MRCP revision battle 33.2: Hyperviscosity syndrome

Hyperviscosity syndrome is a condition in which the viscosity (='stickiness') of the blood has increased to a degree which prevents easy flow through the microcirculation.



This causes symptoms such as:

• lethargy
• confusion
• headache
• visual disturbances
• spontaneous bleeding

The visual disturbance is described as 'looking through a watery car windscreen'
The optic disc may occur blurred.



Normal plasma viscosity is 1.4-1.8.  Hyperviscosity syndrome develops above around 4.



Causes of hyperviscosity syndrome include:

• myeloma
• Waldenstroms macroglobulinaemia
• leukaemias
• polycythaemia

Treatment depends on the cause; in myeloma/waldenstroms the patient needs plasmaphersis whereas in polycythaemia the treatment is venesection.



So now seems a good time to battle Waldenstrom's macroglobulinaemia...