Purpose: We report our experience replacing trimethoprim-sulfamethoxazole (TMP/SMX) with aerosolized pentamidine (AP) in 22 children with acute leukemia who could not tolerate TMP/SMX.
Patients and methods: Children (age 1 to 15 years) with acute leukemia during maintenance chemotherapy or post-bone marrow transplantation (BMT) receiving prophylaxis for Pneumocystis carinii pneumonia (PCP) with TMP/SMX received AP following prolonged neutropenia or allergy to TMP/SMX. Patients received 300 mg of AP monthly (children < 4 years received 150 mg) dissolved in 5 mL of distilled water over 20 to 30 minutes.
Results: Over a 3-year period, 358 courses of AP were administered over 10,124 observable days. AP was adequately tolerated on a monthly basis for prophylaxis against PCP in 22 children with acute leukemia. AP was demonstrated to be effective in preventing PCP. There were minimal side effects observed during this trial. The majority of children with acute lymphoblastic leukemia (ALL; 12 of 14 [86%]) undergoing maintenance chemotherapy were able to resume full-dose therapy.
Conclusion: AP in children is well tolerated and shows high efficacy for PCP prophylaxis in children with leukemia. We conclude that AP should be considered as second-line PCP prophylactic therapy for children with acute leukemia in instances in which TMP/SMX cannot be tolerated. Phase III trials are required to determine its effect on dose intensification and event-free survival.