An **Anti-Saccharomyces cerevisiae Antibodies (ASCA IgG)** test is a blood test used to help diagnose inflammatory bowel disease (IBD) and distinguish between its two main types: **Crohn’s disease** and **Ulcerative Colitis**.
The test detects IgG antibodies that target *Saccharomyces cerevisiae*, a common type of dietary yeast.
Elevated levels of ASCA IgG are strongly associated with Crohn’s disease, particularly cases involving the small intestine. When combined with other autoantibody markers, a positive ASCA IgG result provides crucial diagnostic clarity, helping clinicians assess the severity of disease progression and tailor effective treatment strategies.