Impaired thymic function and CD4Â + T lymphopenia, but not mannose-binding lectin deficiency, are risk factors for Pneumocystis jirovecii pneumonia in kidney transplant recipients

In conclusion, PCP risk was associated with higher age and related to both thymic functional impairment and long-lasting CD4 + T-lymphopenia that started already before transplantation. Despite frequent occurrences in KTR, low levels of serum MBL were not associated with increased risk for PCP. CD4 + T-cell counts and function should be addressed in prospective studies for more individualized approaches to PCP prophylaxis.