Distribution of blaCTX − M, blaTEM, blaSHV and blaOXA genes in Extended-spectrum-β-lactamase-producing Clinical isolates: A three-year multi-center study from Lahore, Pakistan

Antimicrobial Resistance & Infection Control

Samyyia Abrar¹  Noor Ul Ain¹  Huma Liaqat¹  Shahida Hussain¹  Saba Riaz²  Farhan Rasheed³ 

[1] 0000 0001 0670 519X, grid.11173.35, Department of Microbiology and Molecular genetics, University of the Punjab, Lahore, Pakistan;0000 0001 0670 519X, grid.11173.35, Department of Microbiology and Molecular genetics, University of the Punjab, Lahore, Pakistan;Citilab and Research Center, Lahore, Pakistan;Allama Iqbal Medical College, Jinnah Hospital Lahore, Lahore, Pakistan;

关键词: AST;    Multiplex PCR;    ESBL;    Phenotypic test;    Molecular tests;    Pakistan;   

DOI  :  10.1186/s13756-019-0536-0

来源: publisher

【 摘 要 】

BackgroundFrequency of extended-spectrum-β-lactamase-producing clinical isolates is increasing worldwide. This is a multi-center study which was aimed to check the frequency of third-generation cephalosporin resistance and distribution of the key genetic determinants of Extended-spectrum-β-lactamase-producing Clinical isolates in Pakistan.MethodsA total of 2372 samples were processed in three tertiary care hospitals and one diagnostic research center of Lahore, Pakistan during Aug-2014 to Sep-2017. Analytical profile index (API 20-E) was used for biochemical characterization of isolates. Antibiotic susceptibility testing (AST) and third generation cephalosporin resistant (3GC-R) isolates were subjected to: double disc synergism test (DDST), combination disc test (CDST) and epsilometric test (E-test) for confirmation of ESBL-production. PCR amplification of isolates with plasmid and genomic DNA was performed. Amplicon sequences were checked for gene-variants and statistical analyses were performed to check the significance of data.ResultsA total of 497/995 (50%) isolates including Escherichia coli 65% (n = 321), Klebsiella spp. 25% (n = 124) and Pseudomonas. 5% (n = 24), Enterobacter spp. 4% (n = 20) and Acinetobacter spp. 2% (n = 8) were screened as third generation cephalosporin resistant (3GC-R). Urine 56% (n = 278) followed by pus 20% (n = 99) and wound swab 6% (n = 29) were frequent sources. Incidence of ESBL-producers detected by combination disc test was 79% (n = 392). PCR revealed blaCTX − M (76%) gene followed by blaOXA (52%), blaTEM (28%) and blaSHV (21%) were most prevalent among ESBL-producers detected by CDST. blaCTX − M − 1(65%), blaOXA (78%) and blaTEM (57%) genes were carried on plasmids. Amplicon sequencing revealed blaCTX − M − 15 (75%), blaOXA − 1 (49%) and blaTEM − 1B (34%) and 21 (n = 28) isolates carried three genes in them.ConclusionPrevalence of ESBL-producing isolates has increased 1.13 folds during study years. Isolates had high prevalence of ESBL-encoding blaCTXM − 15 gene and narrow spectrum blaOXA − 1 and blaTEM − 1B were also prevalent.

【 授权许可】

CC BY