Impact of Respiratory Coinfections on Outcomes of Pneumocystis jirovecii Pneumonia in Solid Organ Transplant Recipients.

BACKGROUND

Pneumocystis jirovecii pneumonia (PCP) is a significant opportunistic infection in solid organ transplant (SOT) recipients. However, the impact of respiratory coinfections on outcomes in this population remains unclear.

METHODS

We retrospectively analyzed 112 SOT recipients diagnosed with PCP from April 2018 to March 2024. Respiratory coinfections were defined as identification of significant pathogens in respiratory specimens within 3 days of PCP diagnosis.

RESULTS

Among 112 SOT recipients with PCP, 50.0% required intensive care unit (ICU) admission, and the 30-day and 90-day mortality rates were 12.5% and 17.9%, respectively. Respiratory coinfections were identified in 46 patients (41.1%), including cytomegalovirus (CMV, 30.4%), bacteria (14.3%), and non-CMV viruses (13.4%). Bacterial coinfection was significantly associated with increased 30-day mortality (adjusted odds ratio [aOR], 5.27; 95% confidence interval [CI], 1.15-26.27; p = 0.03) and 90-day mortality (aOR, 4.84; 95% CI, 1.29-19.35; p = 0.02). CMV coinfection was independently associated with prolonged hospital stay (adjusted ratio, 2.42; 95% CI, 1.67-3.50; p < 0.001), higher ICU admission rates (aOR, 2.95; 95% CI, 1.04-9.03; p = 0.05), and increased need for mechanical ventilation (aOR, 3.01; 95% CI, 1.10-8.83; p = 0.04), but not with mortality. Non-CMV viral coinfection was associated with significantly increased odds of ICU admission (aOR, 19.03; 95% CI, 2.67-254.90; p = 0.01) and mechanical ventilation (aOR, 21.21; 95% CI, 2.96-298.12; p = 0.01), without a significant impact on mortality.

CONCLUSION

In SOT recipients with PCP, bacterial coinfection was associated with higher mortality, while CMV and non-CMV viral coinfections were mainly associated with morbidity. Respiratory co-pathogens may indicate illness severity; whether pathogen-directed strategies can modify outcomes requires further study.