6 research outputs found
Salmonella Infections among Pediatric Population in Qatar: Phenotypic Resistance and Associated Genotypic Determinants
Salmonella is a significant public health burden worldwide and being the
most common bacterial diarrheal illness among infants and young children. In
the last few years, Qatar reports a high incidence of salmonellosis outbreaks
coupled with a significant increase of Multidrug-Resistant (MDR) among
pediatric populations every year. This study aims to elucidate the molecular
mechanisms underlying resistance to ceftriaxone, cefepime, amoxicillinclavulanate
tetracycline, trimethoprim-sulfamethoxazole, chloramphenicol, and
azithromycin among Salmonella isolated from the pediatric population. A total
of 246 Salmonella isolates were collected from children under 18 years old
admitted to the Pediatric Emergency Center (PEC), Hamad Medical Corporation
(HMC) from Jan. 2018 to Dec 2019 with gastroenteritis. Isolates were tested
for antibiotic susceptibility against nineteen relevant antibiotics using E-test.
Resistance was confirmed using PCR-specific primers for 38 genes. Resistance
was detected against 14 antibiotics, and 38.2% of isolates were resistant to
at least one antibiotic. Overall, we reported 23.9%, resistance to tetracycline
21.1%, ampicillin 18.7%, AMC, and 13% sulfamethoxazole-trimethoprim.
Further, 16.2% of the isolates were Multidrug-Resistant (MDR), with 4.1%
being Extended-Spectrum β Lactamase (ESBL) producers. 90% of ESBL
producers harbored one of bla CTX-M-Group. Class 1 AMC resistant samples
showed the highest resistance to different antibiotics. Our results indicate a high
antimicrobial resistance pattern of Salmonella and the presence of Class (1)
cassette that involves the transmission and expression of the resistance among
AMC resistance isolates, which might lead to increased multi-drug resistance.
This study provides evidence guidance to activate and implement the pillars
of an antimicrobiThis work was supported by Qatar University collaborative grant no.: QUCG-BRC-19/20
Comparing Quantitative and Qualitative Methods for Detecting the In Vitro Activity of Colistin against Different Gram-Negative Bacilli
The surge in the prevalence of Multidrug-Resistant (MDR) Gram-negative
bacterial infections with limited treatment led to colistin reusing to treat MDR
infections. This study aimed to determine economical, simple, and reliable colistin
susceptibility testing methods as an alternative to the microdilution technique.
We compared seven colistin susceptibility testing methods, including quantitative
and qualitative, namely: Disk diffusion, E-test, ComASPTM SensiTest Colistin,
Colistin broth disk elution, and colistin agar test CHROMagarTM COL-APSE, and
BD Phoenix ID/AST automated identification and susceptibility testing system
to the gold standard Broth Microdilution (BMD). Whole-genome sequencing
was performed on all isolates to determine if the genetic resistant factors affect
the phenotypic profile of the colistin resistance. Our results revealed that disk
diffusion is still an ineffective method for measuring colistin susceptibility in
Gram-negative Bacilli with the highest major error (31.75%), the lowest Kappa 0
(0%), and categorical agreement (68.25%) values. Phoenix, and CompASPTM
SensiTest colistin methods have remained superior in reproducibility, sturdiness,
and simplicity of use, similar to the currently recommended broth microdilution
procedure; with high sensitivity of 95.56%, and 97.73%, specificity of 95.24, and
100%, and Kappa values of 0.89 and 0.95, respectively. This study revealed
that Phoenix, and ComASPTM SensiTest colistin methods(UREP26-024-1-002)from the Qatar National Research Fund (QNR
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