Sarcoid-like granulomatous myositis-associated hypercalcemia. An infrequent case to consider
Thomas Uslar1, Roberto Olmos1,2, Jaime Godoy-Santin3
1Departamento de Endocrinología, Escuela de Medicina, Pontificia Universidad Católica de Chile, Chile.
Abstract:
PTH-independent hypercalcemia due to granulomatous disease is well-documented and sarcoidosis is the most characteristic disease, although there are others. We describe a case of sarcoid-like granulomatous myositis. An 87-year-old man was referred with tetraparesis and hypercalcemia (albumin-corrected calcium of 13.4 mg/dl) following a trip to the Caribbean. The evaluation showed a suppressed PTH, 25-hydroxy vitamin D of 7.5 ng/ml, 18F-FDG PET/CT showed markedly increased uptake in intercostal, back, shoulder, buttock and thigh muscles and a deltoid biopsy confirmed extensive granulomatous myositis. He was prescribed glucocorticoids which resulted in normalized plasma calcium levels and complete recovery from tetraparesis. Sarcoid-like granulomatous myositis should be incorporated into the differential diagnosis of PTH-independent hypercalcemia, especially in the absence of clinical features of sarcoidosis and with special emphasis on the use of 18F-FDG PET/CT to ensure a correct approach.

