ODP094 Hypercalcemia caused by Mycobacterium Avium Complex, with Excellent Response to Intravenous Pamidronate

Abstract Background Hypercalcemia caused by granulomatous diseases such as sarcoidosis and tuberculosis, is a well-recognized entity. The pathophysiology of hypercalcemia associated with granulomatous diseases is related to increase conversion of 25 hydroxyvitamin D to its active form, 1,25 dihydroxyvitamin D, via extra-renal 1 -α hydroxylase activity. We present a patient with moderately sever hypercalcemia caused byMycobacterium Avium complex (MAC) infection in association with Human Immunodeficiency Virus (HIV) infection. Case Presentation The patient is 53-year-old male with longstanding HIV infection since 2003. He was referred to the endocrine clinic after an acute presentation to a local hospital in August 2021 with pancytopenia, lymphadenopathy, and hypercalcemia (corrected total calcium 13.8 mg/dl) with acute kidney injury. He was treated with intravenous fluids and subcutaneous Calcitonin injection. Endocrine work up showed low parathyroid hormone (PTH) at 3 pg/ml (14-95 pg/ml) and Parathyroid related peptide (PTHrP) level was Conclusion Mycobacterium Avium Complex infection is a possible cause of hypercalcemia, especially in immunocompromised individuals. Glucocorticoids, usually the first line treatment for acute hypercalcemia induced by 1,25 dihydroxyvitamin D overproduction, might not be appropriate in all patients. Alternatives include hydroxychloroquine, ketoconazole and parenteral bone anti- resorptive agents. Our patient had an excellent response to one dose of pamidronate. Ultimately his1,25 dihydroxy-vitamin D normalized with effective anti MAC therapy. Presentation: No date and time listed