Ischemic colitis

Background

Intestinal Ischemic Disorder Types

• Ischemic colitis
  • Accounts for 80-85% of intestinal ischemia
  • Due to non-occlusive disease with decreased blood flow to the colon.
  • Causes decreased perfusion leading to sub-mucosal or mucosal ischemia only.
  • Typical to the "watershed areas" of the colon (Splenic flexure or Sigmoid)

• Acute mesenteric ischemia
  • Due to complete occlusion of mesenteric vessels
  • Complete transmural ischemia

• Mesenteric venous thrombosis
• Chronic mesenteric ischemia ("intestinal angina")

Clinical Features

• Consider ischemic colitis as the possible cause of acute-onset abdominal pain with rectal bleeding in patients age 50 and older with cardiovascular morbidities.
• Frequently presents with bloody diarrhea and may have mucous as well and abdominal pain
• Risk Factors:
  • Constipation (increased intraluminal pressure compresses vessels)
  • IBS
  • Vascular risk factors increase risk of ischemic colitis
  • Risk double in patients with COPD.
  • Females > Males
• Can be precipitated by any illness that decreases flow:
  • Hypovolemia
  • Blood loss
  • Dialysis
  • Anaphylaxis
  • Pancreatitis
• Can be precipitated by drugs:
  • NSAIDs
  • Cocaine
  • Anti-Hypertensives
  • Diuretics
  • Digitalis
  • Carboplatin-Paclitaxel
  • Vasopressors
  • Pseudoephedrine
  • Triptans
  • Interferon-Ribavirin

Differential Diagnosis

Colitis

• Infectious colitis
• Ischemic colitis
• Ulcerative colitis
• CMV colitis
• Crohn's colitis
• Toxic colitis (antineoplastic agents)
• Pseudomembranous colitis
• Fibrosing colonopathy (Cystic fibrosis)

Diffuse Abdominal pain

• Abdominal aortic aneurysm
  • Aortocaval fistula
• Acute gastroenteritis
• Aortoenteric fisulta
• Appendicitis (early)
• Bowel obstruction
  • Large bowel obstruction
    • Ogilvie's syndrome
  • Small bowel obstruction
  • Malignant bowel obstruction
• Bowel perforation
• Diabetic ketoacidosis
• Gastroparesis
• Hernia
• Hypercalcemia
• Inflammatory bowel disease
• Mesenteric ischemia
  • Mesenteric vein thrombosis
• Pancreatitis
• Peritonitis
• Sickle cell crisis
• Spontaneous bacterial peritonitis
• Volvulus

Evaluation

Workup

• CBC to evaluate for quantity of blood loss
• CMP to evaluate for acute renal injury
• CT Abdomen and Pelvis with Contrast to evaluate for intestinal inflammation.
• May consider CTA to rule out mesenteric ischemia, but will rarely show large vessel occlusion.

Diagnosis

• CT will show colitis. Ischemic colitis most likely when found in splenic flexure or sigmoid colon. Ischemic colitis unlikely for colitis that localizes to other areas

Management

• Antibiotics, if the patient has any of the factors associated with severe disease.
• Emergent surgical consultation for:
  • Peritoneal signs
  • Pneumatosis coli
  • Portal venous gas
  • Pan-colonic distribution, or
  • Isolated right-colon ischemia on imaging
• Improved hydration
• Avoid NSAIDs
• Bowel rest with clear liquid diet

Disposition

• Admit patient with more severe symptoms. Pain uncontrolled, large volume blood loss, unable to tolerate PO.
• Most patients can be discharged
• Need follow up colonoscopy in months to ensure no underlying etiology.
• Ensure future workup for younger patients
  • More likely to have underlying vasculitis or other cause.

See Also

• Colitis
• Mesenteric ischemia

External Links

• Shannon Thompson. Ischemic Colitis: ED Presentations, Evaluation, and Management emDOCs.net

References

Washington C, Carmichael JC. Management of ischemic colitis. Clin Colon Rectal Surg. 2012 Dec;25(4):228-35. doi: 10.1055/s-0032-1329534. PMID: 24294125; PMCID: PMC3577613.