MOLECULAR EPIDEMIOLOGY OF STAPHYLOCOCCUS-AUREUS AND ENTEROCOCCUS-FAECALIS IN ENDOPHTHALMITIS

Genomic DNA fingerprint analysis was performed on 39 Staphylococcus au reus and 28 Enterococcus faecalis endophthalmitis isolates collected f rom multiple clinical centers. Among 21 S. aureus genomic DNA fingerpr int patterns identified, five clonotypes were recovered from multiple unrelated patients and accounted for 58.9% (23 of 39) of the isolates analyzed. Compared with strains having unique genomic DNA fingerprint patterns, the S. aureus clonotypes occurring more than once were more likely to result in visual acuities of 20/200 or worse (P = 0.036 [chi (2) test]). In contrast to the S. aureus isolates, the E. faecalis end ophthalmitis Isolates were a clonally diverse population, enriched for the expression of a known toxin, cytolysin, which is plasmid encoded.