Reduced erythrocytic deformability in megaloblastic anemia.

Ten patients with megaloblastic anemia had erythrocytes with reduced deformability. The mean half-life for erythrocyte filtration was 9.89 minutes in these patients, compared with 5,20 minutes in controls. The half-life was inversely related to the hemoglobin concentration. After adequate vitamin replacement therapy filtrability improved significantly. Two patients had thromboembolic disease, It is proposed that the reduced erythrocytic deformability reflects membrane rigidity that might ultimately lead to hemolysis.