What is the diagnosis and treatment of epiploic (inflammation of epiploic appendages) appendagitis?

Diagnosis and Treatment of Epiploic Appendagitis

Epiploic appendagitis is a benign, self-limiting condition that should be diagnosed with CT imaging and managed conservatively with NSAIDs and analgesics—surgery is unnecessary and should be avoided. 1, 2

What is Epiploic Appendagitis?

Epiploic appendages are peritoneal fat-filled structures arising from the outer serosal surface of the colon, containing a vascular stalk. 1 Epiploic appendagitis occurs when these appendages undergo torsion or spontaneous venous thrombosis, leading to ischemic infarction and inflammation. 3, 4

Clinical Presentation

The condition mimics acute diverticulitis or acute appendicitis, which is why it is frequently misdiagnosed. 1, 5

Key clinical features include:

• Focal, localized abdominal pain (most commonly left lower quadrant, but can occur anywhere along the colon including right lower quadrant) 1, 2
• Normal or minimally elevated white blood cell count (unlike appendicitis or diverticulitis) 3
• Absence of fever, nausea, or vomiting in most cases 2
• Pain that is often sharp and well-localized 1

Common pitfall: The clinical presentation is so similar to appendicitis or diverticulitis that the estimated rate of correct preoperative diagnosis is only 2.5%, leading to unnecessary hospitalizations, antibiotics, and surgeries. 3

Diagnostic Approach

CT imaging is the gold standard for diagnosis and should be obtained when epiploic appendagitis is suspected. 1, 5, 3

Classic CT Findings (Diagnostic Triad):

1. Fat-density ovoid lesion along the anterior colonic wall surface with hyperattenuating ring sign 1, 3
2. Central high-attenuation focus within the fatty lesion (central dot sign) representing the thrombosed vessel 1
3. Mild bowel wall thickening with surrounding rim of fat stranding 1, 3

The CT findings are pathognomonic and allow confident diagnosis without need for further invasive testing. 5, 3

Special Consideration:

When epiploic appendagitis involves the vermiform appendix region (rare), it can be particularly challenging to differentiate from acute appendicitis. 4 However, the CT characteristics remain distinct: look for the oval fatty lesion with central dot sign rather than an inflamed, dilated appendix. 4

Treatment

Conservative management is the only treatment needed—no antibiotics, no surgery, no hospitalization in most cases. 2, 3

Recommended Treatment Protocol:

• NSAIDs (non-steroidal anti-inflammatory drugs) as first-line therapy for pain control 2, 3
• Analgesics as needed for symptom management 2
• Outpatient management is appropriate for most patients 1
• Symptoms typically resolve within a few days (usually 3-7 days) 1, 2

What NOT to Do:

• Do not prescribe antibiotics—this is not an infectious process 3
• Do not perform surgery—the condition is self-limiting 1, 5, 2
• Do not hospitalize unless pain is severe and requires inpatient pain management 1

Clinical Algorithm

When a patient presents with focal abdominal pain:

1. Obtain CT scan if clinical suspicion for acute abdomen (especially if mimicking appendicitis or diverticulitis) 6, 1
2. Look for the diagnostic triad on CT: oval fatty lesion, central dot sign, fat stranding 1, 3
3. If epiploic appendagitis is confirmed: Prescribe NSAIDs, reassure patient, arrange outpatient follow-up 2, 3
4. Avoid unnecessary interventions: No antibiotics, no surgery, no prolonged hospitalization 1, 5

Key Pitfalls to Avoid

The most critical error is misdiagnosing epiploic appendagitis as appendicitis or diverticulitis and proceeding to unnecessary surgery. 1, 5 This occurs because:

• Clinical presentation is nearly identical to these conditions 1, 2
• Many clinicians are unfamiliar with this entity 3
• The diagnosis is rarely made preoperatively without CT imaging 3

Always obtain CT imaging before surgical intervention in patients with atypical presentations of abdominal pain, especially when laboratory findings (normal WBC) don't match the clinical picture. 2, 3