Differential Diagnosis for Superior Mesenteric Ischemia
Single Most Likely Diagnosis
- Acute Mesenteric Thrombosis: This is often considered the most likely diagnosis due to its direct involvement with the superior mesenteric artery, leading to ischemia of the bowel. It typically occurs in the setting of atherosclerosis, cardiac emboli, or hypercoagulable states.
Other Likely Diagnoses
- Non-occlusive Mesenteric Ischemia (NOMI): This condition occurs without a fixed obstruction of the mesenteric arteries but is due to a low-flow state, often seen in critically ill patients, heart failure, or after major surgery.
- Mesenteric Venous Thrombosis: Although less common than arterial thrombosis, it can cause bowel ischemia and is often associated with hypercoagulable states, portal hypertension, or local factors such as pancreatitis.
- Embolic Occlusion of the Superior Mesenteric Artery: Typically originating from cardiac sources such as atrial fibrillation, this can suddenly occlude the superior mesenteric artery, leading to acute ischemia.
Do Not Miss Diagnoses
- Intestinal Obstruction: While not a direct cause of ischemia, obstruction can lead to ischemia if not promptly treated, especially if it involves a closed-loop obstruction or strangulation.
- Inflammatory Bowel Disease (IBD) Flare: Although not primarily a vascular issue, severe flares of IBD can lead to bowel ischemia due to inflammation and potential thrombosis.
- Vasculitis Involving the Mesenteric Arteries: Conditions like polyarteritis nodosa or systemic lupus erythematosus can cause inflammation of the mesenteric arteries, leading to ischemia.
Rare Diagnoses
- Median Arcuate Ligament Syndrome (MALS): A rare condition where the median arcuate ligament compresses the celiac trunk, potentially leading to chronic mesenteric ischemia, though it's more commonly associated with the celiac trunk than the superior mesenteric artery.
- Takayasu Arteritis: A large vessel vasculitis that can involve the mesenteric arteries, leading to ischemia, though it's rare and typically presents in younger women.
- Fibromuscular Dysplasia: A non-atherosclerotic, non-inflammatory vascular disease that affects medium- and large-sized arteries, including potentially the mesenteric arteries, leading to stenosis or aneurysm formation.