³²DFP and ⁵¹Cr for Measurement of Red Cell Life Span in Abnormal Hemoglobin Syndromes

The red cell life span was measured simultaneously using ⁵¹Cr and ³²DFP in 21 patients with abnormal hemoglobin β chains and in 7 patients with normal hemoglobin. The patients included 9 with sickle cell anemia, 2 with sickle-β-thalassemia disease, 2 with sickle cell-hemoglobin C disease, 3 with homozygous hemoglobin C disease, 4 with sickle cell trait and 1 with hemoglobin C trait. The ⁵¹Cr elution rate from red cells carrying abnormal β chains was 1.2 per cent daily (range: 0.1-2.7 per cent; 4 patients had 2-component elution curves, the first of which was quite rapid (4.1-19.5 per cent daily) and could lead to significant error in the ⁵¹Cr estimate of red cell survival. The ⁵¹Cr elution rate for red cells with normal β chains was 1.3 per cent daily (range: 0.7-1.6 per cent). In the steady state, production of red cells was estimated from the ³²DFP life span. Both figures varied with the disease process but erythropoiesis seldom obtained the 6-8 fold increase over normal that is considered to be the capability of normal bone marrow and hence a relative erythropoietic defect seems to be frequently present in patients with abnormal hemoglobin diseases. Two sibling pairs with sickle cell anemia were studied and were found to vary from each other as much as did the other patients with this disorder.