Frequency, clinical picture, diagnosis, and differential diagnosis of the pathology of the digestive tract (esophagus, stomach, and bowel) in IgG4-related disease (autoimmune pancreatitis)

Abstract

Despite the publication of European guidelines for the diagnosis and treatment of IgG4-related disease (IgG4-RD), this problem is very complicated from a practical point of view. There are many publications about autoimmune pancreatitis and liver and biliary tract lesions in IgG4-RD, but the data on the digestive tract lesions are not sufficient. Gastrointestinal manifestations of IgG4-RD are considered to be rare or very rare.
 IgG4-RD presenting as esophageal lesions is rare condition. Only single clinical cases are available. I. Obiorah et al. reported the highest number of cases of IgG4-related esophagitis (8 cases). Interestingly, 7/8 cases reported by I. Obiorah et al. were males (age range: 18 to 79 years), and most patients had dysphagia as the most prominent symptom, with erosions and strictures at endoscopy. Histologically, all patients had a lymphoplasmacytic infiltrate and storiform fibrosis, while obliterative phlebitis was observed in 3/8 patients. Hence, 2 of the 3 major histological “Boston criteria” of IgG4-RD were fulfilled in all patients. Besides, all patients had at least 50 IgG4-positive cells per HPF (range: 50–110), and IgG4/IgG ratios of at least 50% (range: 50–90%). Of I. Obiorah’s patients, s-IgG4 had only been measured in three — all of whom had values in the normal range. Esophageal strictures were identified in three patients, two patients had achalasia.
 Based on K. Notohara’s series and the other published cases, it can be concluded that gastric IgG4-RD often (but not always) seems to be clinically asymptomatic, that s-IgG4 is elevated in a considerable number of cases, and histologically, that at least two of the Boston criteria often are found. The recommended cut-off of 50 IgG4-positive cells and IgG4/IgG ratios of >40% was often fulfilled in the reported cases of IgG4-RD.
 There are few reports of IgG4-RD involving the duodenum, duodenal papilla, ileum with small bowel obstruction caused by pseudotumor or sclerosing disease of the small bowel with luminal narrowing.
 There are case reports of IgG4-RD with lesion of ileocecal area with an obstructing ileocecal mass and appendix, mimicking Crohn’s disease, appendicitis or appendiceal tumor. IgG4-related inflammatory bowel disease may — rarely — also be one of manifestations of IgG4-RD.
 Treatment should be conducted in accordance with European guidelines.