Antibiotic treatment durations for pyogenic liver abscesses: A systematic review

Background: We sought to systematically review the existing research on pyogenic liver abscesses to determine what data exist on antibiotic treatment durations. Methods: We conducted a systematic review and meta-analysis of contemporary medical literature from 2000 to 2020, searching for studies of pyogenic liver abscesses. The primary outcome of interest was mean antibiotic treatment duration, which we pooled by random-effects meta-analysis. Meta-regression was performed to examine characteristics influencing antibiotic durations. Results: Sixteen studies (of 3,933 patients) provided sufficient data on antibiotic durations for pooling in meta-analysis. Mean antibiotic durations were highly variable across studies, from 8.4±5.3 to 68.9±30.3 days. The pooled mean treatment duration was 32.7 days (95% CI 24.9 to 40.6 days), but heterogeneity was very high ( I 2 = 100%). In meta-regression, there was a non-significant trend towards decreased mean antibiotic treatment durations over later study years (−1.14 days/study year, 95% CI −2.74, +0.45, p = 0.16). Mean treatment duration was not associated with mean age of participants, percentage of infections caused by Klebsiella spp., percentage of patients with abscesses over 5 cm in diameter, percentage of patients with multiple abscesses, and percentage of patients receiving medical management. No randomized trials have compared treatment durations for pyogenic liver abscess, and no observational studies have reported outcomes according to treatment duration. Conclusions: Among studies reporting on antibiotic durations for pyogenic liver abscess, treatment practices are highly variable. This variability does not seem to be explained by differences in patient, pathogen, abscess, or management characteristics. Future RCTs are needed to guide optimal treatment duration for patients with this complex infection.