Diagnosis
Serum viscosity can be measured. Normal is between 1.4 and 1.8 centipoises but to have symptoms from hyperviscosity, serum viscosity is usually greater than 5 centipoises. Patients will also have evidence of their underlying disorder. Those with myeloma will typically display a rouleaux formation on a peripheral smear and a large globulin gap, indicative of a significant paraprotein load. While viscosity can be directly measured, results can take a few days to return and thus a high index of suspicion is required to make the diagnosis in a timely manner. If hyperviscosity is suspected, treatment may need to be started prior to obtaining the official viscosity level.
Read more about this topic: Hyperviscosity Syndrome