Detection of -Lactamase-Producing Enterococcus faecalis and Vancomycin-Resistant Enterococcus faecium Isolates in Human Invasive Infections in the Public Hospital of Tandil, Argentina

TEDIM AS; BASUALDO JA; RODRIGUEZ BAÑOS; LISSARRAGUE S; SCHELL C; SPARO M; COQUE T

Pathogens

MDPI Journals

Lugar: Basel; Año: 2020 vol. 9 p. 1 - 11

The study?s aim was to analyze the population structure of enterococci causing humaninvasive infections in a medium-sized Argentinian Hospital coincidental with a 5 year-periodof increased recovery of antibiotic resistant enterococci (2010?2014). Species identification(biochemical testing/MALDI-TOF-MS), antimicrobial susceptibility (disk-diusion) and clonalrelatedness (PFGE/MLST/BAPS) were determined according to standard guidelines. -lactamaseproduction was determined by a nitrocefin test and confirmed by PCR/sequencing. The isolateswere identified as Enterococcus faecalis and Enterococcus faecium at a 2:1 ratio. Most of the E. faecalisisolates, grouped in 25 PFGE-types (ST9/ST179/ST236/ST281/ST388/ST604/ST720), were resistant tohigh-levels (HLR) of gentamicin/streptomycin. A ST9 clone (bla+/HLR-gentamicin) was detectedin patients of dierent wards during 2014. E. faecium isolates were grouped in 10 PFGE-types(ST25/ST18/ST19/ST52/ST792), with a low rate of ampicillin resistance. Five vancomycin-resistantE. faecium, three vanA (ST792/ST25) and two vanB (ST25) were detected. The ST25 clone carried eithervanA or vanB. The recovery of a bla+-ST9-E. faecalis clone similar to that described in the late 1980s inArgentina suggests the possibility of a local hidden reservoir. These results reflect the relevance oflocal epidemiology in understanding the population structure of enterococci as well as the emergenceand spread of antimicrobial resistance in predominant enterococcal clonal lineages.