Prevalence Of Enterococcus Species Research Articles

Virulence determinants and biofilm formation in clinical isolates of Enterococcus: A cross-sectional study

Objective: To evaluate the relationship between biofilm formation and incidence of virulence determinants in clinical isolates of Enterococcus. Methods: In this cross-sectional study, the clinical isolates of Enterococcus strains were collected from the university teaching hospitals in Ahvaz, Iran from June 2017 to June 2018. Then, the prevalence of Enterococcus species, antibiotic resistance, virulence factors, and biofilm-producing ability were determined. Results: Of the 119 tested isolates, 17 (14.3%) were Enterococcus faecalis, 72 (60.5%) were Enterococcus faecium and 30 (25.2%) were other Enterococcus spp. Gelatinase was detected in 97 (81.5%) isolates, enterococcal surface protein in 41 (34.5%) isolates, serine protease in 39 (32.8%) cases, accessory colonization factor in 111 (93.3%) cases and pathogenicity islands in 17 (14.3%) cases. The biofilm formation ability was observed in 75 (63.0%) of all isolates and the association between the presence of enterococcal surface protein gene and biofilm formation was statistically significant. Higher resistance to vancomycin, gentamycin, and teicoplanin was indicated in Enterococcus faecium with 81.8%, 58.4%, and 85.7% resistance rate, respectively. All Enterococcus faecalis isolates were sensitive to teicoplanin and vancomycin. Conclusions: The presence of antibiotic-resistance with several virulence factors in Enterococcus spp has become a concern. High prevalence of enterococcal surface protein gene among biofilm- producing isolates suggests a potential relation between biofilm formation and the enterococcal surface protein gene, and further studies are needed to identify the mechanism of biofilm inhibition.

The Antimicrobial Resistance and Prevalence of Enterococcus Species in Saudi Arabia

The Antimicrobial Resistance and Prevalence of Enterococcus Species in Saudi Arabia

Prevalence, antimicrobial resistance, virulence gene, and class 1 integrons of Enterococcus faecium and Enterococcus faecalis from pigs, pork and humans in Thai-Laos border provinces

This study aimed to determine prevalence, antimicrobial resistance, virulence genes, and Class 1 integrons of Enterococcus faecium (E. faecium) and Enterococcus faecalis (E. faecalis) from pigs, pork and humans in Thailand-Laos border provinces. Six hundred and forty-eight rectal and carcass swab samples from border provinces of Thailand (n=359) and Lao PDR (n=289) were collected and examined from September 2013 to October 2014. The overall prevalence of Enterococcus species was 483 of 648 (75%), comprising E. faecium (359 of 483, 74.3%) and E. faecalis (124 of 483, 25.7%). The occurrence of E. faecium in pigs, pig carcasses, retail pork, and humans in Thailand was 80.6%, 73.8%, 77.6%, and 67%, respectively. The prevalence of E. faecium was higher in Laos (65.7%) than Thailand (47.1%) (P<0.001). Conversely, E. faecalis was more common in Thailand (24.2%) than Laos (12.8%) (P<0.001). The E. faecium and E. faecalis isolates were resistant to all antimicrobials except vancomycin. High resistance was first observed to tetracycline, erythromycin and streptomycin, followed by gentamicin, ampicillin and chloramphenicol. Both E. faecium (7%) and E. faecalis (0.8%) carried empty Class 1 integrons: E. faecium carried gel (6.4%) and esp (0.8%), while E. faecalis carried agg (41.9%), cylA (36.3%), gel (60.5%), and esp (42.7%). This study revealed a variable distribution of antimicrobial resistance and virulence genes among E. faecium and E. faecalis from pigs, pig products and humans in Thai-Laos border provinces. These pathogens may serve as potential reservoirs for the maintenance and widespread dissemination of antimicrobial resistance and virulence determinants from animals to humans via the food chain.

Antimicrobial Resistance, Virulence Determinants, and Biofilm Formation of Enterococcus Species From Ready-to-Eat Seafood.

Enterococcus species form an important population of commensal bacteria and have been reported to possess numerous virulence factors considered significantly important in exacerbating diseases caused by them. The present study was designed to characterize antibiotic-resistant and virulent enterococci from ready-to-eat (RTE) seafood. A total of 720 RTE shrimp samples comprising sauced shrimp (n = 288), boiled shrimp (n = 216), and smoked shrimp (n = 216) obtained from open markets in Delta State, Nigeria, were assessed. Standard classical methods and polymerase chain reaction (PCR) were used in identifying the Enterococcus species. Potential virulence factors (β-hemolysis, gelatinase activity, S-layer, and biofilm formation) were assessed using standard procedures. The antibiotic susceptibility profile of the identified enterococci isolates was assayed using the Kirby–Bauer disc diffusion method. PCR was further used to screen selected antibiotic resistance and virulence genes. Prevalence of Enterococcus species from shrimp varieties is as follows: sauced, 26 (9.03%); boiled, 6 (2.78%); and smoked, 27 (12.50%), with an overall prevalence of 59 (8.19%) based on the occurrence of black hallow colonies after incubation. Enterococcus species detected include E. faecalis, 17 (28.8%); E. faecium, 29 (49.2%); E. gallinarum, 6 (10.2%); E. casseliflavus, 2 (3.4%); E. hirae, 3 (5.1%); and E. durans, 2 (3.4%). Biofilm occurrence among the shrimp varieties is as follows: 19/26 (73.1%) for sauced shrimps, 5/6 (83.3%) for boiled shrimps, and 16/27 (59.3%) for smoked shrimps. The phenotypic expression of the enterococci virulence revealed the following: S-layer, 59 (100%); gelatinase production, 19 (32.2%); and β-hemolysis, 21 (35.6%). An average of 3–11 virulence genes were detected in the Enterococcus species. The resistance profile of Enterococcus species is as follows: erythromycin, 29 (49.2%); vancomycin, 22 (37.3%); and tetracycline, 27 (45.8%). The frequency of occurrence of antibiotic resistance genes from the phenotypic resistant enterococci isolates to the macrolide, glycopeptide, and tetracycline antibiotics is as follows: ermA, 13/29 (44.8%); vanA, 14/22 (63.6%); tetA, 14/27 (51.9%); tetM, 15/27 (55.6%); ermB, 4/29 (13.8%); and vanB, 5/22 (22.7%). Findings from this study reveal the antibiotic resistance of enterococci strains of such species as E. durans, E. casseliflavus, E. gallinarum, and E. hirae. This study further revealed that RTE food products are reservoirs of potential virulent enterococci with antibiotic-resistant capabilities. This provides useful data for risk assessment and indicates that these foods may present a potential public health risk to consumers.

English

IntroductionEnterococci are part of the normal intestinal flora of humans and animals but have also emerged as important pathogens responsible for serious infections in hospital and community acquired infections. According to recent surveys, Enterococci remain in the top 3 most common pathogens that cause nosocomial infections. AimTo process all the clinical samples from various departments in our hospital, for the isolation of Enterococci sp. To speciate the isolates & to have the resistance pattern of the isolates to Vancomycin Methods and MaterialA total of 928 samples were collected from both out patients and in patients in all clinical departments and transported to microbiology laboratory. Specimens were processed by inoculating on to Mac Conkeys agar, blood agar, nutrient agar and Pfizer selective media and incubated at 370C for 24 48 hours. Enterococci were identified by their typical arrangement in Gram stain, Bile esculin test and salt tolerance test. Speciation was done by subjecting the isolates to a battery of biochemical tests. Antimicrobial susceptibility patterns were determined by performing Kirby-Bauer disc diffusion method and Minimum Inhibitory Concentration (MIC) values were identified by Tube & Agar dilution method. ResultsA total of 928 samples. Among these, 647 (69.72%) were culture positive with different isolates and 281 (30.28%) were culture negative. Among 647 culture positive cases, 100 (15.46%) were Enterococcus faecalis. Antimicrobial susceptibility & MIC done as per standard protocols. The E. Faecalis showed 99% sensitive to Vancomycin. The resistance to Vancomycin was further confirmed by MIC both Agar &Tube dilution methods, in which the MIC was: 32μg/ml in one isolate. ConclusionsSpecies level identification of Enterococcus is not only important for epidemiological study, but also for analysing the drug resistant pattern. Effective detection of Vancomycin resistance in laboratory helps in reducing the morbidity and mortality due to VRE in hospitalized patients. Key wordsBlood agar, Mac Conkeys agar, Bile esculin, Vancomycin resistant Enterococci, Minimum inhibitory concentration. International Journal of Medical and Clinical Research ISSN:0976-5530 & E-ISSN:0976-5549, Volume 3, Issue 4, 2012 Citation: Sunilkumar Jada and Karthika Jayakumar (2012) Prevalence of Enterococcus species from various clinical specimens in Shri Sathya Sai Medical College & Research Institute with special reference to speciation and their resistance to Vancomycin. International Journal of Medical and Clinical Research, ISSN:0976-5530 & E-ISSN:0976-5549, Volume 3, Issue 4, pp.-154-160. Copyright: Copyright©2012 Sunilkumar Jada and Karthika Jayakumar. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited. Introduction Enterococci are part of the normal intestinal flora of humans and animals but have also emerged as important pathogens responsible for serious infections in hospital and community acquired infections. The genus Enterococcus includes more than 17 species, but only a few cause clinical infections in humans [1]. Enterococci were originally classified as enteric gram-positive cocci and later included in the genus Streptococcus. In the 1930s, with the establishment of the Lancefield serological typing system, Enterococci were classified as group D streptococci and were differentiated from the non-Enterococcal group D streptococci such as Streptococcus bovis by distinctive biochemical