T-lymphocyte subpopulation abnormalities in apparently healthy patients with hemophilia.

T-lymphocyte populations in 12 apparently healthy heterosexual adult patients with hemophilia have been examined to ascertain if these patients have abnormalities in their lymphocyte subpopulations similar to those in homosexual men, Haitian refugees, and narcotic addicts. A striking reduction in the helper to suppressor cell ratio ([0.86 +/- 0.14]:1) was found in 9 of the 12 patients. These abnormalities were similar to those previously described in two patients with hemophilia critically ill with Pneumocystis carinii pneumonia, and in homosexual men. The abnormality in the ratio of helper to suppressor T cells may be related to the continual exposure of patients with hemophilia to commercial clotting factor concentrates. However, these patients with abnormal T-lymphocyte subpopulations remain healthy. At present there is insufficient evidence to advocate a change in therapeutic practices in patients with hemophilia.