Lymphocyte subsets in children with aplastic anemia

Twenty-four patients with aplastic anemia (AA) were evaluated with immunologic studies. Patients with posthepatitis AA had decreased proportions of T4 cells, increased proportions of T8 cells, and decreased T4:T8 ratios. Patients with constitutional AA had varied immunologic findings. There were no significant abnormalities in lymphocyte subsets in patients with idiopathic AA. Of the 12 patients who were treated with antithymocyte globulin (ATG), six (50%) responded. Nine of these patients are living 3-27 months after treatment; three of the nine are transfusion dependent. T-cell subsets were not helpful in predicting the response to ATG. Measurements of other immunologic mediators may be more useful with regard to pathophysiology and prognosis in AA.