Prophylaxis for Pneumocystis pneumonia (PCP) in non-HIV immunocompromised patients

Abstract

Background: Pneumocystis pneumonia (PCP) is a disease affecting immunocompromised patients. PCP among these patients is associated with significant morbidity and mortality.

Objectives: To assess the effectiveness of PCP prophylaxis among non-HIV immunocompromised patients. To define the type of immunocompromised patients for whom evidence suggests a benefit for PCP prophylaxis.

Search strategy: Electronic searches of The Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library Issue 1, 2007), PubMed (March 2007), LILACS (March 2007), relevant conference proceedings; references of identified trials; the first author of each included trial was contacted.

Selection criteria: RCTs or quasi- RCTs comparing prophylaxis with an antibiotic effective against Pneumocystis versus placebo, no intervention, an antibiotic/s with no activity against Pneumocystis or another antibiotic effective against Pneumocystis for immune-compromised non-HIV patients. Only trials pre-defining Pneumocystis infections as an outcome were included.

Data collection and analysis: Two authors independently appraised the quality of each trial and extracted data from included trials. Relative risks (RR), with 95% confidence intervals (CI) were estimated and pooled using the random effects model.

Main results: Eleven trials including 1155 patients (520 children), performed between the years 1974 and 1997, were included. Compared to no treatment or treatment with fluoroquinolones (inactive against Pneumocystis), there was a 91% reduction in the occurrence of PCP in patients receiving prophylaxis with trimethoprim/sulfamethoxazole, RR 0.09 (95% CI 0.02 to 0.32), eight trials, 821 patients. No significant difference was encountered in all cause mortality, RR 0.81 (95% CI 0.27 to 2.37), five trials, 509 patients, while PCP-related mortality was significantly reduced, RR 0.17 (95% CI 0.03 to 0.94), seven trials, 701 patients. Occurrence of leukopenia, neutropenia and their duration were not reported consistently. No significant difference in any adverse event was seen comparing trimethoprim/sulfamethoxazole to no treatment/ placebo (four trials, 470 patients). No differences between once daily versus thrice weekly trimethoprim/sulfamethoxazole were seen (two trials, 207 patients).

Authors' conclusions: Given an event rate of 7.5% as in included trials' control group, prophylaxis for PCP using TMP/SMX is highly effective among non-HIV patients, with a number needed to treat of 15 patients (95% CI 13 to 20). Prophylaxis should be considered for the types of patients with hematological malignancies, bone marrow transplantation and solid organ transplantation included in these trials.