Idiopathic anomalous congenital band causing small intestinal obstruction in a 5-month-old dog.

A 5-month-old, intact male, yellow Labrador retriever was presented with a 24-hour history of anorexia and vomiting. Abdominal imaging revealed the presence of a mechanical obstruction in the jejunum and peritoneal effusion. Cytologic evaluation and culture of the effusion prior to surgery identified a suppurative exudate with bacteria consistent with septic peritonitis and suspected to be related to the intestinal lesion. An exploratory laparotomy was performed, and a segment of jejunum was circumferentially severely constricted by an off-white, fibrous band of tissue. Resection and anastomosis of the strangulated segment of jejunum and excision of the constricting band provided resolution of the clinical signs. The dog made a complete recovery. Histologic evaluation revealed the band to be composed of fibrovascular and smooth muscle tissue, consistent with an idiopathic anomalous congenital band. No other gastrointestinal lesions were observed, either grossly at surgery or histologically in the resected segment of intestine. To our knowledge, a similar structure has not been reported in the veterinary literature. Key clinical message: Developmental abnormalities should be included in the differential list for younger patients with signs suggestive of gastrointestinal obstruction.