TABLE 2.
Correlation analysis of oprD mutations (noninsertion and frameshift) and IMP resistance in P. aeruginosa
| Mutation type | No. of strains | No. of strains mutated to stop codons (IMP resistance) | Association of oprD-bearing strains without stop codon mutations and drug resistance phenotypesa |
|||
|---|---|---|---|---|---|---|
| No. of strains without stop codon mutations | No. of core/total no. of target mutations | Resistance rates (%) of strains without stop codon mutations | Correlation with resistance | |||
| 1 | 1 | 1 | 0 | – | – | – |
| 2 | 5 | 4 | 1 | 31/31 | 100 (1/1) | |
| 3 | 22 | 11 | 11 | 26/30 | 91 (10/11) | NA |
| 4 | 10 | 0 | 10 | 29/29 | 70 (7/10) | NA |
| 5 | 1 | 1 | 0 | – | – | – |
| 6 | 44 | 39 | 5 | 22/25 | 100 (5/5) | |
| 7 | 37 | 2 | 35 | 24/24 | 88.6 (31/35) | NA |
| 8 | 4 | 3 | 1 | 11/11 | 100 (1/1) | |
| 9 | 13 | 9 | 4 | 10/10 | 25 (1/4) | NA |
| 10 | 14 | 0 | 14 | 9/9 | 64.2 (9/14) | NA |
| 11 | 6 | 6 | 0 | – | – | – |
| 12 | 12 | 6 | 6 | 3/4 | 66.7 (4/6) | NA |
| 13 | 12 | 2 | 10 | 3/3 | 70 (7/10) | NA |
| 14 | 4 | 4 | 0 | – | – | – |
| 15 | 8 | 6 | 2 | 0/1 | 100 (2/2) | |
| 16 | 16 | 0 | 16 | 0/0 | 75 (12/16) | NA |
| Total | 209 | 94 | 115 | – | 78.2 (90/115) | |
a
NA, strains with identical mutation sites exhibited different imipenem-resistant phenotypes, indicating that the mutation type does not correlate with imipenem resistance. –, No strains met the criteria for oprD-bearing strains without stop codon mutations and drug resistance phenotypes.