Anergy, zinc deficiency, and decreased nucleoside phosphorylase activity in patients with sickle cell anemia.

Cell-mediated immunity was evaluated in 26 patients with sickle cell anemia using skin tests for delayed hypersensitivity reactions. Patients with impaired delayed hypersensitivity reactions had lower zinc levels in plasma, erythrocytes, and neutrophils than patients with normal delayed hypersensitivity reactions or controls. The activity of nucleoside phosphorylase, an enzyme essential for T-lymphocyte function, was significantly lower in zinc-deficient patients with anergic sickle cell anemia. We conclude that zinc deficiency in patients with sickle cell anemia is associated with impaired delayed hypersensitivity. Decreased activity of nucleoside phosphorylase may be partially responsible for lymphocyte dysfunction in these patients.