Related Experiment Video
Updated: Jun 25, 2026

An Ex Vivo Model of Ovarian Cancer Peritoneal Metastasis Using Human Omentum
Published on: January 26, 2024
IgG4-related disease presenting as an omental mass
Avyukta Krishna Nair1, Zechen Ma2, Christian Pagnoux3
1Medicine, Poznan University of Medical Sciences, Poznań, Poland.
Abstract:
A woman in her late 20s presented with severe subacute right-sided abdominal pain. Laboratory investigations revealed elevated inflammatory markers and normal serum IgG4 levels. Abdominal and pelvic CT revealed an omental lesion, with inflammatory stranding along the right paracolic gutter. Colonoscopy revealed an inflamed right colon with no specific lesions. Right colonic and omental biopsies showed inflammatory changes with a prominent plasma cell infiltrate in the omental mass, with IgG4-positive plasma cells on immunohistochemistry (IgG4:IgG ratio 40%-50%), but no storiform fibrosis or venulitis. After considering an extensive differential diagnosis, these findings were most consistent with IgG4-related disease (IgG4-RD). The patient responded to high-dose glucocorticoids but was unable to taper it below 10 mg/day. She received rituximab with complete resolution of symptoms and almost radiographic improvement.Intraperitoneal and omental tumoral manifestations of IgG4-RD are rare.
Related Concept Videos
Appendicitis
Appendicitis-I: Introduction
Etiology: Appendicitis can arise from various causes, primarily rooted in the obstruction of the appendix lumen. Factors contributing to this obstruction include fecal accumulation, lymphoid hyperplasia and, in...
Diseases of the Liver and Gallbladder
Cirrhosis is characterized by the scarring of hepatic lobules in the liver, which are replaced by fibrous tissue, affecting the liver's normal functioning. NAFLD, on the other hand, is caused by an excessive build-up of fat in the liver, not related to...
Cholecystitis
Pyloric Obstruction
Gallbladder
The gallbladder's anatomy consists of three regions: the fundus, body, and neck. Extending from the neck, the cystic duct joins the common...
