Phosphatase-novobiocin-mannose-inhibition test (PNMI-test) for routine identification of the coagulase-negative staphylococcal urinary tract pathogens S. epidermidis and S. saprophyticus.

A modified Kloos/Schleifer-scheme proved to be useful in identifying coagulase-negative staphylococci isolated from urine. S. epidermidis (44.2%) and S. saprophyticus (21.5%) were the most frequent species. Analysis of patients confirmed both species as urinary pathogens. Using an abbreviated scheme of 6 characteristics, S. saprophyticus was mis-classified in 19.5% of cases. A Phosphatase-Novobiocin-Mannose-Inhibition Test (PNMI-Test) together with a high NaCl concentration (10%) in combination with a coagulase test seems to be an acceptable compromise for routine identification of the three most important staphylococcal urinary tract pathogens, S. aureus, S. epidermidis, and S. saprophyticus. The technical and financial expenditure can be reduced considerably, because an extended identification has to be applied only to strains which cannot be identified by the PNMI-Test.