Objective: This study was conducted to determine the efficacy of dosing trimethoprim/sulfamethoxazole on 2 consecutive days per week for the prevention of Pneumocystis carinii (jiroveci) pneumonia in a pediatric leukemia and lymphoma population and to determine whether trimethoprim/sulfamethoxazole contributes to neutropenia during maintenance therapy.
Methods: Charts were reviewed for all pediatric patients with leukemia and lymphoma diagnosed between January 1, 1993, and December 31, 2002. Data were collected through April 1, 2004.
Results: A total of 575 charts were reviewed; 529 patients were included in the analysis. A total of 482 (345 leukemia, 137 lymphoma) patients were evaluated on trimethoprim/sulfamethoxazole dosed 2 consecutive days per week for 268074 patient-days. No breakthrough cases were documented in compliant patients; 2 noncompliant patients developed P. carinii pneumonia. A total of 238 patients who were on trimethoprim/sulfamethoxazole prophylaxis and 13 patients who were receiving an alternative medication prophylaxis were evaluated for neutropenia during maintenance therapy. The median number of maintenance days on trimethoprim/sulfamethoxazole was 605.5 days and on alternative drug was 617 days. The median number of neutropenic maintenance days on trimethoprim/sulfamethoxazole was 15.5 days and on the alternative drug was 16 days. The median proportion of neutropenic days per patient was 0.029 on trimethoprim/sulfamethoxazole and 0.022 on the alternative drug.
Conclusions: Intermittent dosing of trimethoprim/sulfamethoxazole on 2 consecutive days per week is an effective alternative prophylactic regimen for P. carinii pneumonia in pediatric patients with leukemia and lymphoma. This analysis does not support a difference in neutropenia during maintenance therapy between patients who are treated with trimethoprim/sulfamethoxazole versus an alternative drug.