[Heterocygous beta thalassaemia (author's transl)].

Two girls with an heterocigotic beta-thalassemy are presented in this study. Case 1 has an hypochromic and microtic anaemia with an enormous splenomegaly, increased osmotic resistence of red blood cells in salted solution and increase of A2 hemoglobin. This situation is associated with an increase of the glucolitic intraerythrocitic enzimes. Case 2 showed increase of A2 hemoglobine, but this anomaly was associated with decrease of intraerythrocitic enzimatic rate. First clinical signs of erythrocitic disturbances was an acute hemolytic crisis developed by the supply of the sulphometoxipiridacine. The erythroquinetic study showed a decrease of the average life of the red blood cells in both patients.