[Blood hyperviscosity syndromes].

Hyperviscosity syndromes are characterized by altered blood flow properties; the rheological properties of blood depend from cellular or plasmatic factors. In this study we have evaluated the role of some high molecular weight proteins (IgG, IgA, IgM, fibrinogen) and of some triglyceride-rich lipoprotein fractions. In Waldenström's disease a significant increase of apparent blood viscosity and plasma viscosity was observed; erythrocyte filterability was reduced. In patients with IgG and IgA myeloma just a slight increase of viscosity was observed. As for lipoprotein role, patients with hypertriglyceridemia type IV and V of Fredrickson have shown a significant increase of plasma viscosity; in these hyperlipidemias triglyceride levels were significantly correlated with both apparent blood viscosity and plasma viscosity. No correlation was observed with erythrocyte filterability. These data suggest that serum proteins and high levels of triglycerides can modify blood rheological properties with both increased viscosity and reduced erythrocyte filterability.