modified trehalose-mannitol-phosphatase agar for differentiation of staphylococcus epidermidis and staphylococcus saprophytics from other coagulase-negative staphylococci

Trehalose-mannitol agar was used instead of trehalose-mannitol phosphatase agar for differentiating of staphylococcus epidermidis and Staphylococcus saprophyticus from other coagulase negative staphylococci. Staphylococcus epidermidis showed a sensitivity of 100%, specificity of 89.6% and a positive predictive value of 95.7%. Addition of 5mu g novobiocin disk to the medium differentiates staphylococcus saprophyticus with a sensitivity of 100%, specificity of 97% and a positive predictive value of 86.2%. Trehalose-mannitol- agar is considered as a simple and less expensive medium that yields reliable results