Chronic inflammatory enteropathies (CIEs) in dogs are currently classified based on response to sequential treatment trials into food-responsive (FREs); antibiotic-responsive (AREs); immunosuppressant-responsive (IREs); and non-responsive enteropathies (NREs). Recent studies have reported that a proportion of NRE dogs ultimately respond to further dietary trials and are subsequently misclassified. The FRE subset among CIEs is therefore probably underestimated. Moreover, alterations in the gut microbiota composition and function (dysbiosis) have been shown to be involved in CIE pathogenesis in recent research on dogs. Metronidazole and other antibiotics that have been used for decades for dogs with AREs have been demonstrated to result in increased antimicrobial resistance and deleterious effects on the gut microbiota. As a consequence, the clinical approach to CIEs has evolved in recent years toward the gradual abandonment of the use of antibiotics and their replacement by other treatments with the aim of restoring a diverse and functional gut microbiota. We propose here to refine the classification of canine CIEs by replacing the AREs category with a microbiota-related modulation-responsive enteropathies (MrMREs) category.

A 12-year-old male neutered domestic shorthair cat underwent rhinoscopy due to inspiratory dyspnoea and stertor. Rhinoscopy showed signs of chronic rhinitis and a multinodular nasopharyngeal mucosa. A marked infiltrate of macrophages that contained intracellular parasitic forms morphologically compatible with Leishmania amastigotes were observed on histopathological examination of nasal and nasopharyngeal biopsies. PCR from nasal tissue was positive for Leishmania infantum DNA, confirming the diagnosis of granulomatous rhinitis secondary to this parasite. Two eyelid nodules were identified 2 weeks later. Fine-needle aspiration revealed Leishmania amastigotes within macrophages and in the background. Allopurinol therapy was started, but 5 days later the cat developed dermatological signs compatible with a cutaneous adverse drug reaction. The drug was discontinued and meglumine antimoniate prescribed. Twenty-five days later, the cat presented with acute kidney injury and meglumine antimoniate was discontinued. Despite clinical improvement after fluid therapy, mild azotaemia persisted. The cat was subsequently treated with nucleotides and active hexose correlated compounds (N-AHCC). Four months later upper respiratory signs were exacerbated. A relapse of granulomatous rhinitis was suspected and miltefosine therapy started. Chronic kidney disease (CKD) worsened during miltefosine treatment, having improved under fluid therapy. Since then, the cat has been treated with N-AHCC and renal diet and at the time of writing shows stable CKD with no recurrence of respiratory signs. This case describes Leishmania infantum as a cause of granulomatous rhinitis in a cat without cutaneous lesions, reporting the alternative use of N-AHCC and miltefosine when allopurinol seemed to have induced a cutaneous rash and there was acute kidney injury (AKI) after meglumine antimoniate therapy.

Background: Hydrolyzed protein diets are commonly used in the first-line approach to the treatment of dogs with naïve-chronic enteropathy (naïve-CE). Objectives: To characterize the responses of naïve-CE dogs transitioned to a hydrolyzed diet and to assess the efficacy of an additional dietary trial in dogs with NRE. Animals: Eighty-one dogs with naïve-CE and 23 dogs with NRE. Methods: Retrospective multicenter cohort study including dogs with CE presented to three referral centers from April 2018 to December 2021. Naïve-CE and NRE cases transitioned to hydrolyzed and alternative diets, respectively, were selected, and medical records were reviewed. Clinical response before and 4 weeks after dietary transitions (with or without concurrent therapeutic adjustments) was assessed based on stool-consistency score or Canine Inflammatory Bowel Disease Activity Index (CIBDAI) total score in naïve and NRE cases, respectively. Results: The transition into a hydrolyzed diet was the only therapeutic change in 20% (16/81). Of these, 88% (14/16) had a decreased stool-consistency score (p < 0.001). From the 23 NRE cases, the transition to an alternative diet was the sole therapeutic adjustment in 70% (16/23). Of these, the total CIBDAI score declined in 69% (11/23; p < 0.001). Conclusions and Clinical Importance: This study supports the need to feed a hydrolyzed diet in naïve CE cases. In cases classified as NRE, an additional transition into an alternative dietary trial seems beneficial.