[Differentiation of coagulase negative staphylococci from significant bacteriuria]

According to our experience in identifying coagulase negative staphylococci (CNS) a modified Kloos-Schleifer-scheme proved useful in species identification. Of 595 urine isolates from cases with significant bacteriuria tested 89.5% could be identified. For routine identification on the one hand the Kloos-Schleifer-scheme is only practical by using commercial identification systems, on the other hand applying an abbreviated scheme species identification is unsatisfactory. As an alternative for identification of CNS in clinical microbiology the Phosphatase-Novobiocin-Mannose-Inhibition-Test (PNMI-Test) is presented. This test in combination with a coagulase test proved suitable to identify the three most important staphylococcal species S. aureus, S epidermidis, and S. saprophyticus and seems to be an acceptable compromise in the bacteriological routine laboratory. For extended species identification of CNS the Kloos-Schleifer-scheme should not be reduced but this identification should be reserved to special laboratories.