Table 6.
Summary of the pathotype, antimicrobial resistance patterns, QRDR mutation and presence of qnr resistance genes for the 18 E. coli isolates selected for their resistance to fluoroquinolones of second (pefloxacin) and third (levofloxacin) generation.
| Strains ID | MDR phenotypea | Diffusion discb | QRDR mutation | PMQR genes | Other resistance genes | E. coli typec | ||
|---|---|---|---|---|---|---|---|---|
| LEV | PEF | →GyrA | →ParC | |||||
| 16C | AmCbClSxtLevPef | R | R | S83→L, D87→N | S80→I | qnrA | aph3(strA), blaTEM, class 1 integron | Incomplete ExPEC |
| 18A | AmCfCtxCroLevPefStx | R | R | S83→L, D87→N | S80→I | aac-(6′)-lb-cr, qnrS | aph3(strA), aph6(strB), blaTEM, tet(B), tet(M) | InPEC |
| 18C | AmCfCtxCroLevPefStx | R | R | S83→L | None | aac-(6′)-lb-cr, qnrS | aph3(strA), aph6(strB), blaTEM, dhfrVII, tet(B) | InPEC |
| 17A | AmGLevSxt | R | S | S83→L, D87→N | S80→I | None | blaTEM, aac(3)-IIa(aacC2), aph3(strA), mphA, sulII, class 1 and 2 integron | InPEC |
| 17D | AmCbGLev | R | S | S83→L, D87→N | S80→I | None | aph3(strA), blaTEM, aac(3)-IIa(aacC2), mphA, sulI, sulII, tet(B), class 1 integron | InPEC |
| 17E | AmCbLev | R | S | None | None | None | aph3(strA), blaTEM, dhfrXII, sulII, tet(A) | Incomplete ExPEC |
| 24A | AmCbClCfPefSxt | S | R | S83→L, D87→N | S80→I | qnrA | aph3(strA), blaTEM, dhfrXII, mphA, sulII, tet(B), class 1 integron | Commensal |
| 16D | AmCbClPefSxt | S | R | S83→L, D87→N | S80→I | qnrA | aph3(strA), blaPSE, blaTEM, catI, dhfrXII, mphA, tet(A), tet(B), sulI, sulII, class 1 and 2 integron | Commensal |
| 24C | AmCbClPefSxt | S | R | S83→L, D87→N | S80→I | None | cmIAI, dhfrXII, class 1 integron | Commensal |
| 24E | AmCbClPefSxt | S | R | S83→L, D87→N | S80→I | None | dhfrXII, cmlAI. | Commensal |
| 1A | CfNfPef | S | R | S83→L, D87→N | None | qnrS | aph3(strA) | Commensal |
| 22E | Pef | S | R | None | None | qnrS | ND | Commensal |
| 3A | AmClStxPef | S | I | None | None | qnrA | aph3(strA), blaPSE, dhfrVII, sulII, tet(A), class 2 integron | InPEC |
| 2E | AmClStxPef | S | I | S83→L, D87→N | None | None | Class 1 and 2 integron. | Commensal |
| 29A | AmCbNfSxtPef | S | I | None | S80→I | qnrA, qnrB | blaPSE, dhfrXII, class 1 integron | InPEC |
| 20A | AmPef | S | I | None | None | qnrB, qnrS | aph3(strA), blaTEM | Commensal |
| 29E | AmCfCbSxtPef | S | I | None | None | qnrS | aadA (1), blaTEM, dhfrI, sulI, class 1and 2 integron, transposon Tn21 | InPEC |
| 25A | AmCbPef | S | I | S83→L | None | qnrB, qnrS | Transposon Tn21 | Commensal |
a
Multi-drug resistance (MDR) phenotype, Am, ampicillin; Cb, carbenicillin; Cl, chloramphenicol; Pef, pefloxacin; Lev, levofloxacin; Sxt, trimethoprim-sulfamethoxazole; G, gentamicin; Net, netilmicin; Ak, amikacin; Cf, Cephalotine; Ctx, cephatoxim; Cro, ceftriaxone; Nf, nitrofuratoin. ND, not determined.
b
R, resistant; I, intermediate resistance; S, susceptible.
c
InPEC, intestinal E. coli; ExPEC, extraintestinal E. coli.