Case report of IgG4-related appendiceal disease: A challengi
A previously healthy 42-year-old woman was admitted in the emergency department with a 1-week history of right lower quadrant abdominal pain. Physical examination revealed a painful mass in the right lower quadrant with no rebound or guarding, normal bowel sounds, and no hepatosplenomegaly. Physical examination was otherwise normal, and the initial laboratory tests were normal.

Abdominal CT scan showed a marked enlargement, thickening, and mucosal hyperenhancement of the appendix. There was no significant appendiceal distention, appendicolith, periappendicular fat stranding, or free intraperitoneal fluid. No additional abnormalities were detected on CT, including lymph node enlargement.

The patient underwent an open right hemicolectomy. On histopathological evaluation, the appendiceal wall was thickened and the mucosa was unremarkable with no evidence of acute appendicitis. There was a patchy dense transmural lymphoplasmacytic inflammatory process involving the submucosa, the muscular layer, the subserosa, and the periappendiceal tissue intermixed with spindle cell proliferation.

After the surgery, the patient had an uneventful recovery and reported a resolution of her symptoms. The serum IgG4 was revaluated 5 days after surgery and returned to its normal values. At the 3-year follow-up, the patient had no recurrence of symptoms and her imaging exams remain unremarkable.