[Pathologic fluidity, glycohemoglobin and erythrocyte metabolism disorder in Fontaine II diabetic macroangiopathy]

This pilot study set out to evaluate the influence of metabolic disorders due to diabetes mellitus on red blood cell (RBC) substrates, deformability and glycohaemoglobin (HbA1) levels. RBC deformability was measured optoelectronically by microcomputer-assisted polymicroviscometry (filtrometry) following separation of RBC into old (dense) and young (buoyant) fractions by means of density-layer centrifugation. 20 adult patients with type II diabetes mellitus associated with Fontaine II macroangiopathy underwent RBC investigations before and after diabetic therapy. Those RBC fractions containing older cells exhibited impaired metabolism, increased HbA1 levels and markedly altered deformability which significantly differed from values obtained from young RBC fractions. However, old RBC fractions only of patients treated for diabetes persistently displayed a slight increase in HbA1 levels associated with a still altered deformability, in contrast to the young RBC fractions which showed normal values again after diabetic treatment. The preliminary results suggest an adaptive alteration of RBC metabolism and function in diabetes, predominantly existing in old RBC, which still persists only in old RBC fractions after diabetic therapy. Thus, a prolonged pathologic effect of older RBC on the peripheral microcirculation may occur in diabetes, resulting in a further persistent maintenance of diabetic vascular disease.