Now you see it… now you don't

A 52-year-old female presented with a 6 month history of left iliac fossa pain and alteration of bowel habit. She was rather overweight but examination was otherwise unremarkable. A blood count revealed that she was anaemic with a haemoglobin level of 10.1 g d1−1. A barium enema was requested. Two strictures in the mid-transverse colon were demonstrated (Figs 1 & 2). These appearances were unchanged by intravenous administration of Buscopan 20 mg (hyoscine butylbromide). What is your differential diagnosis? These are long strictures affecting adjacent segments of an area of distorted bowel with an abrupt cut-off between normal and abnormal bowel. In some views there appears to be shouldering (Fig. 2). The lumen is circumferentially narrowed and there is a normally distended segment of bowel between the strictures.