Table 4. Colistin MIC (by broth microdilution method) of all multidrug-resistant non-fermenting Gram-negative bacilli isolated.
MIC, minimum inhibitory concentration
| Isolates | Total number of isolates | Colistin MIC ≤ 2 (intermediate) | Colistin MIC ≥ 4 (resistant) |
| Acinetobacter haemolyticus | 34 | 32 (94.1%) | 2 (5.8%) |
| Acinetobacter baumannii | 174 | 170 (97.7%) | 4 (2.35%) |
| Acinetobacter lwoffii | 84 | 84 (100%) | - |
| Alcaligenes faecalis | 4 | 4 (100%) | - |
| Burkholderia cepacia complex | 7 | Intrinsically resistant | Intrinsically resistant |
| Chryseobacterium indologenes | 1 | - | 1 (100%) |
| Elizabethkingia meningoseptica | 5 | 1 (20%) | 4 (80%) |
| Pseudomonas aeruginosa | 384 | 365 (95%) | 19 (5.2%) |
| Pseudomonas fluorescens | 19 | 19 (100%) | - |
| Pseudomonas luteola | 4 | 4 (100%) | - |
| Pseudomonas putida | 7 | 7 (100%) | - |
| Pseudomonas stutzeri | 4 | 4 (100%) | - |
| Ralstonia pickettii | 3 | 1 (34%) | 2 (66.6%) |
| Sphingomonas | 2 | 2 (100%) | - |
| Stenotrophomonas maltophilia | 11 | 10 (90.9%) | 1 (10%) |