Unusual recurrence of hypercalcemia due to concurrent parathyroid adenoma and parathyroid sarcoidosis with lymph node involvement.

Objective: To describe a patient presenting with the rare findings of synchronous parathyroid adenoma and parathyroid sarcoidosis.

Methods: We describe the clinical history, physical examination findings, laboratory values, imaging findings, and pathologic data of a man who developed recurrent severe hypercalcemia after successful parathyroidectomy.

Results: A 67-year-old man had the following initial blood test results: calcium, 11.1 mg/dL (reference range, 8.5-10.6 mg/dL); albumin 4.0 g/dL (reference range, 3.2- 5.2 g/dL); intact parathyroid hormone, 166 pg/mL (reference range, 10-69 pg/mL); creatinine, 1.9 mg/dL; 25-hydroxyvitamin D, 15 ng/mL (reference range, 30-80 ng/mL); and 1,25-dihydroxyvitamin D, 44 pg/mL (reference range, 16-72 pg/mL). Chest x-ray was normal, and delayed images from a technetium Tc 99m sestamibi scan showed increased activity in the right lower pole of the thyroid. Two months after successful parathyroidectomy, the patient was admitted to the hospital with a serum calcium concentration of 17 mg/dL. Pathologic examination of the resected gland confirmed the diagnosis of parathyroid adenoma, and subsequent review disclosed the presence of noncaseating granulomas within the adenoma.

Conclusions: Sarcoidosis with parathyroid involvement causing severe hypercalcemia is unique to this case. Recurrent hypercalcemia after successful resection of a parathyroid adenoma may require consideration of potential causes other than the initial diagnosis.