A comparative study of Staphylococcus epidermidis isolates from clinical material and healthy carriers.

A total of 190 Staphylococcus epidermidis isolates from healthy carriers and clinical material were biotyped according to the Baird-Parker scheme, phage typed by a provisional set of 18 typing phages and tested for antimicrobial susceptibility. The majority of the strains from both groups were found to belong to biotype 1. A considerable number of strains were lysed at 100 x RTD by at least one phage. The strains from healthy carriers were distributed in 24 phage types and about half of them were clustered among three major phage types. Nine of the 30 clinical isolates were of the phage type 130/456 and another nine strains were of eight different phage types. The strain 130/456 represented only three per cent of the phage types from healthy carriers. The clinical strains exhibitbd a multiple resistance pattern to 13 antibiotics. Statistically significant was the difference in the resistance to Penicillin, Streptomycin, Carbenicillin, Erythromycin, Lincomycin, Ampicillin and Kanamycin between the groups of strains from clinical material and healthy carriers. No correlation was observed between biotypes, phage types and antimicrobial susceptibility in both groups of the isolates.