Prevalence and Antibiotic Resistance of Biofilm-Forming Clinical Escherichia coli Isolates in Asia: A Systematic Review and Meta-Analysis

Biofilm formation in Escherichia coli promotes persistence, pathogenicity, and antibiotic resistance in the infections of urinary tract, bloodstream, and wounds, highlighting a global public health concern. This systematic review and meta-analysis evaluated the prevalence and antibiotic resistance patterns of biofilm-forming clinical E. coli isolates from 17 Asian countries. Following PRISMA guidelines, PubMed and Google Scholar were searched for studies spanning January 2010 and May 2025, and 67 studies were included. In a random-effects meta-analysis of 31 microtiter plate studies (logit-transformed proportions, DerSimonian–Laird τ2, Hartung–Knapp–Sidik–Jonkman confidence interval), the pooled biofilm prevalence was 63% (95% CI: 51–73%; 95% prediction interval [PI]: 17–93%; I2 = 95.6%, p < 0.0001). Pooled estimates were similar across the detection methods (63–67%). Urinary isolates, which dominated the dataset, had a pooled prevalence of 65% (95% CI: 51–77). Among the biofilm-producing isolates (microtiter plate assay), separately pooled proportions of strong, moderate and weak producers were 26%, 35% and 35%, respectively; non-producers accounted for 35% of all isolates tested (k = 40, any detection method). Among the biofilm producers, pooled resistance proportions were highest for ampicillin (84%) and amoxicillin–clavulanate (78%), and lowest for ertapenem (8%) and meropenem (18%); descriptive class-level means were highest for tetracyclines (66.4%) and fluoroquinolones (60.4%). These in vitro susceptibility data may not establish clinical effectiveness against biofilm-associated E. coli infections. Funnel-plot asymmetry was detected for four subgroups (Egger’s/Begg’s test, p < 0.10), and trim-and-fill sensitivity analyses shifted the estimates to inconsistent directions (e.g., total microtiter 50% [37–63%]; urine isolates 53% [37–68%]), consistent with small-study effects and heterogeneity rather than publication bias alone. Overall, the published evidence indicates that biofilm formation and resistance against common antibiotics are frequently reported among clinical E. coli isolates in Asia, particularly urinary isolates. However, the high heterogeneity and wide prediction interval indicate that prevalence in individual settings may differ substantially from the pooled estimate; thus, standardized multicenter surveillance is needed to inform catheter care and antibiotic stewardship for E. coli infections across Asia.