A comprehensive meta-analysis of antibiotic resistance pattern among biofilm production strains of Acinetobacter baumannii recovered from clinical specimens of patients

Acinetobacter baumannii can persist and circulate in the hospital environment due to multiple resistance mechanisms including biofilm formation. This study aimed to determine the pattern of antibiotic resistance, the biofilm formation rate, and the correlation between biofilm production and antibiotic resistance. We performed a comprehensive search in different international and Iranian databases according to PRISMA protocol. We searched for English studies addressing drug resistance and biofilm formation from January 2000 to 31th December 2019. The Mesh terms used were; “A. baumanii” OR “Acinetobacter baumannii” AND “Multidrug resistance” OR “MDR” AND “antimicrobial drug resistance” OR “Antibiotic resistance” AND “biofilm formation” OR “Biofilms” AND “clinical samples” AND “hospital settings” AND “prevalence” AND “patients” AND “Iran”. The search process was done by two researchers independently. Data analyzed using CMA software. The combined Biofilm formation rate was 69.1% (95% CI 53.9–81). 39.1%, 31.5%, and 38.5% of strains had weak, moderate, and strong-adherence activity, respectively. The pooled prevalence of MDR isolates was 96.1%. The highest combined antibiotic resistance was against to Ceftazidime (95.5%). The least resistance was against colistin, followed by Tigecycline with frequencies of 4.1% and 5.7%, respectively. Four out of 11 studies showed a significant correlation between biofilm formation and antibiotic resistance. Our study reported a high combined biofilm formation rate. So, this research can help control and implement appropriate strategies against infections mediated by MDR A. baumannii strains. Also, our findings showed that effective antibiotics were colistin and Tigecycline against infections caused by A. baumannii. •The combined Biofilm formation rate was 69.1% (95% CI 53.9–81). 39.1%, 31.5%,•38.5% of strains had weak, moderate, and strong-adherence activity, respectively.•The pooled prevalence of MDR isolates was 96.1%.