Hyperfibrinogenaemia and hyperviscosity in sickle-cell crisis.

Plasma fibrinogen concentration and whole-blood viscosity, the latter measured at two shear rates (23 and 230 sec-1), were estimated during eight episodes of sickle-cell crisis and compared with values in 26 sickle-cell anaemia patients who were not in crisis. Painful crisis was associated with a significant increase in both plasma fibrinogen and whole-blood viscosity. Increased fibrinogen-erythrocyte interaction in vivo may be a significant contributory factor to raising blood viscosity and precipitating vaso-occlusive crisis in sickle-cell disease.