Pneumocystis jirovecii Pneumonia in Kidney Transplant Recipients Receiving Belatacept: A Report of Two Cases With Atypical Presentations.

Immunosuppressive therapy after kidney transplantation is associated with an increased risk for the development of opportunistic infections, such as Pneumocysti s jirovecii pneumonia (PJP). Belatacept, a selective costimulatory blocker that prevents T cell activation, was previously suggested to be a potential risk factor for PJP development in kidney transplant recipients. We present 2 cases of kidney transplant patients with PJP discovered unexpectedly during a diagnostic work-up for fever of unknown origin. Both patients lacked typical clinical findings such as hypoxia, ground-glass pattern on computed tomography, or suggestive biochemical alterations such as high lactate dehydrogenase levels or hypercalcemia. PJP should therefore be included in the differential diagnosis when evaluating fever in kidney transplant recipients receiving belatacept, even in the absence of typical pulmonary and laboratory findings.