Low-dose trimethoprim-sulfamethoxazole safe, effective against PJP after kidney transplantation

Prophylactic treatment with trimethoprim (TMP)-sulfamethoxazole (SMX) at a low dose helps lower the risk of Pneumocystis jirovecii pneumonia (PJP) within 6 months following kidney transplantation, according to a study.

The study included 1,469 kidney transplant recipients, among whom 1,066 (72.56 percent) received 20-mg TMP plus 100-mg SMX daily, 127 (8.65 percent) received 20-mg TMP plus 100-mg SMX every other day, and 276 (18.79 percent) didn't have prophylaxis prescription.

Researchers looked at the incidence of PJP in the first 180 days of follow-up after kidney transplantation as the primary endpoint. They also evaluated changes in renal and liver function as secondary endpoints.

The nonprophylaxis, TMP-SMX daily, and TMP-SMX every other day groups had 124.92, 524.89, and 62.07 person-years of follow-up, respectively. During these periods, 29 patients developed PJP in the nonprophylaxis group; none of the patients in either TMP-SMX group did. The incidence rate of PJP in the nonprophylaxis group was 23.21 (95 percent confidence interval, 15.76–32.72).

Changes in renal and liver function did not significantly differ across the three groups (p>0.05).

Results were consistent in the propensity score matching (PSM) analysis, which included 111 patients in each group. PJP occurred only in the nonprophylaxis group, with 10 cases documented over 51.27 person-years of follow-up.

The findings suggest that TMP-SMX is an effective prophylaxis against PJP, an opportunistic and life-threatening fungal infection in kidney transplantation recipients.