So far I found this-
IgA

Immunoglobulin A

Est. Normal Range:
80 - 350 mg/dl

Lab-specific
Varies by age
[Immunoglobulin A (IgA) is a type of antibody that protects against infections of the mucous membranes lining the mouth, airways, and digestive tract.] http://www.lymphomation.org/tests-immunoglobulins.htm
looks like thesite/page is dated 2004 though...

when i search for cerevisiae - it mainly comes up with yeast info - Saccharomyces cerevisiae- so not sure if that related to your testing results or not.