Dogs with idiopathic hemorrhagic gastroenteritis (HGE) present with acute onset of bloody diarrhea, vomiting, and hemoconcentration. Because type 1 hypersensitivity reaction to food components or endotoxins from such bacteria as Clostridium perfringens and C difficile has been proposed as an inciting cause, antibiotics are often recommended; however, the benefit of their use remains unknown.
This prospective blinded study evaluated the benefit and efficacy of amoxicillin–clavulanic acid in the treatment of dogs with HGE; this antibiotic is often used for these cases because it is broad spectrum, time dependent, and effective against most gram-positive, some gram-negative, and anaerobic bacteria. Sixty dogs with HGE were included in the study; 53 completed it. Dogs were given either amoxicillin–clavulanic acid or a placebo for 7 days. Therapy was otherwise standardized and included fluids, antiemetics, gastric antacids, and dalteparin natrium for DIC prophylaxis. A canine HGE activity index developed to score the dogs included attitude, appetite, vomiting, stool consistency, stool frequency, and dehydration. Dogs were hospitalized for a minimum of 3 days, after which they could be discharged if they had normal activity, were not dehydrated, and had no watery diarrhea. With regard to mortality, hospitalization rate, and severity of clinical signs, no significant difference between the 2 groups was found. The authors concluded that for dogs with aseptic HGE, antibiotics may not affect outcome or recovery time.
Commentary
The rationale behind using antibiotics in dogs with HGE includes decreasing
bacterial translocation from the intestine (the result of mucosal damage) and the potential for an underlying bacterial cause of HGE. However, antibiotics can lead to multidrug resistance and can harm normal bacterial flora in the gut. This study showed that antibiotics may not be warranted in dogs with acute HGE if the underlying cause is not linked to bacterial infection. —Lisa Powell, DVM, DACVECC
