A case of IgG4-related disease complicated by duodenal bulbitis with IgG4-positive plasma cell infiltration

Review of IgG4-related disease

IgG4-related disease is a fibrous-inflammatory process related to immunomodulation. The most commonly affected organs are: the pancreas, bile duct, major salivary glands, lacrimal glands, retroperitoneum and lymphatic ducts. In recent decades, this disease has been recognised as a systemic disorder that includes many single organ disorders, previously unrelated and known as independent entities. The common characteristics shared by the different entities that make up the IgG4-related disease are: raised serum IgG4 levels, alterations in the imaging tests with neoplastic-like swelling of the affected organs, specific histopathological characteristics and in immunostaining, as well as good response to treatment with glucocorticoids. In this work, we will review this pathology with a special emphasis on the characteristics of autoimmune pancreatitis, sclerosing cholangitis related to IgG4 and the involvement of the retroperitoneum, mesenterium and the digestive tract.

Multivisceral IgG4-related disease presenting as recurrent massive gastrointestinal bleeding: a case report and literature review

Background

IgG4-related disease (IgG4-RD) is a newly recognized autoimmune systemic disorder characterized by elevated levels of serum IgG4 and abundant infiltration of IgG4-positive plasmacytes in the affected organs. The liver, biliary system and pancreas are the most commonly affected organs. However, involvement of the digestive tract is very rare. To date, only a few cases of isolated gastric IgG4-RD have been reported.

Case presentation

We present a case of IgG4-RD of the liver, gallbladder, pancreas and duodenum, which was clinically misinterpreted and thereafter over-treated. A 52-year-old male presented with obstructive jaundice for 3 years, melena for 5 months and hematemesis for 10 days. Three years prior, the patient had undergone biopsies of pancreatic lesions, liver lesions, cholecystectomy and choledochojejunostomy. Histopathology showed chronic inflammatory changes. Endoscopy at admission revealed a duodenal ulcer with active bleeding. Despite medical management, the patient presented with repeated gastrointestinal bleeding. Upon evaluation, serum IgG4 levels were found to be elevated. Histopathology of the duodenal ulcer biopsy and repeated examination of the gallbladder and pancreatic and liver biopsies confirmed IgG4 positive plasma cell infiltration. A definitive diagnosis of IgG4-RD was made and steroid administration was initiated. At last follow up, 11 months to-the-day after initiating steroid treatment, the patient was asymptomatic.

Conclusions

Notably, IgG4-RD of multiple digestive organs is still very rare. As a systemic disease, it is characterized by the infiltration of IgG4-bearing plasma cells and raised IgG4 levels. Histopathology findings remain the diagnostic gold standard for this disorder.