J. Huebner et al., ENDEMIC NOSOCOMIAL TRANSMISSION OF STAPHYLOCOCCUS-EPIDERMIDIS BACTEREMIA ISOLATES IN A NEONATAL INTENSIVE-CARE UNIT OVER 10 YEARS, The Journal of infectious diseases, 169(3), 1994, pp. 526-531
To assess long-term nosocomial transmission, trends in antibiotic resi
stance, and expression of potential virulence factors, 86 randomly sel
ected Staphylococcus epidermidis bloodstream isolates obtained from 80
patients in a neonatal intensive care unit (NICU) over a 10-year peri
od were studied. Pulsed-field gel electrophoresis (PFGE) analysis of S
maI-digested whole chromosomal DNA revealed distinctive banding patter
ns that persisted in the NICU overlong periods. Pattern A included 22
isolates (26%) obtained during 1983-1990, and pattern B included 24 is
olates (28%) from 1983 to 1991. All 10 isolates examined in 1984 fell
into one df these two patterns. Isolates with either pattern expressed
polysaccharide/adhesin (PSA) and slime; 90% and 87% were resistant to
oxacillin and gentamicin, respectively, with no trends over time. The
se findings suggest that distinct clones of S. epidermidis can become
endemic in NICUs over periods as long as a decade and that nosocomial
transmission plays an important role in neonatal S. epidermidis bacter
emia.