and confusion. Vital signs: BP 148/92 mmHg, HR 102 bpm, RR 18, Temp 37.2°C, SpO2 98% on room air. Laboratory studies show serum calcium 13.9 mg/dL, phosphate 2.2 mg/dL, and albumin 3.8 g/dL. Serum PTH is suppressed. Which symptom cluster best characterizes this electrolyte disorder?
Answer choices
- AHyperreflexia, clonus, agitation, and hyperthermia
- BTetany, seizures, prolonged QT, and laryngospasm
- CHeadache, confusion, coma, and seizures from water intoxication
- DBradycardia, hyporeflexia, respiratory depression, and flushing
- EStones, bones, groans, thrones, and psychiatric overtonesCorrect answer
- FPrimary hyperparathyroidism with elevated intact PTH
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