Restricted Gene Flow among Hospital Subpopulations of Enterococcus faecium

Peer reviewe

Dynamics of ampicillin-resistant Enterococcus faecium clones colonizing hospitalized patients: data from a prospective observational study

<p>Abstract</p> <p>Background</p> <p>Little is known about the dynamics of colonizing <it>Enterococcus faecium </it>clones during hospitalization, invasive infection and after discharge.</p> <p>Methods</p> <p>In a prospective observational study we compared intestinal <it>E. faecium </it>colonization in three patient cohorts: 1) Patients from the Hematology Unit at the University Hospital Basel (UHBS), Switzerland, were investigated by weekly rectal swabs (RS) during hospitalization (group 1a, n = 33) and monthly after discharge (group 1b, n = 21). 2) Patients from the Intensive Care Unit (ICU) at the University Medical Center Utrecht, the Netherlands (group 2, n = 25) were swabbed weekly. 3) Patients with invasive <it>E. faecium </it>infection at UHBS were swabbed at the time of infection (group 3, n = 22). From each RS five colonies with typical <it>E</it>. <it>faecium </it>morphology were picked. Species identification was confirmed by PCR and ampicillin-resistant <it>E. faecium </it>(ARE) isolates were typed using Multiple Locus Variable Number Tandem Repeat Analysis (MLVA). The Simpson's Index of Diversity (SID) was calculated.</p> <p>Results</p> <p>Out of 558 ARE isolates from 354 RS, MT159 was the most prevalent clone (54%, 100%, 52% and 83% of ARE in groups 1a, 1b, 2 and 3, respectively). Among hematological inpatients 13 (40%) had ARE. During hospitalization, the SID of MLVA-typed ARE decreased from 0.745 [95%CI 0.657-0.833] in week 1 to 0.513 [95%CI 0.388-0.637] in week 3. After discharge the only detected ARE was MT159 in 3 patients. In the ICU (group 2) almost all patients (84%) were colonized with ARE. The SID increased significantly from 0.373 [95%CI 0.175-0.572] at week 1 to a maximum of 0.808 [95%CI 0.768-0.849] at week 3 due to acquisition of multiple ARE clones. All 16 patients with invasive ARE were colonized with the same MLVA clone (<it>p </it>< 0.001).</p> <p>Conclusions</p> <p>In hospitalized high-risk patients MT159 is the most frequent colonizer and cause of invasive <it>E. faecium </it>infections. During hospitalization, ASE are quickly replaced by ARE. Diversity of ARE increases on units with possible cross-transmission such as ICUs. After hospitalization ARE are lost with the exception of MT159. In invasive infections, the invasive clone is the predominant gut colonizer.</p

Intra- and Interspecies Genomic Transfer of the Enterococcus faecalis Pathogenicity Island

Enterococci are the third leading cause of hospital associated infections and have gained increased importance due to their fast adaptation to the clinical environment by acquisition of antibiotic resistance and pathogenicity traits. Enterococcus faecalis harbours a pathogenicity island (PAI) of 153 kb containing several virulence factors including the enterococcal surface protein (esp). Until now only internal fragments of the PAI or larger chromosomal regions containing it have been transfered. Here we demonstrate precise excision, circularization and horizontal transfer of the entire PAI element from the chromosome of E. faecalis strain UW3114. This PAI (ca. 200 kb) contained some deletions and insertions as compared to the PAI of the reference strain MMH594, transferred precisely and integrated site-specifically into the chromosome of E. faecalis (intergenic region) and Enterococcus faecium (tRNAlys). The internal PAI structure was maintained after transfer. We assessed phenotypic changes accompanying acquisition of the PAI and expression of some of its determinants. The esp gene is expressed on the surface of donor and both transconjugants. Biofilm formation and cytolytic activity were enhanced in E. faecalis transconjugants after acquisition of the PAI. No differences in pathogenicity of E. faecalis were detected using a mouse bacteraemia and a mouse peritonitis models (tail vein and intraperitoneal injection). A 66 kb conjugative pheromone-responsive plasmid encoding erm(B) (pLG2) that was transferred in parallel with the PAI was sequenced. pLG2 is a pheromone responsive plasmid that probably promotes the PAI horizontal transfer, encodes antibiotic resistance features and contains complete replication and conjugation modules of enterococcal origin in a mosaic-like composition. The E. faecalis PAI can undergo precise intra- and interspecies transfer probably with the help of conjugative elements like conjugative resistance plasmids, supporting the role of horizontal gene transfer and antibiotic selective pressure in the successful establishment of certain enterococci as nosocomial pathogens

Provincial Dietary Intake Study (PDIS) : prevalence and sociodemographic determinants of the double burden of malnutrition in a representative sample of 1 to under 10-year-old children from two urbanized and economically active provinces in South Africa

CITATION: Senekal, M., et al. 2019. Provincial Dietary Intake Study (PDIS) : prevalence and sociodemographic determinants of the double burden of malnutrition in a representative sample of 1 to under 10-year-old children from two urbanized and economically active provinces in South Africa. International Journal of Environmental Research and Public Health, 16(18):3334, doi:10.3390/ijerph16183334.The original publication is available at http://www.mdpi.comThe objective of this study was to determine the prevalence and socio-demographic predictors of malnutrition in two urbanized economically active provinces (Gauteng N = 733, Western Cape N = 593) in South Africa. A multistage stratified cluster random sampling design was applied. Fieldworkers visited homes, measured children aged 1- +2 SD ≤ +3 SD] and 7.0% obese (BAZ > +3 SD). In 5– 1 (OR 2.39), while being in the third wealth quintile was protective (OR = 0.62). Results indicate that stunting and overweight/obesity are still present at concerning levels, especially in the under-five age group.https://www.mdpi.com/1660-4601/16/18/3334Publisher's versio

Provision of on-site medical care to patients with hepatitis C in drug treatment units.

Substance abusers are at high risk for hepatitis C (HCV) infection and also constitute a group that is medically underserved and hard to reach. We conducted a nationwide survey with 445 randomly selected drug treatment units in the United States to determine unit and patient characteristics associated with the provision of on-site medical services for HCV-infected drug users. Eighty-four percent of the 322 units that estimated having at least one HCV-infected patient reported that they provided patients with HCV-related medical care. Drug treatment units were more likely to provide at least some of this care on site if they were residential, part of a network, or affiliated with a hospital; had medical staff; and required that their patients undergo a medical examination before entering treatment. Some organizational factors appear to influence the provision of on-site medical services to HCV-positive patients in drug treatment units. Further research on the role of such factors could inform the development of effective models of care for patients with hepatitis C in drug treatment organizations

Dogs Are a Reservoir of Ampicillin-Resistant Enterococcus faecium Lineages Associated with Human Infections▿

Ampicillin resistance is a marker for hospital-associated Enterococcus faecium. Feces from 208 dogs were selectively screened for the occurrence of ampicillin-resistant E. faecium (AREF). AREF was detected in 42 (23%) of 183 dogs screened in a cross-sectional study in the United Kingdom and in 19 (76%) of 25 dogs studied longitudinally in Denmark. AREF carriage was intermittent in all dogs studied longitudinally. Multilocus sequence typing of 63 canine AREF isolates revealed the presence of 13 distinct sequence types. Approximately 76% of the isolates belonged to hospital-adapted clonal complex 17 (CC17), including those of sequence types ST-78 and ST-192, which are widespread in European and Asian hospitals. Longitudinal screening of 18 healthy humans living in contact with 13 of the dogs under study resulted in the identification of a single, intermittent CC17 carrier. This person carried one of the sequence types (ST-78) recovered from his dog. Based on PCR and Southern hybridization analyses, the putative virulence gene cluster from orf903 to orf907 was widespread in canine AREF isolates (present in 97%), whereas orf2351 (present in 26% of isolates) and orf2430 (present in 31%) were strongly associated with CC17-related sequence types (P < 0.05). Surprisingly, esp and hyl were not detected in any of the isolates. The antimicrobial resistance profiles of canine AREF isolates generally differed from those previously described for clinical human isolates. The results indicate that dogs are frequent carriers of CC17-related lineages and may play a role in the spread of this nosocomial pathogen. The distinctive virulence and antimicrobial resistance profiles observed among canine AREF isolates raise interesting questions about the origin and evolution of the strains causing human infections

Depression in the South African workplace

Depression is a common psychiatric disorder and can be costly, having a significant impact on the individual and employers. The South African Depression and Anxiety Group (SADAG) in partnership with HEXOR, with the support of Lundbeck, undertook research into depression in the workplace, because South African information is not available on this topic. It provides insight into the prevalence of depression within the workplace in South Africa, as well as the impact of depression on the employees and employers in terms of sick leave and levels of productivity, especially when the symptoms include cognitive impairment. It is apparent that stigma plays a pivotal role in the reasons for non-disclosure to employers. It further highlights the magnitude of awareness, early detection and the provision of a holistic support system within the work environment, free from bias, to ensure that optimum benefit can be achieved for both employer and employee