Six‐month risk of Pneumocystis pneumonia following acute cellular rejection: A case‐control study in solid organ transplant recipients

Background Solid organ transplant (SOT) recipients are at risk of Pneumocystis pneumonia (PCP). PCP is associated with significant morbidity and mortality. The effect of acute T cell‐mediated rejection (TCMR) on post‐transplant PCP has not been determined yet. Methods In this case‐control study, we estimated the risk of PCP following acute TCMR during a lookback period of 180 days. We also determined the effects of contributing factors such as CMV infection. Results We compared 15 SOT (8 kidney, 4 heart, 2 liver, and 1 kidney‐pancreas) recipients with PCP with 60 matched recipients who did not develop PCP (control group) during the study period (December 2013 to February 2016). PCP occurred after a complete course of prophylaxis (ie, late‐onset PCP) in 60% of patients. Patients with PCP frequently required intensive care unit (ICU) admission (73.3%). Post‐transplant PCP was associated with considerable allograft loss (53.4%) and mortality (26.7%). In the 6‐month lookback period, acute TCMR (OR: 13.1, 95% CI: 3.2, 53.2), and CMV infection (OR: 15.1,95% CI: 4.0, 53.2.1) were significantly associated with post‐transplant PCP. Conclusions Post‐transplant PCP is associated with substantial risk of ICU admission, allograft failure, and mortality. Anti‐ Pneumocystis prophylaxis for at least 6 months following acute TCMR may reduce the risk.