Frequency of Carbapenemase Genes in Acinetobacter baumannii complex Isolates from Burn Wounds in Motahari Hospital, Tehran, Iran

Aims: Acinetobacter baumannii complex (Acb complex) are opportunistic Gram-negative bacteria responsible for a diverse array of nosocomial infections. In recent years, carbapenem-resistant Acb complex has become a global concern. Carbapenemases are one of the most important mechanisms of resistance to carbapenems. This study aimed to measure the prevalence of carbapenemase genes in Acb complex isolates from burn wounds in a burn center in Iran. Materials & Methods: During six months, ۵۰ Acb complex isolates were collected from the wounds of burn patients admitted to Motahari hospital in Tehran (۲۰۲۰-۲۰۲۱). Antimicrobial susceptibility testing was performed for the isolates using Kirby-Bauer disc diffusion method based on the Clinical and Laboratory Standards Institute ۲۰۲۰ guidelines. DNA extraction was done by boiling method. The existence of blaOXA-۵۱, blaOXA-۲۳, blaIMP, blaNDM-۱, and blaKPC genes was evaluated by PCR and gel electrophoresis. Findings: All isolated bacteria were confirmed as Acb complex based on positive PCR results for the presence of the blaOXA-۵۱ gene. According to the antibiotic susceptibility testing results, the isolates showed ۱۰۰% resistance to ceftazidime, ۹۸% to ciprofloxacin, amikacin, and imipenem, and ۹۴% to gentamicin and piperacillin-tazobactam. The most prevalent carbapenemase genes among the isolates were blaOXA-۵۱ and blaOXA-۲۳ (۱۰۰%), followed by blaIMP (۲۶%), blaNDM-۱ (۱۴%), and blaKPC (۴%). Conclusion: Carbapenem resistance and the prevalence of carbapenemase genes among Acb complex isolates has reached an alarming rate. Collaborative global efforts are crucial to safeguard antibiotic effectiveness and enhance patient care amidst escalating antimicrobial resistance challenges.

کلیدواژه ها:

Acinetobacter baumannii ، Drug resistance ، Carbapenems ، Carbapenemase