Twice Weekly Pneumocystis jiroveci Pneumonia Prophylaxis With Trimethoprim-Sulfamethoxazole in Pediatric Patients With Acute Lymphoblastic Leukemia

Background: Pneumocystis jiroveci pneumonia (PCP) prophylaxis has become the standard of care for immunocompromised patients secondary to human immunodeficiency virus, chemotherapy, or prolonged steroid usage. The current recommendations for PCP prophylaxis are for trimethoprim-sulfamethoxazole (TMP/SMX) therapy on 3 consecutive days per week. Our hospital has been using twice weekly TMP/SMX for our pediatric patients with acute lymphoblastic leukemia (ALL) for a number of years. Methods: We performed a retrospective review of all our pediatric ALL patients from November 1998 to November 2003. We looked specifically for chest radiograph findings, pathologic reports, bronchoalveolar lavages, or discharge diagnoses by the International Classification of Diseases, 9th revision code consistent with PCP. Those cases suspicious for PCP infection had their medical records reviewed in detail. Results: Eighty-seven patients were treated with TMP/SMX prophylaxis during the study period for a total of 56,483 patient days with no proven cases of PCP. These results are similar to studies of either daily or thrice weekly TMP/SMX prophylaxis for pediatric ALL patients, and more recent studies also using twice weekly TMP/SMX prophylaxis. Conclusions: Twice weekly TMP/SMX seems to be a reasonable alternative for PCP prophylaxis for pediatric ALL patients. In review of other recent publications on pediatric patients, this recommendation can likely be extended to other pediatric malignancies as well. Further study is required to determine the appropriate length of prophylaxis and whether once weekly TMP/SMX prophylaxis or SMX alone at current or smaller doses could provide effective prophylaxis.