TABLE 2.
Number and nature of false-positive S. aureus strains identified using CSAM alone, CSAM plus the Pastorex Staph Plus test, and CSAM plus the Staphychrom coagulase test
| Strain(s) | No. of strains with false-positive S. aureus identification usinga:
|
||
|---|---|---|---|
| CSAMb | CSAMb + Pastorex Staph Plus test | CSAMb + Staphychrom coagulase test | |
| Micrococcus spp. | 2 | 0 | 0 |
| Staphylococcus epidermidis | 3 | 0 | 0 |
| Staphylococcus simulans | 3c | 3c | 0 |
| Staphylococcus intermedius | 1 | 1 | 0 |
| Staphylococcus warneri | 1 | 1 | 0 |
| Staphylococcus schleiferi | 1 | 1 | 0 |
| Other coagulase-negative Staphylococcus spp. | 4 | 0 | 0 |
| Total | 15 | 6 | 0 |
a
Specificities were the following: for CSAM, 97%; for CSAM + Pastorex Staph Plus test, 98.8%; for CSAM + Staphychrom coagulase test, 100%.
b
Mauve colony and suggestive Gram staining, but not an S. aureus strain.
c
These three strains were isolated from different specimens from the same patient.