Before the use of trimethoprim-sulfamethoxazole prophylaxis, up to 43% of children with cancer developed Pneumocystis jirovecii pneumonia (PCP). Current recommendations for prophylaxis vary considerably, from daily dosing to thrice weekly dosing. A multi-centre Italian prospective survey compared treatment regimens in 2466 children with newly diagnosed cancer from 2009 to 2011, including 1093 with solid tumours and 1373 with leukaemia/lymphoma. Of these patients, 1371 received the 3-day/week prophylaxis regimen, 406 received the 2-day/week regimen, and 689 received the 1-day/week regimen (5–10 mg/kg/day in two doses). Only two cases of PCP (0.08%) were reported, both in the 2-day/week group, and both had ceased prophylaxis. The authors concluded that a one-day-per-week regimen of trimethoprim/sulfamethoxazole may be sufficient to prevent PCP in immunosuppressed children with cancer. Take home message: One-day-per-week trimethoprim-sulfamethoxazole dosing for PCP prophylaxis appears sufficient to prevent PCP in immunosuppressed children with cancer, is simpler than twice or thrice weekly dosing, and may improve adherence. This regimen merits consideration in children with cancer and potentially in children at risk of PCP from primary immunodeficiency, transplantation or other medical immunosuppression.
Reviewer: Brendan McMullan, Sydney Children's Hospital, Randwick (firstname.lastname@example.org)