What is the diagnosis and management for a patient with worsening left upper quadrant abdominal pain after eating over the past few months?

Worsening Left Upper Quadrant Abdominal Pain After Eating

The most likely diagnosis is chronic mesenteric ischemia, and you should obtain CT angiography (CTA) immediately to evaluate for mesenteric arterial stenosis or occlusion. 1, 2

Diagnostic Approach

Initial Imaging Strategy

• CT angiography of the abdomen is the preferred initial imaging modality for evaluating postprandial left upper quadrant pain with weight loss, as it can identify mesenteric arterial stenosis or occlusion with high accuracy 1, 2

• Look specifically for atherosclerotic disease involving the celiac artery, superior mesenteric artery (SMA), and inferior mesenteric artery (IMA) origins 1

• The classic presentation of chronic mesenteric ischemia includes postprandial abdominal pain ("intestinal angina"), fear of eating, and weight loss over several months 1

• Severe ostial narrowing or occlusion of at least 2 of the 3 mesenteric arteries is the most characteristic finding, though symptoms typically don't appear until severe vascular compromise is present 1

Alternative Diagnoses to Consider

If CTA shows compression of the celiac artery by the median arcuate ligament (MAL) with patent SMA and IMA:

• Obtain mesenteric angiography in lateral projection during both inspiration and expiration to confirm MAL syndrome 1
• This diagnosis is controversial but should be considered when other causes are excluded 1

If CTA shows no vascular pathology, consider functional dyspepsia:

• Test for Helicobacter pylori and treat if positive 2
• Offer acid suppression with proton pump inhibitors (PPIs) or H2-receptor antagonists if symptoms persist 2, 3
• Functional dyspepsia is the most common cause of postprandial upper abdominal pain when structural abnormalities are excluded 2, 4, 5

Other important differential diagnoses:

• Peptic ulcer disease: pain typically occurs 2-3 hours after eating with duodenal ulcers, or immediately after eating with gastric ulcers 4, 6
• Chronic pancreatitis: pain radiates to the back 4
• Splenic pathology, gastric abnormalities, or renal disease 2

Management Based on CTA Findings

If Atherosclerotic Mesenteric Stenosis is Confirmed

Angiography with percutaneous transluminal angioplasty and stent placement is the preferred initial treatment (rated 8/9 by ACR) 1

• Endovascular therapy has 85-100% technical success rates when stents are used 1
• Prioritize treatment of the SMA and use covered balloon-expandable stents for optimal outcomes 1
• Endovascular therapy has lower perioperative complications compared to open surgery (P = .006 in propensity-matched studies) 1

Surgical bypass or endarterectomy (rated 7/9 by ACR) is reserved for:

• Patients where endovascular approach is not technically feasible 1
• Failed endovascular therapy 1
• Patients requiring concurrent abdominal surgery 1

Systemic anticoagulation alone (rated 5/9 by ACR) is generally not appropriate as primary therapy but may be complementary to revascularization 1

If Median Arcuate Ligament Syndrome is Confirmed

Surgery with median arcuate ligament release is the primary treatment (rated 8/9 by ACR) 1

• Surgical release provides symptomatic relief in 84.6% of patients 1
• Consider vascular reconstruction (primary reanastomosis or interposition grafting) in addition to decompression for better long-term outcomes—76% persistent symptom resolution versus 53% with decompression alone 1
• Complete resolution of symptoms occurs in 75% of patients at 6 months when reconstruction is performed 1

Percutaneous transluminal angioplasty with stent placement (rated 4/9 by ACR) is only appropriate as second-line intervention for recurrent or persistent symptoms despite surgical decompression 1

If No Vascular Pathology is Found

Treat for functional dyspepsia or peptic ulcer disease:

• Test for H. pylori using urea breath test, stool antigen, or endoscopic biopsy 2
• If H. pylori positive: eradicate with short-course antibiotic therapy 2
• First-line acid suppression: PPIs (e.g., omeprazole 20 mg daily) or H2-receptor antagonists (e.g., ranitidine 150 mg twice daily) 2, 3
• Second-line for refractory symptoms: tricyclic antidepressants to modulate pain perception at the gut-brain axis 2

Critical Pitfalls to Avoid

• Do not dismiss postprandial pain with weight loss as functional without obtaining CTA—chronic mesenteric ischemia can progress to acute mesenteric ischemia with bowel infarction, which has high mortality 1, 2

• Do not delay revascularization in confirmed mesenteric ischemia—the rich collateral blood supply means symptoms don't appear until severe compromise exists, and progression can be rapid 1

• Do not use opioids for chronic abdominal pain management—they worsen outcomes and should be avoided 5

• Consider endoscopy if alarm features are present: older age, family history of upper GI malignancy, weight loss, or anemia require endoscopy to exclude malignancy 2