Comparison between the Outcomes of Pentamidine and Trimethoprim-Sulfamethoxazole for Pneumocystis Pneumonia in Non-HIV Patients: A Nationwide Japanese Retrospective Cohort Study.

Background Data on the first-line treatment options for patients with Pneumocystis pneumonia (PCP) without human immunodeficiency virus (HIV) infection are limited. Therefore, we evaluated the outcome of pentamidine compared to trimethoprim-sulfamethoxazole (TMP-SMX) in non-HIV patients with PCP. Methods We used data from the Japanese Diagnosis Procedure Combination Inpatient Database. We included non-HIV PCP patients who initially received TMP-SMX or pentamidine between July 2010 and March 2022. We categorized eligible patients into TMP-SMX and pentamidine groups and performed a propensity score overlap weighting analysis to compare in-hospital mortality between the groups. Results Among 5,870 eligible patients, 5,456 and 414 received TMP-SMX and pentamidine, respectively. Pentamidine treatment was associated with a higher in-hospital mortality than TMP-SMX treatment in the propensity score overlap weighting analysis (23.6% vs. 40.1%; risk difference, 16.5%; 95% confidence interval, 10.8-22.2%; p<0.001). Conclusions Based on these findings, pentamidine may not be as effective as TMP-SMX for treating PCP in non-HIV patients.