Sickle-cell disease and vascular occlusion – Rheological aspects

Abstract

Rheological methods have much to contribute to better understanding of the microvascular changes that characterise the asymptomatic steady state and the painful vaso-occlusive crisis of sickle-cell anaemia. Loss of deformability of the reversibly sickled cell, rather than an increase in the number of irreversibly sickled cells or in plasma viscosity, is probably the important rheological change at the onset of vaso-occlusive crisis and can be measured using positive-pressure or initial-flow-rate filtration methods. These bulk filtration methods can also be used for in vitro screening of new anti-sickling compounds and to provide an objective end point, during clinical trials of these compounds, of the resolution of crisis.