Circumferential mural bands in the small intestine causing simple obstructive colic: a case series

REASONS FOR PERFORMING STUDY: Circumferential mural band (CMB) in the small intestine is an emerging condition in Ireland. The clinical presentation is a simple obstruction of the small intestine of unknown aetiology. HYPOTHESIS: Horses affected with CMB in the small intestine have a good prognosis following surgical decompression into the caecum. METHODS: A retrospective study was carried out and 28 cases identified from 559 colic surgeries performed over a 5.5 year period. An exploratory celiotomy was performed in every case. A simple obstruction at the mid or distal jejunum was identified caused by a CMB, which was multiple in some cases. All of the horses except 2 had undergone a regular anthelmintic programme. RESULTS: Manual decompression of the small intestine into the caecum resulted in resolution of the simple jejunal obstruction. A constricted segment of small intestine was resected in one case, as the degree of constriction was severe. A full thickness biopsy was taken from another case. Histopathology was performed on both samples. All horses recovered from surgery and were discharged from the hospital 7-32 days post operatively. Short-term complications were observed. Survival rate was 100% at long-term follow-up. Histopathology showed inflammatory infiltration in the submucosa, muscularis and serosa with eosinophils predominating. Parasites were not detected. CONCLUSION AND POTENTIAL RELEVANCE: Small intestine circumferential mural bands have a good prognosis after surgical decompression of the small intestine into the caecum.