Emergence of Imipenem-ResistantPseudomonas aeruginosaClinical Isolates from Egypt CoharboringVIMandIMPCarbapenemases

Abstract

Pseudomonas aeruginosa is an important human pathogen and the leading cause of nosocomial infections. P. aeruginosa is characterized by massive intrinsic resistance to a multiple classes of antibiotics with carbapenems being the most potent inhibitor of P. aeruginosa and considered the first choice for its treatment. Therefore, it is crucial to investigate novel mechanisms of resistance of P. aeruginosa to carbapenems for achieving successful therapy. A total of 114 P. aeruginosa isolates from two university hospitals in Egypt were recruited in this study. Antimicrobial susceptibility testing revealed that 50 isolates (43.8%) exhibited multidrug-resistant (MDR) phenotype, of them 14 isolates (12.2%) were imipenem (IPM)-resistant. Of these 14 isolates, 13 isolates (11.4%) exhibited the metallo-β-lactamase (MBL) phenotype. MBLs encoding genes, VIM and IMP, were identified by PCR. PCR results revealed that four isolates harbored the VIM gene alone, one isolate harbored IMP gene alone, and four isolates harbored both genes. The correct size of PCR products of VIM and IMP genes (390 and 188 bp, respectively) were sequenced to confirm results of PCR and to look for any possible polymorphism among MBL genes of tested isolates. Data analysis of these sequences showed 100% identity of nucleotide sequences of MBL genes among tested Egyptian patients. To our knowledge, this is the first report of IMP carbapenemase-encoding gene in Africa and the first detection of the emergence of P. aeruginosa coproducing VIM and IMP genes in Egypt.

Serotypes, Antibiogram and Genetic Relatedness of <i>Pseudomonas aeruginosa</i> Isolates from Urinary Tract Infections at Urology and Nephrology Center, Mansoura, Egypt

“…This was demonstrated in the present study as more than 50% of isolates were MDR. A nearby percent of MDR P. aeruginosa (43.8%) was reported by El-Domany et al [35] and a higher percent (64%) by Hashem et al [36]. Our isolates were associated with high resistance rate to piperacillin, cefoperazone/sulbactam, gentamicin and quinolones (48.7% -61.5%).…”

Detection of blaSPM-1 and blaSIM-2 Metallo-β-Lactamases Genes in Imipenem-Resistant Pseudomonas aeruginosa Clinical Isolates Recovered from Two University Hospitals in Egypt

“…Very recently, metallobeta-lactamases producing-Pseudomonas aeruginosa were isolated from hospitals in Minia, Egypt 40 . Furthermore, a recent work from our laboratory has shown the emergence of P. aeruginosa clinical isolates that coproduce blaVIM and blaIMP carbapenemases 41 . Moreover, we have recently reported the emergence of Imipenem-resistant Pseudomonas aeruginosa clinical isolates from Egypt that harbor blaGIM-1 gene 42 .…”

Prevalence of metallo-β-lactamase-encoding genes among carbapenem-resistant Pseudomonas aeruginosa strains isolated from burn patients in Iran

“…Pseudomonas aeruginosa is a major cause of life-threatening infections in burn patients worldwide 1,2 . It has a remarkable capacity to develop resistance to multiple classes of antimicrobial agents, and consequently, is considered a multidrug resistant (MDR) pathogen 3 . Carbapenems are considered first-line agents to treat severe cases of P. aeruginosa infections 4 .…”

“…MBL enzymes are also able to hydrolyze penicillin and cephalosporins 7 . Twelve different types of MBLs (VIM, IMP, SPM, GIM, NDM, DIM, AIM, SIM, KHM, SMB, TMB, and FIM) have been identified so far 3 . These genes are usually encoded by mobile genetic elements, such as plasmids, transposons, and integrons, that allow them to disseminate horizontally among Gram-negative bacteria, posing a global challenge for all countries 3,6 .…”

“…MBL-producing P. aeruginosa was originally discovered in 1991 in Japan. Since then, it has been described in different parts of the world 3,5,6,8 . The first MBL-positive strains of P. aeruginosa were described in an Iranian burn center in 2008 and are currently recognized as one of the crucial hospital-acquired infectious agents 5 .…”