Hidden Culprit of Primary Hyperparathyroidism

Abstract

A 46-yr-old female with recurrent primary hyperparathyroidism (PHPT) subsequent to the removal of five parathyroid glands was evaluated for iron-deficient anemia. Because an obvious cause of blood loss was absent, upper gastrointestinal endoscopy was performed as part of the examination. Subsequently, a small polyp (8 11 mm) was incidentally found on the patient’s right pyriform sinus. The biopsy specimen of the polyp showed hyperplasia of an ectopic parathyroid gland. At age 34, the patient was diagnosed with multiple endocrine neoplasia type 1 because she presented with PHPT, nonfunctioning pituitary, and pancreatic neuroendocrine tumors. The patient had a family history of PHPT (brother). Serumconcentrationsof calciumand intact PTH at diagnosis were 12.2 (normal, 8.8–10.2) mg/dl and 206 (normal, 10– 65) pg/ml, respectively. She underwent parathyroidectomy of three enlarged, eutopic, parathyroid glands (right superior, 230 mg; left superior, 117 mg; and left inferior, 316 mg) and one ectopic gland (260 mg) in the mediastinum. A right inferior parathyroid gland, which looked normal in size, was left in situ. The pathology report revealed that all resected lesions were parathyroid hyperplasia. Postoperatively, the patient’s serum concentrations of calcium and intact PTH were 8.0 mg/dl and 48.5 pg/ml, respectively,