Outcomes of Short Antibiotic Courses for Gram‐Negative Bloodstream Infections in Solid Organ Transplant Recipients—A Systematic Review and Meta‐Analysis

BACKGROUND: Gram-negative bloodstream infections (GN-BSIs) contribute significantly to morbidity and mortality. Optimizing antibiotic duration is critical, particularly in immunocompromised populations, but data for solid organ transplant (SOT) recipients remain limited. OBJECTIVE: To examine the effectiveness of short versus long antibiotic courses for GN-BSIs in SOT recipients. METHODS: This systematic review followed PRISMA guidelines (PROSPERO CRD42024620638). We searched four databases through June 2025 for randomized controlled trials (RCTs) and observational studies reporting outcomes in SOT recipients. Risk of bias was assessed, and random-effects meta-analyses were conducted. Primary outcome was 90-day mortality; secondary outcomes included clinical failure. RESULTS: Seven studies (2 RCTs, 5 cohorts) involving 249 SOT patients were analyzed. In RCTs, 90-day mortality (RD: -0.07; 95% CI: -0.18 to 0.05; p = 0.25) and clinical failure (RR: 0.62; 95% CI: 0.18-2.15; p = 0.45) were lower in the short-course group. In cohort studies, 90-day mortality (RR: 0.36; 95% CI: 0.06-2.08; p = 0.25) was also lower, but clinical failure (RR: 1.89; 95% CI: 0.81-4.43; p = 0.14) was higher in the short-course group. None of the differences were statistically significant. Certainty of evidence was moderate in RCTs, and very low in the cohort studies. CONCLUSION: Our review underscores the importance of including SOT recipients in trials comparing short versus long antibiotic therapy for GN-BSIs. Although no statistically significant differences were observed between treatment durations, the limited sample size precludes definitive conclusions and highlights the need for larger, high-quality studies.