Clostridium perfringens e Clostridium difficile em relação a outros enteropatógenos em cães diarreicos

Abstract

The aim of this study was to evaluate the occurrence of Clostridium perfringens and Clostridium difficile infection compared to other enteropathogens in dogs, such as parvovirus, coronavirus, rotavirus, Giardia spp., Salmonella spp. and Escherichia coli. A total of 154 fecal samples were collected, 92 from diarrheic dogs, from veterinary hospitals, and 62 from apparently healthy dogs (control group). The dogs were divided into four age groups: 0-6 months (passive immunity), 7-12 months (establishment of active immunity), 13-60 months (adults) and older than 61 months (seniors). After isolation of C. perfringens in selective media, the presences of the following genes were evaluated by PCR: cpa, cpb, etx, iap, cpb2, cpe, netB, netE, netF e netG. The isolated strains of C. difficile were ribotyped and the presences of the following genes were evaluated by PCR: tcdA, tcdB, tpi e cdtB. Two ELISAs were used to detect A/B toxins and enterotoxin in stool samples that were positive for isolation of C. difficile and C. perfringens strains positive for the gene cpe, respectively. The differential diagnosis of other enteropathogens included Salmonella spp. by isolation; isolation of E. coli followed by PCR; and immunochromatography tests to detect canine parvovirus type 2 (CPV), canine coronavirus (CCV), canine rotavirus (CRV) and Giardia spp. Approximately in 52,1% of diarrheic animals and 50% of healthy dogs were negative for all enteropathogens tested. There was a positive association between the presence of CPE gene (cpe) from C. perfringens and the occurrence of diarrhea (p=0.006), the CPE toxin was also detected in half of these fecal samples. The gene encoding the recently described NetE toxin (netE) was found in 70% of C. perfringens strains positive for CPE, all from adult dogs (aging more than 12 months). The frequency of isolation of C. difficile toxigenic strains increased in dogs over the age of 60 months, and the ribotype 014/020 was the most frequent in this study. Among the co-infections detected, stand out the first description of C. perfringens type A cpe+ and netE+ netF + and C. difficile coinfection in two dogs. This study suggests that C. difficile and C. perfringens are important enteropathogens in dogs and can occur in co-infections with other microorganisms, including Clostridium species.