Evaluating synergy between marbofloxacin and gentamicin in Pseudomonas aeruginosa strains isolated from dogs with otitis externa

The aim of this study was to determine antimicrobial susceptibility of Pseudomonas aeruginosa strains to marbofloxacin and gentamicin, and investigate the possible synergistic, additive, indifferent or antagonistic effects between the two agents. P. aeruginosa strains can develop resistance quickly against certain antibiotics if used alone, thus the need emerges to find synergistic combinations. A total of 68 P. aeruginosa strains isolated from dogs were examined. In order to describe interactions between marbofloxacin and gentamicin the checkerboard microdilution method was utilized. The MICs (minimum inhibitory concentrations) for marbofloxacin and gentamicin were in the range 0.25–64 mg/L and 0.25–32 mg/L, respectively. The combination of marbofloxacin and gentamicin was more effective with a MIC range of 0.031–8 mg/L and a MIC90 of 1 mg/L, compared to 16 mg/L for marbofloxacin alone and 8 mg/L for gentamicin alone. The FIC (fractional inhibitory concentration) indices ranged from 0.0945 (pronounced synergy) to 1.0625 (indifference). Synergy between marbofloxacin and gentamicin was found in 33 isolates. The mean FIC index is 0.546, which represents a partial synergistic/additive effect close to the full synergy threshold. In vitro results indicate that marbofloxacin and gentamicin as partially synergistic agents may prove clinically useful in combination therapy against P. aeruginosa infections. Although marbofloxacin is not used in the human practice, the interactions between fluoroquinolones and aminoglycosides may have importance outside the veterinary field

Pênfigo foliáceo canino: estudo retrospectivo de 43 casos clínicos e terapia (2000-2005) Canine Pemphigus foliaceus: a retrospective study of 43 clinical cases and therapy (2000-2005)

No período de agosto de 2000 a julho de 2005 foram atendidos 43 casos de Pênfigo Foliáceo (PF) canino no Serviço de Dermatologia do Hospital Veterinária, Universidade de São Paulo. Com este estudo retrospectivo visou-se atualizar dados referentes à caracterização sexual, definição racial e raça, idade, tipo e topografia lesional, quadro sintomático e resposta aos tratamentos isolados com prednisona e com a associação desta à azatioprina, além de demonstrar o aumento na ocorrência do PF relativamente à série histórica pretérita (1986-2000) do mesmo Serviço.<br>From August 2000 to July 2005 were attended 43 cases of canine Pemphigus foliaceous (PF) by the Dermatology Service of the Veterinary Teaching Hospital, University of São Paulo. The aim of the present study was to update the records referred to sex, breed, age, type and location of the lesions, clinical signs, and response to treatments with prednisone or combination with prednisone and azathioprine, and also to demonstrate the increase of occurrence of PF compared with the former series (1986-2000) observed in the same Service