Volume 16, Number 1—January 2010
Research
Methicillin-Resistant and -Susceptible Staphylococcus aureus Infections in Dogs
, Michelle Traverse, Kathy C. Tater, David L. Pearl, and J. Scott Weese
Table 3
Univariable analysis of infection site, duration of hospitalization, and medical and surgical risk factors for MRSA versus MSSA infections in dogs, United States and Canada, 2001–2007*
| Variable | MRSA, no. (%) dogs, n = 40 | MSSA, no. (%) dogs, n = 80† | Odds ratio (95% CI) | p value‡ |
|---|---|---|---|---|
| Site of infection | ||||
| Skin | 19 (47.5) | 38/78 (48.7) | Ref | |
| Ear | 5 (12.5) | 11/78 (14.1) | 0.89 (0.21–3.28) | 1.00 |
| Skeletal§ | 7 (17.5) | 6/78 (7.7) | 2.69 (0.53–17.96) | 0.23 |
| Urinary¶ | 3 (7.5) | 11/78 (14.1) | 0.37 (0.03–2.20) | 0.29 |
| Other# |
6 (15.0) |
12/78 (15.4) |
1.06 (0.24–4.14) |
1.00 |
| Duration of hospitalization | ||||
| Short (<2 d) | 25 (62.5) | 57 (71.3) | Ref | |
| Medium (3–7 d) | 11 (27.5) | 19 (23.8) | 1.59 (0.52–4.94) | 0.45 |
| Long (>7 d) |
4 (10.0) |
4 (5.0) |
2.70 (0.43–17.49) |
0.23 |
| Intravenous catheterization** | ||||
| No | 21 (52.5) | 58 (72.5) | Ref | |
| Yes |
19 (47.5) |
22 (27.5) |
3.27 (1.14–10.65) |
0.02 |
| Surgery** | ||||
| No | 25 (62.5) | 58 (72.5) | Ref | |
| Yes |
15 (37.5) |
22 (27.5) |
1.61 (0.65–4.09) |
0.29 |
| Urinary catheterization** | ||||
| No | 36 (90.0) | 77 (96.3) | Ref | |
| Yes | 4 (10.0) | 3 (3.8) | 6.00 (0.48–314.98) | 0.11 |
*MRSA, methicillin-resistant Staphylococcus aureus; MSSA, methicillin-susceptible Staphylococcus aureus; CI, confidence interval; Ref, referent category. Dogs with MRSA (case-patients) and MSSA (controls) infections were matched for veterinary referral hospital and date of admission.
†Except as indicated.
‡Score method for estimating p values does not assume a symmetrical distribution for discrete data. p<0.05 was considered significant.
§Specimens were from internal joint surface, joint fluid, intramedullary pin, and orthopedic implant.
¶Specimens were urine, urinary calculus, urinary catheter, and the wall of the urinary bladder.
#Specimens were abdominal and thoracic fluids, blood, oral cavity swabs, lymph nodes, vaginal swabs, transtracheal wash fluid, and milk.
**Procedures performed before infection occurred.