Identification of Predictive Markers and Outcomes of Late-onset Pneumocystis jirovecii Pneumonia in Kidney Transplant Recipients

Background. In the era of prophylaxis, Pneumocystis pneumonia (PCP) has become a late-onset opportunistic infection requiring indications for prolonged prophylaxis to be defined. The primary objective of our study was therefore to evaluate risk factors associated with late-onset PCP. The secondary objective was to assess the impact of this infection on graft and patient survival. Methods. We conducted a French case-control study in Bordeaux and Toulouse center by matching 1 case to 1-2 controls from the same center based on the transplant date and the type of induction treatment. Results. Seventy cases and 134 controls were included. PCP occurred at a median of 3 years after transplantation. The total lymphocyte count and CD4(+) and CD8(+) T-lymphocyte values were lower in the cases than in their matched controls on the day of infection and annually up to 4 years earlier. The covariables independently associated with PCP were the total lymphocyte count 1 year before Pneumocystis, mTOR inhibitors used as maintenance immunosuppressive drugs, and the administration of corticosteroid boluses used in acute rejection. A total lymphocyte count threshold <1000/mu L offered the best predictive value for infection occurrence. PCP was associated with high incidence of graft loss and patient death (30% and 17% respectively, 3 years after PCP). Conclusions. Pneumocystis pneumonia has dramatic consequences in kidney transplant recipients; a targeted prophylaxis based on simple criteria, such as chronic lymphopenia and/or history of corticosteroid boluses, could be useful to avoid life-threatening complications.

Automated summary

Late-onset Pneumocystis pneumonia (PCP) occurring approximately 3 years after transplantation is associated with risk factors such as low total lymphocyte count, use of mTOR inhibitors as maintenance immunosuppressive drugs, and administration of corticosteroid boluses for acute rejection. PCP is linked to high incidence of graft loss and patient death, highlighting the need for targeted prophylaxis based on simple criteria to prevent life-threatening complications.