Investigation of Antimicrobial Effect of Berberine on Ciprofloxacin and Imipenem Resistance Acinetobacter baumannii Isolated from Hamadan Hospitals

Background: Acinetobacter baumannii is one of the causes of nosocomial infections, especially in the intensive care unit. The emergence of multidrug-resistant strains of A. baumannii has caused many problems. One of the ways to handle the phenomenon of antibiotic resistance is the use of herbal medicines and their derivatives in place of or in combination with antibiotics. The aim of this study was to investigate the effect of inhibitory effects of berberine as a barberry derivative on clinical isolates of A. baumannii, resistant to ciprofloxacin and imipenem in Hamadan hospitals. Materials and Methods: In this study, 70 clinical isolates of A. baumannii. were identified and diagnosed using conventional microbiology. Resistance of isolates was detected against imipenem and ciprofloxacin by disk diffusion and broth microdilution method. Minimum inhibitory concentration (MIC) of berberine as well as its combined effect with antibiotics were performed using broth microdilution method. Results: The results of this study showed that more than 90% of isolates are resistant to ciprofloxacin and imipenem. Imipenem and ciprofloxacin MICs  were dtermined from 8 to 28  and 4 to 32 μg / mL, respectively. The berberine decreased the imipenem and ciprofloxacin MIC from zero to two fold and zero to one-fold, respectively Conclusion: High level resistance to imipenem and ciprofloxacin among A.baumannii isolates is cause of concern. Berberin, in combination with imipenem and ciprofloxacin, reduces MIC to a proper level, which can be used as an effective agent to reduce antibiotic resistance in bacteria.