# Prevalence of Biofilm-Forming and Antibiotic-Resistant Coagulase-Negative Staphylococci Isolated from Hospitalized Patients in an Orthopedic Clinic

## TL;DR

This study examines antibiotic-resistant and biofilm-forming coagulase-negative staphylococci from hospitalized orthopedic patients in Slovakia.

## Contribution

The study identifies the prevalence of MRCoNS with multiple drug resistance and biofilm-forming genes in a clinical setting.

## Key findings

- 28 MRCoNS isolates were identified, with S. epidermidis and S. hominis being the most common.
- High resistance rates were observed for ampicillin, oxacillin, rifampicin, trimethoprim, and erythromycin.
- 12 isolates showed MDR, strong efflux pump activity, and biofilm formation, emphasizing clinical challenges.

## Abstract

Methicillin-resistant coagulase-negative staphylococci (MRCoNS) are a major cause of infectious diseases, owing to their ability to form biofilms and colonize community and hospital environments. MRCoNS strains were identified using biochemical tests, an MALDI-TOF MS analyzer, and PCR-based 16S rRNA gene confirmation. This study was designed to assess antibiotic resistance and biofilm-forming capacity and to determine the presence of the mecA, mecC, agrA, srtA, icaABCD, bap, fnbAB, and clfAB genes in MRCoNS isolates. From patients undergoing random screening during hospitalization in the Orthopedics Clinic in Slovakia, 28 strains of MRCoNS were identified: S. epidermidis (n = 10), S. hominis (n = 8), S. haemolyticus (n = 4), S. lugdunensis (n = 3), while S. simulans, S. pasteuri, and S. warneri were detected only once. The highest rates of resistance were observed for ampicillin, oxacillin, rifampicin, trimethoprim (100%), and erythromycin (62%). The mecA gene was detected in 12 analyzed isolates. In 12 isolates, MDR, strong efflux pump activity, and strong or moderate biofilm formation were simultaneously detected. Our findings highlight the problems posed by biofilm-forming, resistant CoNS in hospitalized patients and the importance of diagnostics, separation, rapid treatment, and proper hospital hygiene.