A 64-year-old woman presents with fatigue and bone pain. Vital signs: BP 128/82, HR 88, RR 16, Temp 37.2°C, SpO2 98% on room air. Laboratory studies show serum calcium 10.4 mg/dL, PTH 78 pg/mL, and 1,25-dihydroxyvitamin D elevated at 68 pg/mL (normal 20-50). Chest X-ray demonstrates bilateral hilar lymphadenopathy. Parathyroid imaging is unremarkable. Which diagnosis best explains these findings?

  1. A)Vitamin D intoxication from supplements
  2. B)Sarcoidosis with extrarenal 1-alpha hydroxylase productionGABARITO
  3. C)Primary hyperparathyroidism
  4. D)Tertiary hyperparathyroidism
  5. E)Hyperthyroidism with secondary PTH elevation

Explicação

Sarcoidosis causes granulomatous inflammation in which activated macrophages produce 1-alpha hydroxylase, converting 25-hydroxyvitamin D to active 1,25-dihydroxyvitamin D. This causes hypercalcemia and suppresses PTH, but the elevated PTH and elevated 1,25-vit... Ver explicação completa e trilha adaptativa →

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