Detection of Antibiotic Resistance Determinants and Their Transmissibility among Clinically Isolated Carbapenem-Resistant <b><i>Escherichia coli</i></b> from South India

Abstract

Objectives: The aim of this study was to analyze the prevalence of the CTX-M, TEM, SHV, VIM, NDM, and OXA genes in carbapenemase-producing Escherichia coli and their transmissibility at a tertiary care hospital in south India. Materials and Methods: Twenty-one carbapenem-resistant E. coli (carbapenem-resistant Enterobacteriaceae; CRE) were collected from the Sri Sathya Sai Institute of Higher Medical Sciences (Puttaparthi India). Resistance to antibiotics was analyzed by Vitek-2, and the identity of the isolates was confirmed by 16S rDNA sequencing. RAPD and enterobacterial repetitive intergenic consensus (ERIC)-PCR were performed for molecular typing. Metallo-β-lactamase production was confirmed by a double disc synergy test. The presence of the extended-spectrum β-lactamases CTX-M, TEM, and SHV and of the carbapenemases NDM, VIM, and OXA was determined by PCR. Carbapenemase variants were further confirmed by sequencing. The transmissibility of the genes was tested by conjugation. Results: Twelve of the 21 (57%) carbapenem-resistant E. coli isolates were community acquired, indicating the spread of CRE in environmental samples. TEM and NDM-5 were found to be the major β-lactamases produced by the pathogens. OXA-181 was found in 5 of the isolates. All 21 isolates were found to harbor more than one of the tested β-lactamases, and all of the isolates were found to have the capacity to participate in conjugation; 15 of the transconjugants were found to have acquired the tested β-lactamases, substantiating their ability to be transferred to other strains of bacteria. Conclusion: Monitoring of community-acquired carbapenem-resistant bacteria is very important as the association of resistance determinants with mobile genetic elements would present a serious clinical challenge.

Molecular Analyses of Biofilm-Producing Clinical <b><i>Acinetobacter baumannii</i></b> Isolates from a South Indian Tertiary Care Hospital

“…We found that bla TEM is the most prevalent ESBL among A. baumannii isolates, although previous reports have indicated that bla CTX-M is the pre-dominant ESBL gene [19,20]. Similar findings were observed in our previous report on carbapenem-resistant Enterobacteriaceae [8]. This study suggests that bla SHV is not a commonly encountered ESBL gene among A. baumannii strains on the Indian subcontinent.…”

“…Genomic analysis of MDR A. baumannii has indicated the presence of integrons, transposons, and other mobile genetic elements (MGEs) such as A. baumannii antibiotic resistance (AbaR) islands. Acquisition of these resistance determinants has been attributed to the potential for horizontal gene transfer among A. baumannii isolates [7, 8]. The ATPase-encoding gene comM (competence protein) is split by the incoming AbaR island, leading to the formation of 2 segments, i.e., comM -AbaR and AbaR- comM [9].…”

The Global Ascendency of OXA-48-Type Carbapenemases

“…Currently, Enterobacterales with bla OXA-181 are endemic in the Indian subcontinent (e.g., India, Pakistan, Bangladesh, and Sri Lanka) and are important causes of nosocomial outbreaks in India (175,176) and Bangladesh (177). Nosocomial outbreaks have also been described in Angola (167), South Africa (178), São Tomé and Príncipe (170), and the United Arab Emirates (179) (Fig.…”

Characterization of antibiotic-resistant Escherichia coli associated with urinary tract infections in Southern Colombia

“…In contrast, Hoang et al [22] isolated strains of E. coli from healthy adults in Vietnam and noted the marked presence of blaCTX-M genes (blaCTX-M-9 and blaCTX-M-1), followed by blaTEM genes. Mahalingam et al [17] analyzed the prevalence and transmissibility of the blaCTX-M, blaTEM, blaSHV, VIM, NDM, and OXA genes in Universitas Scientiarum Vol. 25 (3): 463-488 http://ciencias.javeriana.edu.co/investigacion/universitas-scientiarum carbapenemase-producing E. coli in a tertiary care hospital in Southern India.…”