Hypercalcaemia and elevated 1,25(OH)(2)D(3) levels associated with disseminated Mycobacterium avium infection in AIDS.

Hypercalcaemia may complicate granulomatous diseases, such as tuberculosis and sarcoidosis, and various AIDS-related opportunistic infections and malignancies. We report here two patients with AIDS and disseminated Mycobacterium avium infection who developed symptomatic hypercalcaemia several weeks after commencing antimycobacterial chemotherapy, and in whom inappropriately elevated 1,25(OH)(2)D(3)levels were documented. Although vitamin D supplementation may have contributed, no other cause for the hypercalcaemia was found. The biochemical and clinical similarities between these cases and other hypercalcaemic granulomatous diseases suggest a common mechanism related to macrophage activation and dysregulated vitamin D production.