New evidence of red blood cell rheological disorders in beta-thalassaemia minor.

Haemorheological parameters, such as red blood cell deformability, membrane elastic modulus and membrane surface viscosity in twenty one thalassaemia heterozygous patients (14 beta0/beta and 7 beta+/beta) were compared with normal individuals (n = 15). Parameters were measured applying a laser diffractometric method (ektacytometry). Thalassaemia erythrocytes showed statistically significant lower deformability and higher elastic modulus. Surface viscosity showed no significant differences in thalassaemia. Creep and recovery curves were registered by diffractometry. The normal recovery curve was fitted by a first order exponential decay function, expressing the fitting degree by the chi2 coefficient. The shape of the recovery curve in beta-thalassaemia patients (beta0/beta or beta+/beta) was significantly different from the control group. The possible mechanism of red blood cells abnormal rheological behaviour in beta-thalassaemia minor could be explained by a surface charge reduction. Our results enable us to conclude that the shape of the recovery curve (chi2 coefficient) could be considered as a marker that might be useful in beta-thalassaemia diagnosis.