Presentation
Right lower quadrant abdominal pain, nausea
Patient Data
Noncompressible, thickened, hyperemic appendix measuring 12 mm at widest point. Hyperechoic periappendiceal fat.
Incidental oval structure in lower abdomen near midline.
Appendix is thickened, measuring 11 mm at its widest point, and does not fill with air or contrast material. Mild periappendiceal fat infiltration, minimal amount of free fluid in pelvis.
Lentiform lesion measuring 4.4 x 3.1 x 4.3 cm in lower abdomen, with thin, regular, well-defined walls. Lesion is hyperdense (approx. 125 HU) interspersed with very hyperdense streaks - contrast material? Calcification? It is unclear whether lesion is located entirely outside ileum or is intramural/shares common wall.
Differential diagnosis includes leiomyoma and Meckel diverticulum.
Case Discussion
A young male presented to the ED with clinical signs of acute appendicitis. Complete blood count: mild leukocytosis.
Signs of appendicitis and incidental benign appearing lesion at US and CT. Resection of the lesion at appendectomy was recommended as a preventive measure, so that the lesion would not serve as a lead point for intussusception or cause ileal volvulus.
At surgery, an inflamed appendix was resected. The oval lesion was located 40 cm proximal to the ileocecal valve. The lesion was removed, along with 8 cm of ileum.
Pathology report for appendix: "Acute appendicitis."
Pathology report for lesion:
"Sections show cystic subserosal nodule containing organic material of unclear origin surrounded by histiocytes, fibrous capsule and duplicated muscular wall. May be compatible with cystic intestinal duplication."
NB: Given that the lesion proved to be an intestinal duplication cyst, the intralesional high density could very well have been contrast material. This implies a connection between the ileal lumen and the intralesional space, which is rare in foregut duplication cysts.