An unexpected cause of severe and refractory PTH-independent hypercalcemia: case report and literature review.

Hypercalcemia is a common condition in the internal medicine practice. Sometimes its cause is not readily apparent, so extensive investigation is appropriate. Here we report an unexpected cause for hypercalcemia in an elderly woman. The case of an 82-years old woman with PTH-independent hypercalcemia, lymphocytosis, normal serum 1,25 (OH)vitamin D levels, and low serum PTHrp levels, is described. Medical history and complementary investigation were unremarkable, except for increased metabolic activity in the glutei regions, as measured by whole body 18F-FDG PET-CT. Reviewing her medical history, her sister recalled that she had been submitted to intramuscular methylmethacrylate injections, for cosmetic purposes, five years before presentation, which was confirmed by muscle biopsy. Low calcium intake, parenteral bisphosphonates, calcitonin, and glucocorticoids were used to control serum calcium levels. Methylmethacrylate injections, used cosmetically, are a new cause for hypercalcemia, even after many years. Hypercalcemia was probably due to calcitriol overproduction in foreign body granulomas. Persistent reactive lymphocytosis could be a clue for this inflammatory cause of hypercalcemia.