Single-day trimethoprim/sulfamethoxazole prophylaxis for Pneumocystis pneumonia in children with cancer.

OBJECTIVE: To determine whether a simplified, 1-day/week regimen of trimethoprim/sulfamethoxazole is sufficient to prevent Pneumocystis (jirovecii [carinii]) pneumonia (PCP). Current recommended regimens for prophylaxis against PCP range from daily administration to 3 consecutive days per week dosing. STUDY DESIGN: A prospective survey of the regimens adopted for the PCP prophylaxis in all patients treated for childhood cancer at pediatric hematology-oncology centers of the Associazione Italiana Ematologia Oncologia Pediatrica. RESULTS: The 20 centers participating in the study reported a total of 2466 patients, including 1093 with solid tumor and 1373 with leukemia/lymphoma (or primary immunodeficiency; n = 2). Of these patients, 1371 (55.6%) received the 3-day/week prophylaxis regimen, 406 (16.5%) received the 2-day/week regimen, and 689 (27.9%), including 439 with leukemia/lymphoma, received the 1-day/week regimen. Overall, only 2 cases of PCP (0.08%) were reported, both in the 2-day/week group. By intention to treat, the cumulative incidence of PCP at 3 years was 0.09% overall (95% CI, 0.00-0.40%) and 0.51% for the 2-day/week group (95% CI, 0.10%-2.00%). Remarkably, both patients who failed had withdrawn from prophylaxis. CONCLUSION: A single-day course of prophylaxis with trimethoprim/sulfamethoxazole may be sufficient to prevent PCP in children with cancer undergoing intensive chemotherapy regimens. This simplified strategy might have implications for the emerging need for PCP prophylaxis in other patients subjected to the increased use of biological and nonbiological agents that induce higher levels of immune suppression, such as those with rheumatic diseases.

A prospective study on the efficacy of mobilization of autologous peripheral stem cells in pediatric oncohematology patients.

BACKGROUND: Peripheral blood stem cells (PBSCs) are the preferred source in autologous transplantation. We assessed prospectively the efficacy of mobilization in pediatric patients and risk factors associated with its failure. STUDY DESIGN AND METHODS: Patients, aged 0 to 17 years, needing a first collection of PBSCs for autologous stem cell transplantation were eligible. The study period was from July 2008 to September 2010. A blood peak of fewer than 20 × 10(6) CD34+ cells/L was used as the cutoff to define a poor mobilizer. RESULTS: A total of 145 patients, 57% male (82) and 43% female (63), with a median age of 7 years, affected by solid tumor, 79% (114), and acute leukemia or lymphoma, 21% (31), were enrolled. Granulocyte-colony-stimulating factor used was filgrastim in 69%, lenograstim in 26%, and pegfilgrastim in 5% of patients. A total of 83% (121) of patients mobilized successfully, the median CD34+ count being 120 × 10(6) /L (range, 23 × 10(6) -1840 × 10(6) /L). A single leukapheresis procedure was sufficient to achieve the target CD34+ cell dose in 82% (99/121) of patients. Among 24 poor mobilizer patients, 15 underwent a second mobilizing course and nine required a marrow harvest. Factors associated with poor mobilization were metastatic disease and relapse. Among 99 patients who underwent autologous stem cell transplantation, the median times to neutrophil and platelet engraftment and of hospitalization were longer by 2, 12, and 6 days in poor versus good mobilizer group. CONCLUSIONS: In pediatric patients undergoing a first mobilization, the incidence of poor mobilization was 17%. Failure of mobilization resulted in an increase in health costs and a longer hospitalization for those who underwent autologous stem cell transplantation.