Wenya Shan,1– 3 Liangping Wang,1,4 Jiayi Qin,1– 3 Wenhan Peng,5 Kuifen Ma1– 3 

1Department of Clinical Pharmacy, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China; 2Zhejiang Provincial Key Laboratory for Drug Evaluation and Clinical Research, Hangzhou, People’s Republic of China; 3Zhejiang Provincial Key Laboratory of Traditional Chinese Medicine for Clinical Evaluation and Translational Research, Hangzhou, People’s Republic of China; 4Department of Pharmacy, Hangzhou Linping District Hospital of Integrated Chinese and Western Medicine, Hangzhou, People’s Republic of China; 5Kidney Disease Center, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China

Correspondence: Wenhan Peng, Kidney Disease Center, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China, Tel +8687233411, Email 1198027@zju.edu.cn Kuifen Ma, Department of Clinical Pharmacy, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China, Email makuifen@zju.edu.cn

Background: The administration of trimethoprim-sulfamethoxazole (TMP-SMX) for the prophylaxis of Pneumocystis jirovecii pneumonia (PJP) has proven to be highly efficacious in individuals who have undergone kidney transplantation. Nevertheless, the potential for severe adverse reactions associated with this treatment cannot be overlooked, and the determination of an optimal dosage regimen continues to be a matter of investigation. The current study evaluated the effectiveness of low-dose TMP-SMX for PJP prophylaxis in kidney transplant patients and conducted an analysis of the clinical characteristics and epidemiological trends in patients with PJP infection.
Methods: This retrospective analysis studied electronic medical records of 1763 kidney transplant recipients from 2017 to 2020. These patients were initially prescribed a daily half-strength TMP-SMX (40 mg/200 mg), and the efficacy of this regimen was assessed during a follow-up period of 3– 51 months.
Results: Under our PJP prevention and adjustment strategy, 24 patients were infected with PJP. The overall morbidity of PJP infection in our study was 1.36%, corroborates with findings from previously published studies. Among these 24 patients, up to 87.5% had their dosage adjusted due to increased creatinine or other adverse reactions, the most frequent dose was daily quarter-strength TMP-SMX (20 mg/100 mg). TMP-SMX prophylaxis successfully postponed and distributed the onset of PJP, with the mean duration from transplantation to the occurrence of PJP being 13.50± 7.11 months.
Conclusion: Daily administration of half-strength TMP-SMX can effectively prevent PJP, and prolonging prophylaxis with this medication may potentially reduce the incidence of infection.

Keywords: efficacy, kidney transplant recipients, Pneumocystis jirovecii pneumonia, trimethoprim-sulfamethoxazole