Acute Colonic Pseudo-Obstruction Secondary to Renal Calculus: A Case Report and Review of Pathophysiology.

Acute colonic pseudo-obstruction (ACPO) is obstruction of the large bowel without a mechanical cause. The exact mechanism remains incompletely understood but is thought to result from disruption to the autonomic regulation of the colon, typically in the context of hospitalized patients with medical illness, precipitating medications, or recent surgical intervention. This paper presents an unusual case of ACPO in an ambulatory patient with a recently passed renal calculus, explores the anatomy and physiology underlying the autonomic dysfunction theory of ACPO pathogenesis in the context of the case, and provides a 3D reconstruction of the patient's CT to illustrate the abrupt caliber change at the splenic flexure characteristic of ACPO.