Hungry bone syndrome: A case report and review of the literature

Abstract

A case of hungry bone syndrome (HBS) and changes in bone density is presented. Clinical, laboratory, and radiologic findings of this patient undergoing massive calcium therapy to prevent hypocalcemia are also described. A 31 year-old-man with chronic renal failure underwent parathyroidectomy for parathyroid hyperplasia. His postoperative course was characterized by prolonged hypocalcemia, hypophosphatemia, and risk for tetany due to massive calcium deposition in the bone. Although in most cases HBS is asymptomatic, it may present with severe bone pain and cause death due to tetany. We report a case of severe HBS after parathyroid surgery that demonstrated large increases in hip and lumbar bone density during recovery. Lumbar (L2–L4) bone density increased by 16% (from 1.137 to 1.329 g/cm 2, Z-score 94% to 109%) over an 8-month period. In comparison, left femoral neck bone density increased by 37% (from 0.962 to 1.314 g/cm 2, Z-score 92% to 125%) over the same period. This case reports describes the massive amounts of calcium that are required in the treatment of HBS. A large increase in bone density over a short period of time indicates that endocrine and nutritional conditions allow for rapid bone deposition even in a patient with chronic renal failure. Understanding the bone physiology mechanism(s) responsible for the rapid increase in bone density may advance treatments for osteoporosis.