Endocrine Abstracts

JOINT3468

Introduction: Hypocalcemia is a common problem after parathyroidectomy. When high-turnover bone disease is suddenly corrected by the reduction in parathyroid hormone (PTH) after surgery, reduced bone resorption and increased bone formation can cause insistent hypocalcemia.

Case: A 49-year-old female patient was admitted to our clinic with weakness, fatigue, polydipsia, polyuria, and constipation. She lost 5 kilos in the last 6 months. Her tongue was dry. She had elevated creatinine, alkaline phosphatase (ALP), and calcium (Ca) levels, and her phosphorus (P) level was decreased. She had serious hypercalcemia (Ca: 16,18 mg/dL) electrocardiography (EKG) was performed. There was no arrhythmia, but short QT was present (QTc:330 msn). Oral and İntravenous (iv) hydration was given. PTH, and 24-hour urinary Ca were elevated too. And 25 hydroxy vitamin D and glomerular filtration rate (GFR) was decreased. She had 9 to 29 liters of urine, and she had nephrogenic diabetes insipidus due to hypercalcemia. A 30*20*35 mm parathyroid adenoma was seen at ultrasonography and Tc-99 MIBI parathyroid scintigraphy also confirmed the parathyroid pathology. Subperiosteal bone resorptions, the ‘salt and pepper’ appearance, and brown tumors were seen in X-rays. Zoledronic acid 4 mg was administered, and surgery was. Her PTH was 12,5 ng/l, Ca was 7,13 mg/dl, P was 1,82 mg/dl, and Mg was 1,51mg/dl. Both Trousseau’s and Chvostek’s signs were positive. Iv and oral Ca replacement were initiated active vitamin D (calcitriol) was started and 25-OH vitamin D that started before the operation was continued. After 7 days of operation, she had hip pain. Bilaterally femur fracture was detected at radiography. And she underwent surgery. After 15 days, despite of 10 g oral calcium carbonate per day and 1,5 mg of oral calcitriol per day, the iv-calcium requirement continued. Calcitriol gradually increased to 4 mg per day and iv-calcium requirement decreased. After 54 days she was discharged. 6 months after surgery, oral calcium and calcitriol were still required.

Conclusion: Although the lack of well-defined clinical criteria for the diagnosis of hungry bone syndrome makes it difficult to determine its true incidence. It is an acute clinical condition characterized by hypocalcemia, hypophosphatemia and hypomagnesemia. Ca drops to its lowest level in 36 hours after operation. It is temporary and although it usually improves within a few weeks it can continue longer. It is important to closely monitor these patients during replacement therapy to avoid iatrogenic hypercalcemia and related complications.

Key words: Hypocalemia, parathyroidektomi