| Acute small bowel ischemia | Acute colonic ischemia |
| Age varies with etiology of ischemia | 90 percent of patients over age 60 years |
| Acute precipitating cause is typical | Acute precipitating cause is rare |
| Patients appear severely ill | Patients do not appear severely ill |
| Pain is usually severe, tenderness is not prominent early | Mild abdominal pain, tenderness present |
| Bleeding uncommon until very late | Rectal bleeding, bloody diarrhea typical |
| MRA or MDCT angiography may be considered as the initial diagnostic test; angiography is recommended if there is strong clinical suspicion | Colonoscopy is procedure of choice |
