Molecular Characterization and Resistant Spectrum of Enterococci Isolated from a Haematology Unit in China

The present study screened clinical isolates of E. faecalis and E. faecium to determine resistant spectrum and the potential virulence genes characterization among them of haematology patients.

Clinical Enterococci isolates were obtained from a haematology unit in a tertiary care hospital in China.

Among 125 isolates available for the investigation, 46 were identified as E. faecium, and 79 were E. faecalis. Urine was the most common source (82, 65.6%). E. faecium isolates were more resistant than E. faecalis. Among E. faecium, maximum resistance was seen against PEN 93.5% and AMP 93.5% followed by CIP 87%. Eight vancomycin-resistant E. faecium (VREfm) isolates were obtained, positive for vanA genotype. Of 125 Enterococci isolates, 67(53.6%) were acm, and 42.4%, 25.6%, 25.6%, 24.8%, 23.2%, 20.8%, 10.4% and 7.2% of isolates were positive for esp, cylL-A, asa 1, cylL-S, cpd, cylL-L, gel-E and ace, respectively. E. faecalis isolates have more virulence genes (VGs) than E. faecium. MLST analysis of VREfm identified three different STs (ST17, ST78 and ST203).

The study provides the molecular characterization and resistant spectrum of Enterococci isolated from a haematology unit in China. Molecular analysis showed that all VREfm isolates belonged to pandemic clonal complex-17(CC17), associated with hospital-related isolates. Therefore, determining resistant spectrum and virulence characterization is crucial for the prevention and control of the spread of nosocomial infections caused by Enterococci in the haematology unit.