Healing of osteitis fibrosa cystica after partial parathyroidectomy despite persistent parathyroid hyperfunction: a case report.

The diagnosis of primary hyperparathyroidism was made in a 55-year-old female with marked hypercalcemia (15 mg/100 ml) and hypercalciuria and skeletal x-rays showing typical lesions of subperiosteal resorption and numerous cystic areas. At surgery a left lower parathyroid adenoma presumably was totally excised. Serum calcium returned to normal levels immediately postoperatively, but 4 months after surgery hypercalcemia (11.5 mg/100 ml) was again found. During the following 18 months the patient was free of symptoms, and radiologic studies revealed complete healing of the subperiosteal resorption and repair of the bone cysts. Cortical bone mineral content also increased. However, elevated levels of serum parathyroid hormone (PTH) and calcium clearly indicated the persistence of primary hyperparathyroidism. Thus, a decrease in the degree of PTH hypersecretion permitted the repair of the skeletal lesions caused by a more severe level of parathyroid hyperfunction.