Flexibility of erythrocytes in juvenile diabetes mellitus.

The rheological properties of erythrocytes of 47 diabetic children and adolescents were studied. Deformability of red cells of 32 patients under "poor" metabolic control was markedly decreased while the deformability of red cells of patients (15 individuals) under "good" control was normal. This diminished flexibility of erythrocytes of patients under "poor" control can be explained partly by an increased concentration of free fatty acids in plasma. Moreover we found a decreased fluidity of the intracellular hemoglobin caused possibly by a decreased concentration of 2, 3-diphosphoglycerate in the cells.