A 36-year-old man with end-stage renal disease secondary to hypertensive nephrosclerosis had a two-day history of epigastric pain and nausea. Soon after admission, multiple grand mal seizures uncontrolled by intravenous phenytoin sodium and diazepam developed. His calcium level was 14 mg/dL and his amylase level was 2,230 mg/dL; lumbar puncture was normal. Hemodialysis lowered his calcium level to 10.7 mg/dL but failed to control his seizures. Secondary hyperparathyroidism was thought to be the cause of his malignant hypercalcemia, and an emergency subtotal parathyroidectomy was performed. Postoperatively, his grand mal seizures resolved. Confusion and aphasia also developed, but they resolved over the ensuing three weeks. Microscopic examination of the parathyroid glands revealed diffuse chief cell hyperplasia. Preoperative parathormone level was 2,196 pg/dL (normal, < 450 pg/dL). A review of the literature has failed to reveal a similar case.
(Arch Intern Med 1981;141:1549-1550)