Quinolone prophylaxis during neutropenia in hematopoietic stem cell transplant (HSCT) recipients has been shown to be effective in preventing bloodstream infections (BSI). However, an increase in the incidence of multidrug-resistant bacteria has been observed, leading some centers to discontinue prophylaxis. The aim of this study was to analyze the literature on the impact of suspending quinolone prophylaxis in adult HSCT recipients through a systematic review and meta-analysis. Searches were performed in MedLine, Embase, SCOPUS, LILACS and Web of Science databases up to May 20, 2025. Two independent reviewers screened articles and extracted data. Studies were included if they: reported clinical characteristics of adult HSCT recipients; presented outcomes (BSI and mortality); and were available in full text. Meta-analysis was conducted using a random-effects model, calculating pooled risk ratios (RR) and 95% confidence intervals (95% CI) for outcomes. A total of 1,438 studies met the selection criteria and 13 were included. Most were conducted in Asia (46.1%). All were observational and single-center, with the majority being quasi-experimental (76.9%). Study duration ranged from 29 to 120 months, and the period without prophylaxis ranged from 12 to 68 months. Overall, 3,986 HSCT recipients were included, most of them allogeneic (n = 2,192; 54.9%) and male (n = 2,095; 51.5%). The mean age ranged from 41.2 ± 8.5 to 59.0 ± 10.3 years. A total of 2,131 patients (53.4%) were evaluated during the period with prophylaxis and 1,855 (46.5%) in the absence of prophylaxis. Prophylaxis was associated with a lower risk of BSI due to any microorganism (RR: 0.68; 95% CI: 0.55–0.85; p = 0.0007; I² = 60%) and due to Gram-negative bacteria (RR: 0.54; 95% CI: 0.38–0.75; p = 0.0003; I² = 67%). On the other hand, it was associated with a higher risk of BSI due to quinolone-resistant bacteria (RR: 2.42; 95% CI: 1.34–4.38; p = 0.003; I² = 67%) and carbapenem-resistant Gram-negative bacteria (RR: 6.19; 95% CI: 2.69–14.25; p < 0.0001; I² = 46%). Discontinuation of prophylaxis was not associated with increased mortality (RR: 1.17; 95% CI: 0.89–1.55; p = 0.27; I² = 38%). Discontinuation of quinolone prophylaxis in HSCT recipients was associated with an increased incidence of BSI, but not with a higher risk of death. In addition, a significant improvement in antimicrobial resistance profiles was observed.
Randi et al. (2026) studied this question.