Megacolon in the elderly. Ischemic or inflammatory?

Area of Science:

• Gastroenterology
• Colorectal Surgery

Background:

• Ischemic colitis is typically described in transient, strictured, and gangrenous forms.
• Elderly patients may present with a distinct fourth form of ischemic colitis.

Observation:

• This fourth form is characterized by acute abdomen, massive colonic dilatation, and systemic toxicity.
• Bloody diarrhea can precede colonic dilatation.
• The rectum is typically uninvolved in this condition.

Findings:

• Ischemia is a critical consideration in elderly patients with segmental colonic dilatation, especially after a "low flow state."
• Barium enema can confirm segmental involvement and subsequent stricture formation.
• Three cases of ischemic megacolon are presented, with preoperative diagnosis in only one patient.

Implications:

• Ischemic megacolon in the elderly has a more abrupt onset and fulminant course compared to ulcerative colitis.
• Recovered patients exhibit a lower relapse rate than young ulcerative colitis patients.
• Surgical management should prioritize rectal preservation; loop ileostomy and decompressive colostomy are effective temporizing measures.