What does saccharomyces cerevisiae ab (asca) (IgG) but normal saccharomyces cerevisiae ab (asca) (IgA) mean?

Question

WHAT DOES HIGH SACCHAROMYCES CEREVISIAE AB (ASCA) (IGG) BUT NORMAL SACCHAROMYCES CEREVISIAE AB (ASCA) (IGA) MEAN?

My gastroenterologist had me do this test last year with HIGH SACCHAROMYCES CEREVISIAE AB (ASCA) (IGG) BUT NORMAL SACCHAROMYCES CEREVISIAE AB (ASCA) (IGA).  They had me re-do the test again and the same results were received.

Answer 1

Antibodies to Saccharomyces cerevisiae are found in approximately 75% of patients with Crohn's disease, 15% of patients with ulcerative colitis, and 5% of the healthy population. High antibody titers increase the likelihood of disease, especially Crohn's disease, and are associated with more aggressive disease. As the inflammation in Crohn's disease is focused at the gut mucosa, most patients have IgA antibodies to S cerevisiae and half of these also have IgG antibodies.

So a positive IgA with a negative IgG often means that you have positive saccharomyces cerevisiae. If Saccharomyces cerevisiae antibody is positive and pANCA is negative, then it is likely that the person has Crohn’s disease. If Saccharomyces cerevisiae antibody is negative and pANCA is positive, then it is likely that the person has ulcerative colitis.

Answer 2

Do you have ulcerative colitis or Crohn's disease? And what is the titer of your ASCA IgG?

Saccharomyces cerevisiae antibody test is often done in conjunction with the Perinuclear Anti-Neutrophil Cytoplasmic Antibody (p-ANCA) to distinguish whether you have Crohn's disease or ulcerative colitis.

So if you have neither Crohn's disease nor ulcerative colitis, then you can just leave this result alone.