X-linked agammaglobulinemia presenting as juvenile chronic arthritis: report of one case.

Bruton agammaglobulinemia (X-linked agammaglobulinemia, XLA), transmitted by X-linked recessive inheritance, affects only males. Twenty percent of patients with XLA may have arthritis. Septic arthritis may occur, but there is also a form of arthritis that is similar to rheumatoid arthritis or juvenile chronic arthritis. Here we report one case of XLA in a boy with non-erosive chronic right knee arthritis. There was no evidence of septic arthritis. Regular intravenous gammaglobulin replacement therapy and oral naproxen resulted in dramatic improvement in the arthritis. This case illustrates that XLA should be considered as a possible underlying cause of juvenile chronic arthritis in males.