Proposal for rational antibacterial use in the diagnosis and treatment of dogs with chronic diarrhoea

Chronic diarrhoea is a frequent complaint in canine practice, and the diagnostic path is often characterized by numerous diagnostic tests and stepwise empirical treatments, often performed prior to gastrointestinal endoscopy/mucosal biopsies. These include dietary interventions (novel protein/hydrolysed protein diet), parasiticides and, still, in many cases, antibacterials. In order to decrease the risk of multiple potentially detrimental consequences for both the individual patient (antimicrobial resistance, long-term disruption of intestinal bacterial populations, potential worsening of gastrointestinal signs) and the general public, we advocate the use of antibacterials only after histopathologic evaluation of gastrointestinal biopsies, or at least after that any other therapeutic trial (e.g. diet/pre-probiotics, anti-inflammatory drugs) has been shown to be unsuccessful, in those cases in which endoscopy is not possible. They should be reserved, after appropriate dietary trials, for those canine chronic diarrhoeic patients with signs of true primary infection (signs of systemic inflammatory response syndrome or evidence of adherent-invasive bacteria) that justify antibacterial usage. In the present article we therefore discourage the empirical use of antibacterials when managing dogs with suspected chronic enteropathy.