Molecular characterization of extended spectrum β -lactamases enterobacteriaceae causing lower urinary tract infection among pediatric population.

The β-lactam antibiotics have traditionally been the main treatment of Enterobacteriaceae infections, nonetheless, the emergence of species producing β- Lactamases has rendered this class of antibiotics largely ineffective. There are no published data on etiology of urinary tract infections (UTI) and antimicrobial resistance profile of uropathogens among children in Qatar. The aim of this study is to determine the phenotypic and genotypic profiles of antimicrobial resistant Enterobacteriaceae among children with UTI in Qatar. Bacteria were isolated from 727 urine positive cultures, collected from children with UTI between February and June 2017 at the Pediatric Emergency Center, Doha, Qatar. Isolated bacteria were tested for antibiotic susceptibility against sixteen clinically relevant antibiotics using phoenix and Double Disc Synergy Test (DDST) for confirmation of extended-spectrum beta-lactamase (ESBL) production. Existence of genes encoding ESBL production were identified using polymerase chain reaction (PCR). Statistical analysis was done using non-parametric Kappa statistics, Pearson chi-square test and Jacquard's coefficient. 201 (31.7%) of samples were confirmed as Extended Spectrum β -Lactamases (ESBL) Producing Enterobacteriaceae. The most dominant pathogen was 166 (83%) followed by 22 (11%). Resistance was mostly encoded by CTX-M (59%) genes, primarily CTX-MG1 (89.2%) followed by CTX-MG9 (7.7%). 37% of isolated bacteria were harboring multiple genes (2 genes or more). isolates were categorized into 11 clusters, while were grouped into five clonal clusters according to the presence and absence of seven genes namely TEM, SHV, CTX-MG1, CTX-MG2, CTX-MG8 CTX-MG9 CTX-MG25. Our data indicates an escalated problem of ESBL in pediatrics with UTI, which mandates implementation of regulatory programs to reduce the spread of ESBL producing Enterobacteriaceae in the community. The use of cephalosporins, aminoglycosides (gentamicin) and trimethoprim/sulfamethoxazole is compromised in Qatar among pediatric population with UTI, leaving carbapenems and amikacin as the therapeutic option for severe infections caused by ESBL producers

First detection of TEM-116 extended-spectrum β-lactamase in a Providencia stuartii isolate from a Tunisian hospital

Purpose: To study the resistance to third-generation cephalosporins in Providencia stuartii strain isolated from hospitalized patient in Tunisia and to identify the responsible genes Materials and Methods: This strain was analysed by PCR and sequencing to identify the genes responsible for the β-lactamase resistance phenotypes. The transferability of the phenotypes was tested by conjugation to Escherichia coli J53. The isoelectric point was determinate by isoelectrofocalisation. Results: This resistance was carried by a 60 kb plasmid that encoded a β-lactamase with a pI of 5.4. This β-lactamase revealed identity with the blaTEM-1 gene encoding the TEM-1 β-lactamase, except for a replacement of the Val residue at position 84 by Ile, and the Ala residue at position 184 by Val. These two mutations were encountered in TEM-116 β-lactamase. Conclusion: This study demonstrates the first description of TEM-116 in the P. stuartii species in the world and the first one in a Tunisian hospital