Immunologic abnormalities in patients with hemophilia A.

To assess the immunologic status of healthy persons with hemophilia A, we performed studies of T cell immunity in 21 patients, 10 given only cryoprecipitate and 11 given factor VIII concentrate. Patients in the factor VIII group had significantly decreased helper/suppressor T cell ratios. Both groups had diminished mononuclear cell response to phytohemagglutinin and normal mixed lymphocyte culture, compared with controls. Abnormalities in T cell number or function did not correlate with the presence of antibody to cytomegalovirus, Epstein-Barr virus, or hepatitis B. Physicians caring for patients with hemophilia A should realize that asymptomatic individuals may have early evidence of immunodeficiency.