Retrospective review of intravenous pentamidine for Pneumocystis pneumonia prophylaxis in allogeneic hematopoietic stem cell transplantation

Background Patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) are at risk of numerous opportunistic infections. Pneumocystis jirovecii pneumonia (PJP) is a potentially life-threatening infection that can develop in immunocompromised individuals. Current prophylaxis for PJP includes trimethoprim-sulfamethoxazole (TMP-SMX), dapsone, atovaquone, or inhaled pentamidine (PEN), often with varying breakthrough rates. The use of intravenous (IV) PEN for PJP prophylaxis has been evaluated in pediatric patients. Methods A single-institution retrospective review of electronic medical records was conducted for patients who underwent allo-HSCT between January 2001 and May 2013 and who had received at least 1 dose of IV PEN for PJP prophylaxis. Data collected included patient demographics, diagnosis, previous chemotherapy, pre-transplant conditioning regimen, other medications, microbiology test results, and clinical outcomes. Results A total of 113 patients were included in the study. The median number of PEN doses administered per patient was 3 (range 1–23). IV PEN was primary PJP prophylaxis in 74 of the patients (65%) and second-line prophylaxis in 39 (35%) post transplant, with the majority switching from oral TMP-SMX. Side effects of IV PEN administration were minimal. No patients who received IV PEN prophylaxis developed PJP infection. No case of PJP was seen in patients who received other agents for PJP prophylaxis. Conclusion This retrospective study showed that IV PEN is very effective and well-tolerated prophylaxis for PJP; IV PEN can be considered a favorable alternative for PJP in situations where other agents might be contraindicated. Our findings provide strong support for prospective studies of IV PEN for PJP prophylaxis in adult HSCT recipients.