Acute epiploic appendagitis: CT diagnosis of a rare cause of acute abdomen

Background
Acute epiploic appendagitis (AEA) is a rare, benign, and self-limiting inflammatory condition affecting the epiploic appendages, small fat-filled peritoneal outpouchings along the taeniae coli. It usually arises from torsion or spontaneous venous thrombosis of an appendage, causing localized ischemia and inflammation. Clinically, AEA manifests as sudden-onset, well-localized abdominal pain, most commonly in the lower quadrants. Its nonspecific presentation often leads to misdiagnosis as diverticulitis, appendicitis, or gynecologic disorders. Laboratory findings are typically normal or show minimal inflammatory changes, and physical examination reveals localized tenderness without systemic signs of infection. Accurate recognition is crucial, as AEA is self-limiting and responds well to conservative management with nonsteroidal anti-inflammatory drugs, avoiding unnecessary antibiotics, hospitalization, or surgical intervention. Contrast-enhanced computed tomography (CT) is the imaging modality of choice due to its characteristic and highly specific findings.
Methodology
A 32-year-old woman presented with acute, severe left lower quadrant abdominal pain lasting 24 hours, without fever, nausea, vomiting, bowel habit alterations, urinary complaints, or gynecologic symptoms. Vital signs were stable. Physical examination revealed focal tenderness in the left iliac fossa without guarding or rebound tenderness. Laboratory tests, including white blood cell count, C-reactive protein, and renal and hepatic function, were within normal limits. Initial transabdominal ultrasonography showed normal ovaries and adnexa, no free fluid, and no bowel wall thickening or diverticular disease. Due to persistent pain and inconclusive ultrasonography, a contrast-enhanced abdominal CT scan was performed.
Results
CT imaging demonstrated a well-circumscribed, ovoid lesion measuring 3.2 × 2.5 cm with fat attenuation values of −60 to −90 HU, adjacent to the antimesenteric border of the sigmoid colon. The lesion was surrounded by a thin hyperattenuating rim and mild pericolonic fat stranding. A central hyperdense focus consistent with a thrombosed vessel (“central dot sign”) was observed. No signs of diverticulitis, appendicitis, abscess, bowel wall thickening, free air, or fluid were present. These findings confirmed the diagnosis of primary acute epiploic appendagitis.
Conclusion
This case highlights the pivotal role of contrast-enhanced CT in diagnosing AEA in patients with acute, localized abdominal pain and nonspecific clinical findings. Recognition of typical imaging features allows differentiation from surgical emergencies, supports conservative management, and ensures excellent clinical outcomes while preventing unnecessary interventions.