[X-linked Bruton congenital agammaglobulinemia. Case report].

Congenital agamaglobulinemia is a B-cell deficiency caused by tirosin-kinase gene mutations. This article presents the case of a 2 years and 6 months old boy with a history of multiple respiratory infections, which also associates a malabsorbtion syndrome. The patient presented for symptoms of arthritis. After performing protein electrophoresis, the extremely low gamma fraction pointed out a hidden immunodeficiency. Gene analysis was performed in the Department of Pediatric Immunology of Debrecen University, Hungary and thus the final diagnosis was determined. Arthritis and respiratory symptoms improved after immunoglobulin treatment.