Test Code SVISC Viscosity, Serum
Specimen Required
Collection Container/Tube: Red top (serum gel/SST are not acceptable)
Submission Container/Tube: Plastic vial
Specimen Volume: 3 mL
Collection Instructions:
1. Keep specimen at 37° C (eg, 37° C Thermopak, heat block) until after centrifugation.
2. Centrifuge and aliquot serum into plastic vial.
Useful For
Detection of increased viscosity
Monitoring patients with hyperviscosity syndrome
This test is not useful for patients with small concentrations of monoclonal proteins.
Method Name
Capillary Measurement
Reporting Name
Viscosity, SSpecimen Type
Serum RedSpecimen Minimum Volume
0.75 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum Red | Refrigerated (preferred) | 28 days | |
Frozen | 28 days | ||
Ambient | 14 days |
Reject Due To
Gross hemolysis | OK |
Gross lipemia | OK |
Gross icterus | OK |
Clinical Information
Viscosity is the property of fluids to resist flow. Hyperviscosity may be manifested by nasal bleeding, blurred vision, headaches, dizziness, nystagmus, deafness, diplopia, ataxia, paresthesias, or congestive heart failure. Funduscopic examination reveals dilation of retinal veins and flame shaped retinal hemorrhages.
The most common cause of serum hyperviscosity is the presence of large concentrations of IgM monoclonal proteins, and Waldenstrom macroglobulinemia accounts for 80% to 90% of hyperviscosity cases. Hyperviscosity syndrome can also occur in multiple myeloma patients.
Because the ability of a monoclonal protein to cause hyperviscosity is affected by its concentration, molecular weight, and aggregation, sera with concentrations of monoclonal IgM greater than 4 g/dL, IgA greater than 5 g/dL, or IgG greater than 6 g/dL should be tested for hyperviscosity.
Serum viscosity and electrophoresis are recommended before and after plasmapheresis in order to correlate viscosity and M-spike with patient symptoms. This correlation may be useful for anticipating the need for repeat plasmapheresis.
Reference Values
≤1.5 centipoises
Interpretation
Although viscosities greater than 1.5 centipoises (cP) are abnormal, hyperviscosity is rarely present unless the viscosity is greater than 3 cP.
Day(s) Performed
Monday through Friday
Report Available
1 to 3 daysPerforming Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test has been modified from the manufacturer's instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
85810
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
SVISC | Viscosity, S | 3128-6 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
SVISC | Viscosity, S | 3128-6 |
Forms
If not ordering electronically, complete, print, and send 1 of the following forms with the specimen: