IBD Expanded Panel (Inflammatory Bowel Disease)
A panel of serological markers that helps distinguish Crohn's disease from ulcerative colitis and flags Crohn's disease at higher risk of an aggressive course.
Inflammatory bowel disease (IBD) is a chronic disorder of the lower gastrointestinal tract. It takes three main forms — Crohn's disease (CD), ulcerative colitis (UC), and indeterminate colitis (IC) — and affects roughly 0.3% of adults. Telling one form from another is often difficult and time-consuming, and the diagnostic gold standard, endoscopy with biopsy, is invasive. Blood-based serological markers offer a less invasive way to support the differential diagnosis and to signal disease likely to behave aggressively.
The two long-established markers are anti-Saccharomyces cerevisiae antibodies (ASCA) and atypical perinuclear anti-neutrophil cytoplasmic antibodies (pANCA). ASCA are directed against a carbohydrate in the cell wall of baker's/brewer's yeast — a dietary and gut antigen rather than the body's own tissue — and are seen predominantly in Crohn's disease. pANCA is seen predominantly in ulcerative colitis. In combination, an ASCA-positive / pANCA-negative pattern can reach a specificity as high as ~99% for separating CD from UC, though a meaningful share of IBD patients are negative for both.
To improve sensitivity, this expanded profile pairs pANCA with four Crohn's-associated antibodies: gASCA (a glycan-based anti-yeast IgG), antilaminaribioside (ALCA, IgG), antichitobioside (ACCA, IgA), and antimannobioside (AMCA, IgG). Beyond diagnosis, these carry prognostic weight: in Crohn's disease, the more of these markers that are positive — and the higher their levels — the greater the association with small-bowel involvement and a complicated, aggressive disease course (strictures, fistulae, or need for surgery).
How results are interpreted:
| Result pattern | Suggested interpretation |
|---|---|
| Only pANCA positive | Ulcerative colitis |
| One of gASCA/ACCA/ALCA/AMCA positive, pANCA negative | Crohn's disease (risk not stratifiable) |
| One of gASCA/ACCA/ALCA/AMCA positive, pANCA positive | Inflammatory bowel disease, form not specified |
| Any two of the four positive (pANCA + or −) | Crohn's disease, high risk of aggressive behavior |
| Three or more of the four positive (pANCA + or −) | Crohn's disease, very high risk of aggressive behavior |
| All markers negative | Not suggestive of IBD |
Results should always be interpreted alongside clinical findings and other tests; a negative panel lowers the likelihood of aggressive disease but does not rule out future complications.
Show more
Biomarkers included in this panel:
The IBD Expanded Panel test offers three novel markers: - antichitobioside IgA (ACCA), - antilaminaribioside IgG (ALCA), - antimannobioside IgG (AMCA), together with anti-Saccharomyces cerevisiae IgG (gASCA) and pANCA.
Learn moreThe IBD Expanded Panel test offers three novel markers: - antichitobioside IgA (ACCA), - antilaminaribioside IgG (ALCA), - antimannobioside IgG (AMCA), together with anti-Saccharomyces cerevisiae IgG (gASCA) and pANCA.
Learn moreThe IBD Expanded Panel test offers three novel markers: - antichitobioside IgA (ACCA), - antilaminaribioside IgG (ALCA), - antimannobioside IgG (AMCA), together with anti-Saccharomyces cerevisiae IgG (gASCA) and pANCA.
Learn moreAntigliadin IgG (native) is an antibody test that detects immune system reactivity to gliadin, a key protein found in gluten (wheat, barley, and rye). This test measures IgG antibodies, which are associated with delayed immune responses rather than t
Learn moreASCA IgA
Anti-Saccharomyces cerevisiae antibody (ASCA) IgA is an immune protein directed against a sugar in the cell wall of common yeast — not against your own tissue. It shows up far more often in people with Crohn's disease than in ulcerative col
Learn moreASCA IgG
Anti-Saccharomyces cerevisiae antibody (ASCA) IgG is an immune protein directed against a sugar in the cell wall of common yeast — not against your own tissue. It appears far more often in people with Crohn's disease than in ulcerative coli
Learn moreAtypical perinuclear antineutrophil cytoplasmic antibodies (p-ANCA) occur in most patients with ulcerative colitis but only in a minority of those with Crohn's disease.
Learn moreThis marker is usually part of a test called IBD Expanded Panel (IBD = Inflammatory Bowel Disease) and aids in the diagnosis of inflammatory bowel disease and the differential diagnosis of Crohn’s disease (CD) and ulcerative colitis (UC);
Learn moreAnti-Saccharomyces cerevisiae antibodies (ASCA) are immune proteins found in people with inflammatory bowel disease (IBD), which is a chronic condition characterized by swollen and damaged tissues in the intestinal tract. The ASCA test detects these
Learn moreSaccharomyces cerevisiae, IgG measures antibodies your immune system has made against baker's and brewer's yeast — a dietary and gut antigen, not your own tissue. It is reported in Units across three tiers rather than as a simple high o
Learn more