Study on high blood viscosity, with special reference to paraproteinemia

The clinical syndrome secondary to the elevated blood viscosity, called as “serum hyperviscosity syndrome”, “blood high viscosity syndrome”, or “syndrome of hyperviscosity” has been paid attention recently. In clinical practice we frequently see hyperviscosity syndrome associated with paraproteinemia. We present hemorheological studies on eleven cases of multiple myelomas (IgG 6 and IgA 5) and two cases of macroglobulinemia. Among eleven cases multiple myelomas two patients manifested epistaxis and gingival bleeding presumably due to hyperviscosity of the blood.We measured blood viscosity by using capillary viscometer and Brookfield microviscometer at 37°C and 20°C respectively. The plasma relative viscosities of thirteen cases at 37°C ranged between 1.84 and 4.47 with the avarage 2.69 (normal 1.72±0.06). The whole blood viscosities at 37°C 115sec-1 fell between 3.25 and 6.09cp with the average 4.88cp (normal 4.2±0.3). The only 500% of cases revealed abnormal viscosity of whole blood. The plasma containing a large amount of paraprotein showed nonnewtonian behavior. The clear relation was noted between paraprotein concentration and plasma relative viscosity. The shear dependency (ηWB11.5sec-1/ηWB230sec-1) was follow: IgG<IgA