Hi, my son has Hashimoto, Crohn s, Asthma , and CVID. We have switched doctors to an immunologist and she tested IgG, IgA, and IgM. His IgA and IgM are significantly low for his age, but IgG showed normal. What does this mean? The new doctor believes he does not have CVID, but may develop it. Note - his levels have been low for years since before any immunosuppresant drugs .