COMPARATIVE-EVALUATION OF USE OF CNA, FNBA, FNBB, AND HLB FOR GENOMICFINGERPRINTING IN THE EPIDEMIOLOGIC TYPING OF STAPHYLOCOCCUS-AUREUS

We used a genomic fingerprinting protocol to characterize 59 Staphyloc occus aureus strains and a single S. intermedius isolate, all of which were previously typed by 13 different methods (F. C. Tenover ct al., J. Clin, Microbiol. 32:407-415, 1994), These 60 strains were divided i nto three groups of 20 Strains each, with each group including interna l controls, Two of the three groups (groups SB and SC) included 29 str ains from four relatively well-defined outbreaks, The epidemiological relationships of the strains in the third group (group SA) were unclea r, Fingerprints were established by Southern Plotting with HaeIII-dige sted genomic DNA and a probe mixture consisting of DNA fragments corre sponding to the S. aureus collagen adhesin (cna), fibronectin-binding protein (fnbA and fnbB), and beta-toxin (hlb) genes, An unambiguous fi ngerprint was obtained for all S. aureus isolates. No hybridization si gnal was observed with S. intermedius. Twenty-seven of the 29 related strains in the SE and SC groups were correctly identified as belonging to one of the four epidemiologically related groups, Our protocol was less successful with respect to the exclusion of unrelated strains, S pecifically, only 6 of 11 unrelated strains in the SE and SC groups ha d a fingerprint that was distinct by comparison to the fingerprints of the outbreak strains. Nevertheless, our protocol was relatively accur ate by comparison to the accuracies of the other methods and was one o f only six methods that accurately identified all of the repetitive st rains included as internal controls.