Characteristics related to antimicrobial resistance and biofilm formation of widespread methicillin-resistant Staphylococcus epidermidis ST2 and ST23 lineages in Rio de Janeiro hospitals, Brazil

Abstract

Staphylococcus epidermidis is a leading cause of hospital-acquired infections, mostly associated with the use of medical devices in seriously ill or immunocompromised patients. Currently, the characteristics of methicillin-resistant S. epidermidis (MRSE) isolates from Rio de Janeiro hospitals are unknown. In this study, staphylococcal chromosomal cassette mec (SCCmec) types, antimicrobial susceptibility profiles, biofilm formation genes, and multilocus sequence types (MLST) were investigated in 35 MRSE clinical isolates. The collection of isolates was previously well characterized by pulsed-field gel electrophoresis (PFGE) into 2 main genotypes (A and B, 22 isolates) and 10 sporadic genotypes (13 isolates). MLST revealed a total of 8 different sequence types (STs), but ST2 and ST23, which were icaAB-positive, represented the majority (71.4%) of MRSE isolates tested. Almost all isolates (91.4%) belonged to clonal complex 2. SCCmec types III and IV were identified among 71.4% of the isolates, while the remaining was nontypeable. The predominant MRSE genotypes were defined as SCCmec type III/ST2 (PFGE type A) and SCCmec type IV/ST23 (PFGE type B) isolates, which were both associated with high antimicrobial resistance and presence of biofilm-related genes.

Genetic determinants and biofilm formation of clinicalStaphylococcus epidermidisisolates from blood cultures and indwelling devises

“…About 83.33% of these isolates were carriers of IS256 and equally of SCCmec types II and III. Therefore, our data support the data of Li et al [49] and Iorio et al [50]. Our ST23 isolates, similar to those of Iorio et al [50], were exclusively ica-positive.…”

“…Therefore, our data support the data of Li et al [49] and Iorio et al [50]. Our ST23 isolates, similar to those of Iorio et al [50], were exclusively ica-positive. However, Iorio et al [50] assigned the ST23 isolates to SCCmec type IV, whereas our ST23 isolates were grouped into SCCmec I and IV.…”

“…Our ST23 isolates, similar to those of Iorio et al [50], were exclusively ica-positive. However, Iorio et al [50] assigned the ST23 isolates to SCCmec type IV, whereas our ST23 isolates were grouped into SCCmec I and IV. Differences were also observed between the studies concerning ST5 and ST10.…”

“…Thirty-fi ve oxacillin-resistant S. epidermidis isolates from Brazil were studied by Iorio et al [50]. ST2 (45.7%) was the predominant sequence type, followed by ST23 (25.7%).…”

Characterization of Ocular Methicillin-Resistant Staphylococcus epidermidis Isolates Belonging Predominantly to Clonal Complex 2 Subcluster II

“…Pulsed-field gel electrophoresis (PFGE) is the most discriminatory method for characterizing S. epidermidis and has been widely used for studying the dissemination of MRSE clones in hospitals and community (19)(20)(21)(22). However, its application has been more restricted to short-term epidemiology for characterization of hospital outbreaks (18,21).…”