TABLE 2.
Frequency and nature of methods used to identify Pseudomonas aeruginosa by the 17 participating clinical microbiology laboratories
| Identification system | No. of laboratories
|
|
|---|---|---|
| Routine usea | Occasional useb | |
| Oxidase activity | 17 | |
| Colony morphology | 17 | |
| Pigmentation | 7 | |
| Growth at 42°C | 11 | |
| Colistin susceptibility | 4c | |
| Previous culture history | 2 | |
| Vitek 1 | 2 | 1 |
| Vitek 2 | 3 | 3 |
| API 20NE | 1d | 9e |
| Fluorescence on centrimide agar | 1 | |
| C390 susceptibility | 1 | 1 |
| Chromogenic agar | 2 | |
| Arginine hydrolysis | 1 | |
| Fatty acid analysis | 1 | |
| Molecular identification | 5 | |
a
Routinely used to identify all potential P. aeruginosa isolates.
b
Occasionally used when isolates lacked typical phenotypic features of P. aeruginosa.
c
CLSI disk diffusion testing was performed in three laboratories, and CLSI agar dilution testing was used by one laboratory.
d
Routine API 20NE use was initiated during the course of the study.
e
Includes one laboratory which routinely used Vitek 2 for all potential isolates and API 20NE testing when atypical isolates arose.