Hypercalcaemia as a prodromal feature of indolent Pneumocystis jivorecii after renal transplantation.

Following renal transplantation, hypercalcaemia is frequently caused by persisting hyperparathyroidism. Unregulated extrarenal 1,25-dihydroxyvitamin D (1,25(OH)(2)D) synthesis, which is well recognized as a cause of hypercalcaemia in granulomatous diseases, may also occur after kidney transplantation. This mechanism is also likely to be responsible for hypercalcaemia reported during treatment of cytomegalovirus and associated with acute symptomatic pneumocystis jivorecii pneumonia (PCP). Hypercalcaemia as a prodromal feature of indolent PCP has not been described. We report a renal transplant recipient who developed hypercalcaemia 30 months post-transplant due to extrarenal production of 1,25(OH)(2)D. Two months later, PCP was diagnosed and hypercalcaemia resolved after initiation of treatment.