Coagulase-negative staphylococci and micrococci in urinary tract infections.

One hundred catalase-positive, coagulase-negative, Gram-positive cocci isolated in significant numbers from the urine of patients with urinary tract infections, provisionally subdivided by their sensitivity to nonoviocin, were classified according to a slightly model version of Baird-Parker's schemes (1965 and 1972). It appeared that strains of Micrococcus were nearly all of sub-group 3, and that these were important pathogens of young women presenting with urinary infections in general practice. All such strains were resistant to novobiocin. Strains of staphylococcus were heterogeneous, and were found principally in infections arising in hospital, among older prople. Most staphylococci were sensitive to novobiocin. It is suggested that it is easy and sufficiently accurate to separate staphylococci and micrococci isolated from cases of urinary tract infection on the basis of their sensitivity or resistance to novo-biocin. The distinction is useful because of its therapeutic and epidemiological significance.