Table 2.
Analysis of cultured organisms by qPCR and ddPCR
| Organism | No. of isolates with the given results for the following detection methods: |
|||||
|---|---|---|---|---|---|---|
| Culture |
qPCR |
ddPCR |
||||
| Positive | Negative | Positive | Negative | Positive | Negative | |
| Reference MRSA | 16 | 0 | 16 | 0 | 16 | 0 |
| Reference MSSA | 0 | 2 | 0 | 2 | 0 | 2 |
| Clinical MRSA | 60 | 0 | 58 | 2a | 58 | 2a |
| Clinical MSSA | 0 | 12 | 0 | 12 | 0 | 12 |
| Reference non-SA staphylococci | 1b | 9 | 1b | 9 | 1b | 9 |
| Reference strains | ||||||
| Gram-positive | 0 | 17 | 0 | 17 | 0 | 17 |
| Gram-negative | 0 | 6 | 0 | 6 | 0 | 6 |
| Yeast | 0 | 1 | 0 | 1 | 0 | 1 |
a
Strains initially identified microbiologically as MRSA positive for addition to the collection. Repeat testing (catalase and coagulase tests, Cepheid MRSA GeneXpert analysis) indicated that these two samples were MSSA isolates.
b
S. epidermidis ATCC strain known to be mecA positive.