Immunohistochemical signs of IgG4-related disease in patients with inflammatory bowel diseases

Abstract

To determine immunohistochemical features of IgG4-related disease in patients with inflammatory bowel diseases (IBD). Immunohistochemical testing of colonic biopsy material from 35 patients with IBD (24 cases of ulcerative colitis and 11 cases of Crohn's disease) was carried out using IgG, IgG4 and CD138 antibodies. The number of IgG4- and CD138-positive cells was counted in high power field of microscope (×400). Patient selection was random. IgG4-positive cells were detected in the colonic mucosa of 5 patients with ulcerative colitis. The age of the patients ranged from 24 to 47 years. Two patients had a total, and three had a left-sided lesion of the colon. The anamnesis of the disease ranged from 3 to 13 years. The number of positively stained cells in the reaction with the antibody to IgG4 varied from 2 to 50 in high power field of microscope. We were able to detect over 10 IgG4-positive cells in 3 females aged 28, 30 and 31 years with a long history of ulcerative colitis (5, 4 and 3 years, respectively). Two patients had a total lesion of the colon, all three had an exacerbation of the disease, and a morphological study revealed chronic diffuse active erosive colitis. A high degree of histological activity and pronounced diffuse basal plasmacytosis were noted. In one of the cases, the infiltrate captured the muscular lamina of the mucosa and areas of the submucosa. IgG4-positive cells in the inflammatory infiltrate, including those with an excess of more than 10 in the field of view of the microscope at high magnification, can be observed in patients with ulcerative colitis with severe and prolonged course of the disease. To classify this colitis as a manifestation of an IgG4-related disease, the results of immunohistochemical studies alone are not enough. It is required to accumulate a larger number of observations, as well as to search for other diagnostic criteria for an IgG4-related disease in these patients.