Table 2.
Association of the rlrA islet with antimicrobial resistance
Antibiotic | no. rlrA positive strains/no. resistant isolates (% rlrA positive strains) | no. rlrA positive strains/no. susceptible isolates (% rlrA positive strains) | OR(95% CI)a | p |
Penicillinb | 69/113 (61) | 59/370 (16) | 8.27 (5.17 – 13.22) | < 10-4 |
Erythromycin | 23/48 (48) | 105/435 (24) | 2.89 (1.58 – 5.30) | 0.0004 |
Tetracycline | 16/38 (42) | 112/445 (25) | 2.16 (1.09 – 4.26) | 0.023 |
Chloramphenicol | 5/14 (36) | 123/469 (26) | NSc | |
Co-trimoxazole | 74/106 (70) | 54/377 (14) | 13.83 (8.35 – 22.91) | < 10-4 |
MDRd | 22/42 (52) | 106/441 (44) | 3.48 (1.83 – 6.62) | < 10-4 |
aAn OR of > 1 indicates increased proportion of rlrA positive isolates whereas OR of < 1 indicates decreased proportion of rlrA positive isolates. Only statistically significant results (FDR < 0.05) are presented.
b Both penicillin intermediate and fully resistant isolates were considered resistant for this analysis
cNS – not significant
dMDR – multidrug resistance defined as resistance to at least three different antimicrobial classes considering as resistant to penicillin both intermediate as well as fully resistant isolates