Crohn's disease presenting as bladder mass

A previously well 15-year-old boy presented with a month-long history of bloody diarrhoea, weight loss, low albumin and coexistent dysuria. An ultrasound of the abdomen showed appearances suggestive of terminal ileal thickening and mesenteric oedema. There was also an irregular bladder wall mass measuring 1.5 cm in maximal thickness (figure 1). An MRI showed appearances consistent with Crohn's disease, with marked inflammatory change in the distal small bowel and proximal …