High incidence of MBL-mediated imipenem resistance among Pseudomonas aeruginosa from surgical site infections in Egypt

Abstract

Introduction: Surgical wound infection is a serious problem, especially with metallo-beta lactamases (MBLs)- producing gram-negative bacteria as Pseudomonas aeruginosa. The main objective of this work was to evaluate for the first time in Minia- Upper Egypt, the incidence of imipenem-resistant Pseudomonas aeruginosa infection of surgical wounds particularly that mediated by MBL production.

Methodology: P. aeruginosa was isolated from infected wounds by swabs and underwent full microbiological identification and Antibiotic Susceptibility testing. MBL production was tested by E-test and PCR was used for imipenemase (bla_IMP) and Verona integron-encoded metallo-beta-lactamase (bla_VIM) gene detection.

Results: Out of 200 pus samples collected from surgical site infections, P. aeruginosa had the prevalence rate of 35%. Imipenem resistance was found in 28.57% of the isolated Pseudomonas aeruginosa. The prevalence of MBL-producing isolates among Imipenem-resistant P. aeruginosa (IRPA) was 85 % by phenotypic method with 29% of them harboring bla_VIM gene. High resistance rates to other classes of antibiotics were reported among the isolates with multi-drug resistance (MDR) detected in 97.3% of the isolates.

Conclusion: To our knowledge, this is the first report in Minia, Upper Egypt describing the relatively high incidence of IRPA in infected surgical wounds with MBLs involved in the majority of isolates.