Introduction: Primary epiploic appendagitis (PEA) is characterized by the association of localized abdominal pain with guarding. Depending on its localization, it may simulate acute appendicitis or diverticular sigmoiditis. Symptoms correspond to necrosis of the epiploic appendix due the torsion and vascular occlusion of the main epiploic pedicle.
Observation: A 34-year-old man (BMI=29.38) was examined for persistent localized abdominal pain of the left lower quadrant three days after receiving systemic antibiotic therapy for what was diagnosed as mild diverticular sigmoiditis. Abdominal examination showed localized guarding in the left lower quadrant, with no fever, vomiting or diarrhea. Laboratory results showed no inflammatory response. Abdominal ultrasound showed no evidence of left hydronephrosis. Helical CT showed a localized zone of necrosis of the epiploic appendix of the sigmoid colon and thus confirmed the diagnosis without surgical exploration. Symptoms regressed after a week of analgesic treatment.
Discussion: PEA is a rare disease. It often occurs in mildly overweight adult men (around 35 years of age). The combination of acute abdomen with localized abdominal guarding and no evidence of fever or inflammation is the typical presentation. Surgical exploration (laparoscopy) can be avoided for diagnosis if helical CT shows a localized fatty zone situated outside the colon wall with a high attenuating dot point that corresponds to central necrosis of the epiploic appendix.