Clinical course of patients with major histocompatibility complex class IIdeficiency

The clinical course of 10 children who have been diagnosed with major histo compatibility complex (MHC) class II deficiency (bare lymphocyte syndrome) in the UK over the past eight years is described. They have had a generally poor prognosis, with only two of the 10 still alive despite eight attempts at bone marrow transplantation in six patients. Overwhelming viral infecti on was the predominant cause of death. Alternative transplant strategies or novel therapies are required for these patients.