Hyperviscosity Syndrome: an Update for Intensivists

Abstract

Hyperviscosity syndrome (HS) is a clinical entity. It consists of various aspecific symptoms and its diagnosis relies on a set of contextual, anamnestic and clinico-biological arguments. Besides the measure of plasmatic viscosity, the most specific diagnostic tool seems to be the fundus examination. The incidence of HS is unknown as it is a rare complication of a wide range of diseases. The pathophysiology of the syndrome may be either related to an increase in plasma viscosity or to an elevation of the number of blood cells and/or an alteration of their capacity to pass through the capillaries. HS always requires a symptomatic treatment in order to decrease blood viscosity. In severe cases, urgent therapeutical apheresis may be necessary. The prognosis of HS depends on the underlying etiology.