Table II.
Treatment and outcome for the 7 horses with soft tissue infection
| Case number | Treatment historya | Culture results | Treatment regimena | Outcome |
|---|---|---|---|---|
| 1 | Penicillin and gentamicin | Gram-negative rods and Enterococcus spp. | Amikacin and vancomycin (7.5 mg/kg q12h) for 10 d | Recovered: infection resolved; MCP joint fused |
| 7 | Not recorded | Enterococcus spp. And Escherichia coli isolated from peritoneal fluid and incision site | Amikacin and vancomycin for 5 d; at discharge, therapy changed to TMPS for 14 d | Recovered from infection but euthanized when incision dehisced during unrestricted activity 3 wk after surgery |
| 8 | Not recorded | Staphylococcus aureus, E. coli, Enterobacter cloacae, Pseudomonas aeruginosa, α-hemolytic Streptococcus sp., and Enterococcus spp. Isolated from right forelimb incision; Staphylococcus spp. Susceptible only to vancomycin isolated from left forelimb | Penicillin and gentamicin; culture 7 d later yielded P. aeruginosa and Klebsiella oxytoca from right incision and S. aureus from left incision; on basis of susceptibility results, treatment changed to amikacin and vancomycin for 5 d | Recovered: rapid clinical improvement after therapy with amikacin and vancomycin |
| 9 | Not recorded | S. aureus susceptible only to vancomycin | Surgical debridement; vancomycin for 10 d | Recovered: negative culture 72 h after completion of therapy |
| 10 | Not recorded | Enterococcus spp. Susceptible only to vancomycin | Surgical debridement; vancomycin | Infection resolved but laminitis in opposite limb necessitated euthanasia |
| 14 | Oral TMPS | MRSA | Systemic vancomycin | Recovered: horse raced successfully |
| 15 | Penicillin and gentamicin | Enterococcus faecium susceptible only to vancomycin; E. coli susceptible to amikacin | Systemic vancomycin and amikacin | Recovered: rapid clinical improvement after treatment with amikacin and vancomycin |
a
Unless otherwise stated, dosages were as follows: amikacin, 6.6 mg/kg IV q8h; ampicillin, 15 mg/kg IV q8h; ceftiofur, 2.2 mg/kg IV q12h; erythromycin, 44 mg/kg orally q6h; gentamicin, 2.2 mg/kg IV q8h; potassium penicillin G, 22 000 IU/kg IV q6h; rifampin, 2.5 mg/kg orally q6h; TMPS, 15 mg/kg orally q12h; vancomycin, 7.5 mg/kg IV q8h (infused over 30 min)
MRSA — methicillin-resistant S. aureus