*Purpose: Trimethoprim-sulfamethoxazole (TMP-SMX) is preferred therapy for pneumocystis pneumonia (PJP) prophylaxis in solid organ transplant (SOT) recipients, however, use can be limited by allergy and intolerance. Inhaled Pentamidine (IP) is used as second line prophylaxis in those who are unable to receive TMP-SMX. The purpose of this study was to describe the characteristics and outcomes of IP for PJP prophylaxis in SOT recipients.

*Methods: IRB-approved, retrospective descriptive study of SOT recipients across a health system prescribed IP for PJP prophylaxis between January 2017 to November 2019. Patients were included if they were ≥18 years old treated with IP for &gt 1 dose after SOT. Exclusion criteria: pregnancy, developmental delay, prisoners, and patients with graft versus host disease. Primary outcome was the proportion of patients with breakthrough infections. Secondary outcomes included indication and adverse effects.

*Results: 80 subjects were included (7 multivisceral; 18 lung; 24 liver; 31 kidney). Median [IQR] age was 62.5 [54-68.5] years. Total of 504 pentamidine doses were administered with median doses of 6 [4-6]. Indications included 50 (62.5%) intolerance 29 (36.3%) allergy, and 1 (1.2%) multidrug resistant organism colonization. Breakdown of specific intolerances and allergies are listed in Table 1 (some patients had multiple indications). No breakthrough infections were seen. 7 (14%) patients with intolerance were rechallenged with TMP-SMX. 4 (13.7%) with an allergy were rechallenged with TMP-SMX and 2 (6.9%) received an allergy consultation. Overall, 46 (57.5%) patients experienced adverse effects. Breakdown of total adverse effects (n=75): cough/chest tightness/wheezing 58, bronchospasm 13, hypo- or hyperglycemia 2, unanticipated seeking of care for respiratory issue 2.

*Conclusions: IP appeared to be effective; however, tolerability was suboptimal with 57.5% experiencing at least 1 adverse effect. 6.9% of patients with an allergy received an allergy consultation. 14% thought to be intolerant were rechallenged. The results of this study suggest more efforts are needed to properly assess TMP-SMX allergies prior to SOT and to re-evaluate institutional algorithms.

« Back to 2020 American Transplant Congress