Focal intestinal lipogranulomatous lymphangitis in 10 dogs.

ABSTRACT

OBJECTIVES: To describe the clinical and pathological features of canine focal lipogranulomatous lymphangitis, to evaluate its underlying infectious cause and to compare it with human Crohn's disease. METHODS: Retrospective review of case records with a histopathological diagnosis of focal lipogranulomatous lymphangitis. Bacterial and fungal colonisation was evaluated using fluorescence in situ hybridisation and histochemical staining, respectively. A comparison with Crohn's disease was performed by a human pathologist. RESULTS: Ten dogs were evaluated. The historical complaints were predominantly chronic diarrhoea (10/10) and vomiting (5/10). The biochemical abnormalities included hypoalbuminaemia (6/10) and hypocobalaminaemia (4/6). Abdominal sonography revealed a thickened distal ileum±ileocolic junction. Colonoscopy showed a swollen caecal ostium and oedematous caecum in 7/10 dogs. A stenotic ileo-colic opening prevented endoscopic intubation in all dogs. Histology from the resected lesions revealed granulomatous inflammation involving the muscularis and serosa. Fluorescence in situ hybridization demonstrated invasive bacteria in 2/10 dogs. Post-resection, all dogs received metronidazole and tapering immunosuppressive doses of prednisolone. Remission (median 17 months) was achieved in 8/10 dogs. CLINICAL SIGNIFICANCE: Focal lipogranulomatous lymphangitis is a rare and severe form of canine inflammatory bowel disease with preferential localisation to the ileum and the ileocolic junction. An underlying infectious aetiology was not identified.