radiation colitis; radiation enteropathy

Etiology

• radiation therapy (ionizing radiation)
• risk factors
  • hypertension
  • diabetes mellitus
  • atherosclerosis
  • chemotherapy
  • > 40 Gy of radiation
  • previous chemotherapy
  • adhesion
  • older age

Pathology

• involves both colon & small bowel
• rectum is most commonly involved
• endothelial cells of small submucosal arterioles are very sensitive to ionizing radiation
• acute disease
  • occurs immediately after radiation
  • mucosa fails to regenerate
  • friability, hyperemia, edema
• subacute, 2-12 months post radiation
  • endothelial swelling, proliferation, fibrinoid degeneration
  • obliterative endarteritis
• chronic
  • fistulas
  • abscesses
  • strictures & bleeding from intestinal mucosal vessels

Laboratory

• endoscopy shows atrophic mucosa with telangiectatic vessels

Radiology

• acute disease: fine serrations of the bowel
• chronic disease: stricture of the rectum

Management

• endoscopic coagulation

More general terms

• enterocolitis
• radiation injury; radiation toxicity