Phenotypic Detection of ESBL, MBL (IMP-1), and AmpC Enzymes, and Their Coexistence in Enterobacter and Klebsiella Species Isolated From Clinical Specimens

Abstract

Background: Bacterial resistance to beta-lactam is a major problem in all developed and developing countries. The genera of Klebsiella and Enterobacter are associated with opportunistic and nosocomial infections. All beta-lactamase genes can cause dissemination of resistance to beta-lactams. Objectives: The present study aimed to investigate the phenotypic detection of beta-lactamases in Enterobacter and Klebsiella species isolated from clinical specimens. Materials and Methods:This cross-sectional study was performed on 59 Klebsiella spp. and 49 Enterobacter spp. isolated from clinical samples. They were confirmed using API 20E. These bacteria were evaluated for the production of extended-spectrum beta lactamase (ESBL), metallo-beta-lactamase (MBL) (IMP-1), and the pAmpC and iAmpC enzymes. This was done using the Clinical and Laboratory Standards Institute (CLSI) method, 2-mercaptopropionic acid, the cefoxitin method, and the use of imipenem as an enzyme inducer, respectively. Mask-ESBL production was also identified, using different concentrations of 3-amino-phenyl boronic acid compound. Data were analyzed with SPSS version 22. Results: In total, 38 (64.4%) Klebsiella spp. and 41 (83.7%) Enterobacter spp. produced at least one type of beta-lactamase. AmpCproducing Enterobacter spp. (71.4%), and ESBL-producing Klebsiella spp. (42.4%) had the highest prevalence of beta-lactamase types in each genus. There were two bacteria in both types that were resistant to all antibiotics without producing any type of beta-lactamase. Conclusions: According to our findings, it is necessary to pay special attention to ESBL production in Klebsiella spp., while in Enterobacter spp., it is essential to search for AmpC production (chromosomal and plasmid). In addition, the genotypic evaluation of beta-lactamase variety in these bacteria may be necessary in different geographical areas.

Phenotypic Detection of Beta-lactamases among Proteus mirabilis, Enterobacter cloacae, and Citrobacter freundii Isolates from Urinary Samples in Gorgan, Northeast Iran

“…In China, out of 84 carbapenem-resistant E. cloacae isolates from three tertiary hospitals, 50 (59.5%) were MBL producers [19]. In agreement with our results, a study in North West Bank-Palestine reported 14.6% MBL and 11.1%AmpC β-lactamases among the E. cloacae isolates [20], but in Babol, north Iran, higher rates were reported for E. cloacae isolates from clinical specimens [21]. In India, out of 251 Gram-negative bacteria isolates from clinical specimens, 7 (2.7%) and 25 (9.9%) were Proteus spp.…”

Phenotypic Detection of Β-Lactam Antibiotics, Methicillin and Inducible Clindamycin Resistance Among Bacterial Isolates in Patients with Otitis Externa

“…C: Gram positive cocci Teicoplanin (TEC) (glycopeptides) Erythromycin (E) (Macrolide) Linezolid (LZD) (Oxazolidinones) GM, CIP, TS (19) Special diagnostic tests were performed for the identification of ESBL producers (double disk), mask ESBL (inhibiting methods with 3APBA) (2), pAmpC (FOX disc method) (21), iAmpC (using IMP as an inducer), and metallo beta lactamase (IMP-1 using 2-MPA method) (2).…”

“…According to Ambler classification, ExtendedSpectrum B-Lactamases (ESBLs) belong to class A and D. Also, class C and B are called AmpC enzymes (contain two types-plasmid-mediated AmpC or pAmpC and inducible AmpC or iAmpC-) and Metallo beta lactamase, respectively (2); high prevalence of A, B, and C classes of β-lactamase producers have been reported in Enterobacteriaceae (3).…”

Multi-drug Resistance, β-Lactamases Production, and Coexistence of blaNDM-1 and mcr-1 in Escherichia coli Clinical Isolates From a Referral Hospital in Kathmandu, Nepal

“…The ZOI with the increase in 5 mm around the disk containing boronic acid and cefoxitin in comparison with the diameter around the disk of cefoxitin alone, was regarded as an AmpC producer. 26 …”