CD79A and agammaglobulinemia: Subsequently, some patients develop commonvariable hypogammaglobulinemia.[8,10] The use of drugs such as D–penicillamine,sulfasalazina, captopril, valproic acid, carbamazepine, ibuprofen, and exposure to certaininfections (rubella, cytomegalovirus [CMV], toxoplasmosis) can cause reversible IgA deficiency.Seasonal variations of IgA antibodies was also described, these increasing in winter.