Syndrome d’hyperviscosité plasmatique

Abstract

Hyperviscosity syndrome is a life-threatening complication. Clinical manifestations include neurological impairment, visual disturbance and bleeding. Measurement of plasma or serum viscosity by a viscometer assesses the diagnosis. Funduscopic examination is a key exam because abnormalities are well-correlated with abnormal plasma viscosity. Etiologies are various but symptomatic hyperviscosity is more common in Waldenström's macroglobulinemia and multiple myeloma. Prompt treatment is needed: treatment of the underlying disease should be considered, but generally not sufficient. Symptomatic measures aim to not exacerbate blood viscosity while urgent plasmapheresis effectively reduces the paraprotein concentration and relieves symptoms.

A clinical picture of pulmonary embolism revealing light‐chain myeloma

“…During multiple myeloma, hyperviscosity is rarer, observed in 2–6% of cases, more frequently in the forms associated with IgA. The cases associated with IgE and light chains remain exceptional . The thromboembolic risk is often due to the increased production of factor VIII, Willebrand factor, and pro‐inflammatory cytokines including CRP, interleukin 6, and interferon α .…”

Physiological role of plasma and its components and the clinical implications of different methods of apheresis: A narrative review

“…The determinants of blood viscosity are hematocrit, red blood cell deformability, other blood cells, plasma viscosity, and temperature. [22][23][24][25] Apart from viscosity, the blood's resistance to flow depends on vessel length and radius and is expressed in centipoises (cp) which are equivalent to 1 millipascal second. 26,27 To estimate this resistance: Equation Hagen-Poiseuille R = 8ηL/πr4; R = resistance of the substance to flow; L = vessel length; η = blood viscosity; r = vessel radius.…”

“…26,28,29 Blood hyperviscosity syndromes can be classified as cellular hyperviscosity or plasma hyperviscosity. 25 Increased plasma viscosity is observed with increased plasma proteins, which increase the plasma's internal resistance to moving forward. Compared to large linear and asymmetric proteins (fibrinogen or IgM, IgA), smaller spherical proteins have minor role in increasing viscosity.…”

Prognosis of hyperviscosity syndrome in newly diagnosed multiple myeloma in modern-era therapy: A real-life study

“…HVS results from a high blood viscosity due to an abnormal protein or cellular element increase, frequently secondary to plasma cell disorders with immunoglobulin (Ig) ( 4 ). The clinical triad of HVS includes mucosal bleeding (epistaxis, gum), visual abnormalities (blurring, papilledema, retinal bleeding, venule thrombosis), and neurological abnormalities (drowsiness, ataxia, cerebral bleeding) ( 4 ). In a context of HVS suspicion or for asymptomatic patients with a high protein concentration, the diagnosis can be confirmed by ophthalmologic examination.…”