Thank you for your recent inquiry.
Unfortunately I am not sure that I can be of any practical help to you in this regard. If one looks up a list of causes of elevated IgA, you see a total of 48 different diagnoses. They are divided into infections, neoplastic disorders, autoimmune disorders, neoplasms, congenital disorders, immune deficiencies (e.g., Wiskott-Aldrich, et cetera), poisonings (acute alcoholic hepatitis), and gastrointestinal diseases such as gluten enteropathy. However, none of these seem to fit your patient.
The most important thing that one can do is rule out monoclonality. To do this you could order an immunoelectrophoresis or an immunofixation. This would rule out any monoclonal elevation of IgA such as would occur in a malignancy.
I can only add an anecdotal comment in that it is not terribly unusual to see elevations of IgA of this magnitude without known cause.
Phil Lieberman MD