Mesenteric vein thrombosis
A rare (< 5% of all cases) subset of mesenteric ischemia that has a high rate of mortality approaching 50%. Risk factors include intrabdominal inflammation and hypercoaguability.
Depends on subtype and disease can exist along a continuum.
- acute-expect typical features such as severe abdominal pain that is out of proportion to exam findings. Rebound and guarding may occur. Time course usually over days.
- subacute- abdominal pain can be vague and symptoms may be insidious over a period of days to weeks.
- chronic- patients usually are asymptomatic and thrombosis is usually found on imaging incidentally. Some patients may have post prandial colicky abdominal pain that resolves.
- Abdominal aortic aneurysm
- Acute gastroenteritis
- Aortoenteric fisulta
- Appendicitis (early)
- Bowel obstruction
- Bowel perforation
- Diabetic ketoacidosis
- Inflammatory bowel disease
- Mesenteric ischemia
- Sickle cell crisis
- Spontaneous bacterial peritonitis
- Labs- CBC, CMP, Lipase, UA, HCG(when applicable), Lactate, Coags.
- from the ED stand point a multiphase contrast CT is the most accurate and timely.(Non-contrast, arterial phase, and venous phase).
- oral contrast can help dilineate bowel thickness.
- Magnetic resonance venography is another option if testing is non-diagnostic.
- meseteric vein filing defect, bowel thickening, bowel hypoattenuation, bowel enhancement, pneumatosis, potential ascites. 
- labs, other forms of imaging, and physical exam do not have high enough sensitivity to reliably exclude this diagnosis.
- Harnik IG, Brandt LJ. Mesenteric venous thrombosis. Vasc Med. 2010 Oct;15(5):407-18. doi: 10.1177/1358863X10379673. PMID: 20926500.
- American Journal of Roentgenology. 2009;192: 408-416. 10.2214/AJR.08.1138