Toxic megacolon


  • Colonic Dilation ≥6cm
  • Therapy: Fluids, Electrolyte Repletion, Steroids, Antibiotics, Surgical Consultation
  • AVOID anticholingerics, anti-motility agents, opioids


Clinical Features

Differential Diagnosis


Toxic megacolon on KUB
CT with toxic megacolon showing submucosal edema and mucosal enhancement of the ascending and descending colon giving the appearance of the “target sign”.
CT showing is diffuse dilation of the colon with air and fluid levels present. There is diffuse wall thickening and enhancement in the rectosigmoid colon. The descending, transverse, and ascending colon are dilated to as much as 8.5cm. These features are consistent with a diagnosis of toxic megacolon.


  • Obtain blood cultures, stool cultures, C. Diff Toxin
  • If known cause is C. Diff treat with Vancomycin or Metronidazole
  • If known cause is CMV can add Ganciclovir
  • Avoid
    • Anticholinergics, anti-motility agents, opioids which can worsen dilation
    • Sulfasalazine or 5-aminosalicylate (5-ASA) unhelpful
    • Nasogastric (NG) Tube NOT effective in reducing colonic distention


  • Admit

See Also