AUTHOR=Perez-Lopez Andres , Sundararaju Sathyavathi , Al-Mana Hassan , Tsui Kin Ming , Hasan Mohammad Rubayet , Suleiman Mohammed , Janahi Mohammed , Al Maslamani Eman , Tang Patrick 

TITLE=Molecular Characterization of Extended-Spectrum β-Lactamase–Producing Escherichia coli and Klebsiella pneumoniae Among the Pediatric Population in Qatar

JOURNAL=Frontiers in Microbiology

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2020.581711

DOI=10.3389/fmicb.2020.581711

ISSN=1664-302X

ABSTRACT=<sec><title>Introduction</title><p>Although extended-spectrum β-lactamase (ESBL)–producing Enterobacterales are a public health problem in the Arabian Peninsula, data on the molecular characteristic of their antimicrobial resistance determinants in children is limited.</p></sec><sec><title>Aim</title><p>To determine the molecular characteristics of ESBL-producing <italic>Escherichia coli</italic> and <italic>Klebsiella pneumoniae</italic> in the pediatric population of Qatar.</p></sec><sec><title>Methods</title><p>Whole-genome sequencing was performed on ESBL-producing <italic>E. coli</italic> and <italic>K. pneumoniae</italic> isolates recovered from screening and clinical specimens from pediatric patients at Sidra Medicine in Doha from January to December 2018.</p></sec><sec><title>Results</title><p>A total of 327 ESBL producers were sequenced: 254 <italic>E. coli</italic> and 73 <italic>K. pneumoniae</italic>. Non-susceptibility rates to non-β-lactam antibiotics for both species were 18.1 and 30.1% for gentamicin, 0.8 and 4.1% for amikacin, 41.3 and 41.1% for ciprofloxacin, and 65.8 and 76.1% for cotrimoxazole. The most common sequence types (STs) were ST131 (16.9%), ST38 and ST10 (8.2% each) in <italic>E. coli</italic> and ST307 (9.7%), and ST45 and ST268 (6.9% each) in <italic>K. pneumoniae</italic>. CTX-M type ESBLs were found in all but one isolate, with CTX-M-15 accounting for 87.8%. Among other β-lactamases, TEM-1B and OXA-1 were coproduced in 41 and 19.6% of isolates. The most common plasmid-mediated quinolone resistance genes cocarried were <italic>qnr A/B/E/S</italic> (45.3%). Ninety percent of gentamicin non-susceptible isolates harbored genes encoding AAC(3) enzymes, mainly <italic>aac(3)-IIa</italic>. Only two of 57 isolates harboring <italic>aac(6′)-Ib-cr</italic> were non-susceptible to amikacin. Chromosomal mutations in genes encoding DNA gyrase and topoisomerase IV enzymes were detected in 96.2% fluoroquinolone-non-susceptible <italic>E. coli</italic> and 26.7% fluoroquinolone-non-susceptible <italic>K. pneumoniae</italic>.</p></sec><sec><title>Conclusion</title><p>Our data show that CTX-M enzymes are largely the most prevalent ESBLs in children in Qatar with a predominance of CTX-M-15. Carbapenem-sparing options to treat ESBL infections are limited, given the frequent coproduction of OXA-1 and TEM-1B enzymes and coresistance to antibiotic classes other than β-lactams.</p></sec>