Pulsed-Field Gel Electrophoresis Used for Typing of Extended-Spectrum-β-Lactamases- Producing Escherichia coli Isolated from Infant ҆S Respiratory and Digestive System

Abstract

Escherichia coli infections are becoming increasingly difficult to treat because of emerging antimicrobial resistance, mostly to expanded-spectrum cephalosporins, due to the production of extended-spectrum β-lactamases (ESBLs).Despite extensive studies of ESBL- producing E.coli in adult patients, there is a lack of information about the epidemiology and spread of ESBL organisms in pediatric population. The aim of this study was to examine the gastrointestinal tract as an endogenous reservoir for the respiratory tract colonization with ESBL- E. coli in children, hospitalized because of the severity of the respiratory illness. The study group consists of 40 children with ESBL-producing E. coli strains isolated from the sputum and from the rectal samples. A control group of 15 E. coli isolated from rectal swabs of healthy children were included in the analysis. The comparison of the strains was done by using antimicrobial susceptibility patterns of the stains, and pulsed field gel electrophoresis was performed for molecular typing, using XbaI digestion. 90% of the compared pairs of strains in the study group were with identical antimicrobial susceptibility patterns and indistinguishable in 79.2% by the obtained PFGE – profiles.33.3% (5/15) of confirmed E. coli strains from the control group were found to be ESBL – producers. Resulting band profiles of all isolates demonstrated presence of 12 pulsotypes, with 100% similarity within the pulsotypes. Although, some isolates obtained from different patients were genetically indistinguishable, these strains were not hospital acquired, as none of the patients satisfied the criteria for hospital acquired pneumonia, and there was a lack of an obvious transmission chain. All ESBL –E. coli isolated from sputum in clinical cases were obtained from patients under the age of one. According to the resistance profile of the compared pairs and the PFGE comparison of all isolates, it can be concluded that the gastrointestinal tract is the main reservoir of ESBL-E. coli. Small age in infants is a risk factor for translocation of bacteria, enabling the colonization of the respiratory tract.

β-Lactamase Genes (blaCTX-M, blaSHV, blaTEM, blaOXA1 and blaOXA2) and Phylogenetic Groups in ESBL Producing Commensal Escherichia coli Isolated from Faecal Samples from Dairy Farm in the Municipality of Debar

“…However, these results are lower than the ones reported for ESBL phenotype in dairy cattle from China (45.9%), Egypt (46.6%) and Nigeria (63.2%) (19,20,21). Similar results as in this survey were obtained in a study that involved an outpatient setting in Nepal, where ESBL confirmed phenotype was 25.8% (22), in uropathogenic E. coli isolated from outpatients in Iran (23) and in rectal samples from healthy infants, where ESBL E. coli was confirmed in 33.3% (24). Numerous studies have reported a high prevalence of ESBL producing E. coli in environmental samples, especially from farm environments.…”

Tracing of Listeria monocytogenes Contamination Routes in Fermented Sausage Production Chain by Pulsed-Field Gel Electrophoresis Typing

“…Ready-to-eat meat production facilities have been found to be sources of persistent L. monocytogenes strains due to the increased adhesion and biofilm capacity of the strains [15]. The contamination routes of foodborne pathogens may be difficult to trace; however, molecular typing has been proposed as a reliable tool for epidemiological purposes [16,17]. Recently, Véghová et al [18] applied PFGE analysis in the molecular typing of L. monocytogenes strains from traditional meat production facilities and confirmed the reliability of the method to reveal persistent contamination over a number of years in the same facility.…”

Sputum Quality Assessment Regarding Sputum Culture for Diagnosing Lower Respiratory Tract Infections in Children

“…First of all, instead of expectorating the sputum, children tend to swallow it and usually have difficulty producing an adequate amount of specimen [1]. Moreover, compared to adults, children have higher colonisation rate of the respiratory tract with bacteria such as Streptococcus pneumoniae, Haemophilus influenza and especially in infants, high colonisation rate with Escherichia coli [2], [3], [4]. The latter increases the likelihood of contamination of the sputum specimen during its collection.…”