Splenic sequestration and ineffective erythropoiesis in hemoglobin E-beta-thalassemia disease.

A 13-year-old Thai female with hemoglobin E-beta-thalassemia was evaluated for anemia and splenomegaly. Globin chain synthesis in a whole cell system revealed an absence of betaA chains and excessive alpha chains. The alpha/betaE + gamma ratio was 1.26 in bone marrow and 1.90 in peripheral blood. The average gamma/betaE ratio in bone marrow and peripheral blood was 0.36 compared to peripheral blood concentrations of 49% hemoglobin E and 51% hemoglobin F. Homologous red cell 51Cr half-life increased from 22.7 days to 32.8 days after splenectomy. Total circulating hemoglobin increased from 112.9 to 149.7 g. Endogenous carbon monoxide productive (Vco) as a measure of total heme catabolism decreased from 2.00 to 1.54 mumol/hr/kg. Ineffective erythropoiesis was manifested by an increased Vco/Vheme-c ratio of 7.52.