To The Editor: The tendency to report isolated cases of a disease benefited by a new form of therapy often imposes an unduly optimistic bias on the outlook with such therapy for the disease in general. With further experience the true value of the therapy usually becomes clear.
Folic acid therapy in children with thalassemia major is a case in point (Amer J Dis Child 105:275-280 [March] 1963). Initially stimulated by earlier enthusiastic reports1,2 we have studied ten patients with this disease in an attempt to evaluate various indices of folic acid deficiency with a view to therapy with this drug. Five of the ten were found to have folic acid deficiency as indicated by low serum folic acid levels and the presence of formiminoglutamicaciduria following histidine loading. Three of these five patients showed megaloblastic changes in the bone marrow. All five were treated with oral folic acid in