Switch to atovaquone and subsequent re-challenge with trimethoprim-sulfamethoxazole for Pneumocystis prophylaxis in a kidney transplant population.

Kidney transplant recipients who are switched to atovaquone (ATO) from trimethoprim-sulfamethoxazole (TMP/SMX) for Pneumocystis jirovecii pneumonia (PJP) prophylaxis because of adverse events or complications may miss opportunities to be re-challenged with TMP/SMX, the first-line agent. This single-site, retrospective study assessed kidney transplant recipients for documented reasons for switching from TMP/SMX to alternate PJP prophylaxis and outcomes of TMP/SMX re-challenge. Out of 166 patients, 155 initially received TMP/SMX; of these, 31 were switched to ATO for various reasons. Fourteen patients receiving ATO were re-challenged with TMP/SMX; all were successfully re-initiated on TMP/SMX therapy. Most patients switched to ATO post kidney transplant secondary to non-hypersensitivity reasons should be re-challenged with TMP/SMX because of the advantages it provides over other agents.