Susceptibility to antimicrobials of Acinetobacter baumannii and Pseudomonas aeruginosa clinical strains and their blaVIM variants in ICU of Regional Burn Centre

Abstract

SUMMARY Aim: To study in clinical strains of Acinetobacter baumannii and Pseudomonas aeruginosa, as dominating in ICU of Regional Centre of Thermal Injury, their susceptibility to antibiotics, antiseptics and the incidence of blaVIM variants among them. Materials and methods: Clinical strains of A. baumannii and P. aeruginosa were collected from 126 patients with burns wounds in the early three days after injury in the period from February 2022 to August 2022. There was determined susceptibility of the 83 A.baumannii and 43 P.aeruginosa clinical strains to antibiotics was using disc-diffusion method, and to antiseptics – by means of double serial dilutions method. Among the isolated clinical strains with phenotypic resistance to carbapenems (double-disk diffusion test with meropenem and imipenem). The molecular identification of VIM genes was performed by polymerase chain reaction (PCR). Results: The lowest sensitivity of acinetobacteria was found to ceftazidime (4,82%), cefepime (4,82%), piperacillin-tazobactam (34,94%), meropenem (15,66%), imipenem (27,71%), levofloxacin (3,61%), ciprofloxacin and gatifloxacin (4,82%), moxifloxacin (9,38%), ofloxacin (12,5%). Received data demonstrated the highest resistance of P.aeruginosa to beta-lactam antibiotics, including carbapenems (imipenem 46,51%, meropenem 53,49%). Among clinical strains of Gram-negative bacteria with phenotypic resistance to carbapenems, the presence of the VIM gene in A.baumannii (n = 11; 13,3%), P.aeruginosa (n = 14; 33,3%) was found by PCR. The research has shown high sensitivity of A.baumannii to decamethoxine, octenidine; and high resistance to antiseptics of P.aeruginosa. Conclusions: Among isolates from patients in burn ICU with perioperative infectious complications A. baumannii and P.aeruginosa strains, which have low sensitivity to aminoglycosides, fluoroquinolones, inhibitor-protected piperacillin, cephalosporins, as well as phenotypic resistance to carbapenems imipenem and meropenem there is high risk of variants with blaVIM genes. However, their high susceptibility to detergents remain great importance of antiseptics in the prevention of infection in burn patients.