Serologic Markers in Inflammatory Bowel Disease

Abstract

Inflammatory bowel disease (IBD) is an enduring disease involving mostly young people, with symptoms of bloody diarrhea and abdominal cramps. Several antibodies have been associated with IBD, the 2 most comprehensively studied being autoantibodies to neutrophils (atypical perinuclear anti-neutrophil cytoplasmic antibodies) and anti-Saccharomyces cerevisiae antibodies. This review focuses on the value of these antibodies for diagnosing IBD, differentiating Crohn disease from ulcerative colitis, indeterminate colitis, monitoring disease, defining clinical phenotypes, predicting response to therapy, and as subclinical markers. Pancreatic antibodies and newly identified anti-microbial antibodies (anti-outer membrane porin C, anti-I2, and anti-flagellin) are also reviewed.

The impact of intestinal resection on serum levels of anti‐Saccharomyces cerevisiae antibodies (ASCA) in patients with Crohn’s disease

“…6 In CD, anti-Saccharomyces cerevisiae antibodies (ASCA) of the isotypes IgG or IgA have been demonstrated in sera of 60-70% of patients, particularly in those with ileal involvement. 7 Anti-Saccharomyces cerevisiae antibodies have been associated with complicated disease course, increased hospital costs and an increased risk of small bowel surgery in CD. [8][9][10][11][12][13] Saccharomyces cerevisiae is an ascomycetous yeast extensively used in the brewing and baking industry.…”

“…However, increased levels of ASCA are only found in up to 5% of the healthy population, indicating a general mucosal tolerance to the widespread yeast and its antigens. 7 As among the existing serologic markers in CD, ASCAs are most prevalent and of greatest predictive value for complicated disease course, 7 we were interested in their longterm stability. We investigated the influence of intestinal resection on ASCA serum levels of both IgG and IgA isotypes by performing serial pre-and repetitive postoperative measurements and subsequently by long-term follow-up evaluated ASCA as prognostic variable to predict the risk of surgical recurrence.…”

Revised 2017 international consensus on testing of ANCAs in granulomatosis with polyangiitis and microscopic polyangiitis

“…In addition to vasculitis, ANCAs are found in patients with gastrointestinal disorders such as IBD 88 , primary sclerosing cholangitis 89 and inflammatory liver diseases (such as autoimmune hepatitis, primary biliary cirrhosis and chronic viral hepatitis) 90 . These diseases are associated with a slightly aberrant P-ANCA pattern that is often referred to as atypical P-ANCA or X-ANCA 88 .…”

“…In gastrointestinal disorders, P-ANCA is mainly observed in patients with ulcerative colitis (50-67%), but is also seen in patients with Crohn's disease (6-15%), and to a lesser extent in disease controls (<11%) 88 . Combining P-ANCA with anti-Saccharomyces cerevisiae antibody (ASCA) measurements might improve the clinical utility of this marker.…”

“…Combining P-ANCA with anti-Saccharomyces cerevisiae antibody (ASCA) measurements might improve the clinical utility of this marker. ASCAs are found in 40-60% of patients with Crohn's disease, 4-14% of patients with ulcerative colitis and <5% of controls 88 . The combination of an ASCA-positive and P-ANCA-negative test result is associated with Crohn's disease, whereas the combination of an ASCA-negative and P-ANCA-positive test result is associated with ulcerative colitis.…”