Pathogenesis, diagnosis, and therapy of feline idiopathic megacolon

Scientific advances in the past decade have brought new understandings to the pathogenesis and therapy of feline colonic motility disorders. Epizootiologic studies have shown, for example, that 96% of the documented cases of obstipation are accounted for by idiopathic megacolon (62%), pelvic canal stenosis (23%), nerve injury (6%), or Manx sacral spinal cord deformity (5%). Recent physiologic studies suggest that most of the idiopathic cases result from colonic smooth muscle dysfunction. The latter studies have also provided evidence that colonic prokinetic agents are useful adjunctive therapy in the treatment of constipation. Many cats are now successfully treated with multicomponent therapy (i.e., dietary fiber supplementation, emollient or hyperosmotic laxatives, and colonic prokinetic agents). Those cats who fail to respond to conservative medical management will generally manifest marked clinical improvement with subtotal colectomy.