Table 2.
Distribution of antimicrobial and multidrug resistance among S. pseudintermedius isolated from canine specimens submitted to a veterinary diagnostic laboratory in Tennessee, USA (2006–2017)
| 2006–2008 | 2009–2011 | 2012–2014 | 2015–2017 | Total | |
|---|---|---|---|---|---|
| Aminoglycosides | |||||
| Gentamicin | 19.3 (242/1256) | 31.7 (482/1523) | 29.2 (297/1016) | 27.4 (241/881) | 27.0 (1262/4676)*** |
| β-lactams | |||||
| Ampicillin | 84.7 (1020/1204) | 83.9 (1277/1523) | 84.5 (1566/1854) | 84.2 (1499/1781) | 84.3 (5362/6362) |
| Cefoxitin | 21.7 (272/1251) | 19.9 (301/1510) | 19.0 (353/1855) | 22.4 (396/1768) | 20.7 (1322/6384) |
| Oxacillin | 32.6 (411/1259) | 36.9 (559/1514) | 34.3 (638/1861) | 34.8 (622/1790) | 34.7 (2230/6424) |
| Fluoroquinolones | |||||
| Marbofloxacin | 31 (385/1244) | 30.1 (453/1504) | 28.3 (523/1848) | 29.1 (412/1417) | 29.5 (1773/6013) |
| Folate inhibitors | |||||
| TMSa | 42.1 (529/1258) | 42.7 (649/1521) | 42.5 (791/1863) | 49.5 (894/1805) | 44.4 (2863/6447)*** |
| Lincosamides | |||||
| Clindamycin | 38.9 (489/1256) | 40.3 (613/1522) | 39.1 (727/1859) | 38.2 (688/1801) | 39.1 (2517/6438) |
| Macrolides | |||||
| Erythromycin | 38.4 (483/1257) | 39.7 (604/1522) | 39.1 (726/1858) | 38.0 (685/1802) | 38.8 (2498/6439) |
| Phenicols | |||||
| Chloramphenicol | 2.5 (31/1258) | 3.3 (50/1523) | 5.8 (107/1862) | 8.7 (157/1805) | 5.4 (345/6448)*** |
| Tetracyclines | |||||
| Tetracycline | 52.4 (659/1257) | 50.1 (762/1521) | 45.9 (855/1862) | 44.8 (797/1780) | 47.9 (3073/6420)*** |
| AMRb | 87.1 (1096/1259) | 86.8 (1322/1523) | 86.5 (1611/1863) | 86.7 (1567/1808) | 86.7 (5596/6453) |
| MDRc | 44.2 (557/1259) | 45.8 (697/1523) | 45.1 (840/1863) | 46.4 (839/1808) | 45.5 (2933/6453) |
| MRSPd | 26.1 (300/1148) | 32.5 (479/1473) | 31.7 (585/1844) | 31.5 (544/1730) | 30.8 (1908/6195)* |
aTrimethoprim/sulfamethoxazole
bAntimicrobial resistance
cMultidrug resistance
dMethicillin-resistant S. pseudintermedius, based on oxacillin disk diffusion testing confirmed with positive mecA PCR
*p < 0.05, **p < 0.01, ***p < 0.0001 for Cochran-Armitage trend test