The side effect profile of sirolimus and its relationship with some variables: A retrospective study of Iranian renal transplant patients.

Background: Sirolimus is a potent immunosuppressive in renal transplantation. However, its use is limited by some reported side effects. The objective of this study was to determine the side effect profile of sirolimus in renal transplant patients.

Materials and methods: In the present study, we retrospectively reviewed the medical records of 116 renal transplant patients treated with sirolimus alone or in combination with other immunosuppressive agents at private therapeutic centers in Isfahan, Iran, between March 2009 and February 2020. A checklist was used to collect data on demographic and clinical variables. Data were analyzed with independent samples t-test and Chi-squared test.

Results: Our findings indicated that the most prevalent sirolimus-related side effects were edema (42.3%), proteinuria (37.5%), cytopenia (26.9%), abnormal level of liver enzymes (11.7%), and pneumonitis (9.7%). Stratification of side effects by sirolimus dose (<2 mg and ≥2 mg) demonstrated their dose-independent occurrence (P > 0.05). Pneumonitis was the most frequent reason for sirolimus cessation (58.7%). No significant differences were observed between males and females regarding the frequency of reasons for sirolimus cessation (P > 0.05).

Conclusion: Edema, proteinuria, cytopenia, abnormal level of liver enzymes, and pneumonitis were the most prevalent sirolimus-related side effects in renal transplant patients. Further prospective cohort studies are warranted to detect underlying mechanisms and determinants of these side effects in renal transplant patients treated with sirolimus.