Prevalence of Carbapenem-Resistant Enterobacteriaceae and the Genes Responsible for Carbapenemase Production in a Tertiary Care Hospital in South India

Abstract

Introduction: Carbapenem resistance in Gram-negative bacilli (GNB) is a major concern in the management of resistant infections. The mechanism of carbapenem resistance is most commonly mediated by carbapenemases. The five most common genes (NDM, KPC, VIM, OXA, and IMP) are responsible for carbapenemase production. Knowledge of these genes is important for the management of the disease. Objective: To estimate the prevalence of different genes responsible for carbapenemase production in GNB at a tertiary healthcare centre in South India. Method: In this retrospective study, samples were collected over 16 months. Carbapenem-resistant GNB underwent to Xpert Carba-R assay (Cepheid, Sunnyvale, California, USA) for the detection of five important genes responsible for carbapenemase production: NDM, KPC, VIM, OXA, and IMP. Results: Out of 184 carbapenem-resistant GNB, 20 samples were not included in this study. The rest of the 164 samples grew Klebsiella pneumoniae (152), Escherichia coli (10), and Enterobacter (2). OXA-48 and NDM were the most common genes responsible, with 137 (84.5%) and 95 (58.6%), respectively. Among them, 70 (43.2%) showed the presence of both genes, and 1 (0.6%) showed the presence of OXA-48, NDM, and VIM. Individually, 66 (40.7%) of OXA-48, 24 (14.8%) of NDM, and one (0.6%) of VIM. In this study, the authors did not find the presence of IMP or KPC genes. Conclusion: As a result of limited options and the higher cost of antibiotics for carbapenem-resistant infections, knowledge of these genes helps in the selection and rational use of antibiotics reduces the cost of management and will prevent mortality and morbidity from these infections.

Carbapenem resistance in West Africa: a systematic review

“…The average prevalence of CRB in West Africa was 4.6% (1902/41635), ranging from 1.6% to 18.6%. This average of 4.6% is low compared to the prevalence of CRB reported on the Indian subcontinent (18-31%) [116,117], Africa and the Middle East (5.7-26.9%) [118], and Saudi Arabia 38-46% [119]. However, the prevalence of CRB reported in the USA was 4.5% [120].…”

Prevalence of Class 1 integron in disease-causing carbapenem-resistantEscherichia coliin a tertiary hospital in Kathmandu, Nepal

“…In this study KPC and IMP genes were not detected in any of the isolates, which is in agreement to the findings from a study in India on clinical CREc. 24 However, majority of the isolates (79.2%) were positive for NDM-1, followed by OXA-23, OXA-48, and VIM within the integron-positive population. The dominance of NDM-1 is not surprising, given that it is the most common carbapenemase gene that is found in E. coli [24][25][26][27] and; NDM-1 is particularly associated with class 1 integrons gene cassette and IncM plasmids which help them to mobilize.…”

“…24 However, majority of the isolates (79.2%) were positive for NDM-1, followed by OXA-23, OXA-48, and VIM within the integron-positive population. The dominance of NDM-1 is not surprising, given that it is the most common carbapenemase gene that is found in E. coli [24][25][26][27] and; NDM-1 is particularly associated with class 1 integrons gene cassette and IncM plasmids which help them to mobilize. 34 So the co-occurrence on NDM-1 with intI1 as well as with other OXA variants is concerning as they can transfer the antibiotic resistant trait by moving between species.…”

“…In this study, the prevalence of the Class-1 integron gene, intI1, among CREc isolates was found be high -92% (n=48/52). Though not similar, a varying prevalence percentage of class 1 integrons has been well documented within multidrug-resistant E. coli from humans, 10,[23][24][25][26][27][28][29] animals, [29][30] and the environment. 7,[13][14][15] One possible reason for such high prevalence may be that integrons occur widely in Enterobacteriaceae family, and are strongly correlated with MDR.…”