TABLE 3.
Identification results obtained with algorithm for presumptive identification of gram-negative bacilli and pigment reaction on CHROMagar Orientation medium
| Organism | Total no. of isolates | No. (%) of isolates with described color | Description of pigment on CHROMagar Orientation medium | No. of isolates
|
|
|---|---|---|---|---|---|
| Correctly identified (with Crystal E/NF system) | Not identified | ||||
| Acinetobacter baumannii | 4 | 4 | White (nontransparent, mucoid) | 4 (4) | |
| Acinetobacter lwoffii | 1 | 1 | White (nontransparent) | 1 (1) | |
| Citrobacter amalonaticus | 1 | 1 | Light blue with diffuse edges | 1 | |
| Citrobacter diversus | 4 | 3 | Metallic blue with diffuse edges | 3 | |
| Citrobacter diversus | 1 | Metallic blue with pinkish border | 1 | ||
| Citrobacter freundii | 13 | 11 (84.6) | Metallic blue interior with pinkish border | 11 | |
| Citrobacter freundii | 2 (15.4) | Metallic blue with no halo | 2 | ||
| Enterobacter aerogenes | 2 | 2 | Metallic blue with no halo | 2 | |
| Enterobacter agglomerans | 1 | 1 | Metallic blue with no halo | 1 | |
| Enterobacter cloacae | 37 | 28 (75.7) | Metallic bluish purple with no halo | 27 | |
| Enterobacter cloacae | 9 (24.3) | Metallic bluish purple with purple-to-pink halo around periphery | 9 | ||
| Escherichia coli | 220 | 218 (99.1) | Pinkish to red | 218 | |
| Escherichia coli | 1 (0.5) | Clear (whitish) | 1 (1) | ||
| Escherichia coli | 1 (0.5) | Blue interior with pink halo (diffuse) | 1 (1) | ||
| Klebsiella oxytoca | 23 | 18 (78.3) | Metallic blue with no pink halo | 18 | |
| Klebsiella oxytoca | 5 (21.7) | Metallic blue with slight pink halo around periphery | 5 | ||
| Klebsiella pneumoniae | 63 | 60 (95.2) | Metallic blue with no pink halo | 59 | |
| Klebsiella pneumoniae | 3 (4.8) | Metallic blue with slight pink halo around periphery | 3 | ||
| Morganella morganii | 10 | 10 (100) | Diffuse brown | 10 | |
| Proteus mirabilis | 9 | 9 (100) | Diffuse brown | 9 | |
| Proteus penneri | 1 | 1 | Diffuse brown | 1 | |
| Proteus vulgaris | 2 | 2 | Bluish green with a slight brown background | 2 | |
| Providencia alcalifaciens | 1 | 1 | Diffuse brown | 1 | |
| Providencia rustigiani | 1 | 1 | Diffuse brown | 1 | |
| Providencia stuarii | 1 | 1 | Diffuse brown | 1 | |
| Pseudomonas aeruginosa | 42 | 42 (100) | Transparent yellow to green, diffuse edges | 42 | |
| Salmonella spp. | 15 | 15 (100) | Clear (whitish) | 15 (15) | |
| Serratia marcescens | 19 | 19 (100) | Aqua blue | 19 | |
| Stenotrophomonas maltophilia | 2 | 2 | Clear (whitish) | 2 (2) | |
| Total no. of isolates | 472 | 466 (24) | 6 | ||