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CPT: 85810
Updated on 10/11/2020
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  • Serum Viscosity

Expected Turnaround Time

2 - 5 days

Related Documents

Specimen Requirements




1 mL

Minimum Volume

0.5 mL (Note: This volume does not allow for repeat testing.)


Red-top tube or gel-barrier tube

Storage Instructions




Stability Requirements




14 days

Causes for Rejection

Hemolysis; fibrin clots; quantity not sufficient for analysis

Test Details


Evaluate hyperviscosity syndrome associated with monoclonal gammopathy states (myeloma, macroglobulinemia of Waldenström, and other dysproteinemias), including occasional cases of rheumatoid arthritis, SLE, systemic lupus erythematosus, hyperfibrinogenemia


This test was developed, and its performance characteristics determined, by LabCorp. It has not been cleared or approved by the Food and Drug Administration.



Reference Interval

• 0 to 5 years: Not established

• 6 to 50 years: 1.4−2.0 relative to saline

• >50 years: 1.4−2.1 relative to saline

Values >2.7 may indicate paraproteinemia is present.

1.6−1.9 relative to saline (values >2.7 may indicate paraproteinemia is present)

• 0 to 5 years: Not established

• 6 to 50 years: 1.4−2.0 relative to saline

• >50 years: 1.4−2.1 relative to saline

Values >2.7 may indicate paraproteinemia is present.

Additional Information

Hyperviscosity most frequent (33% of cases)1 with IgM monoclonal gammopathy (Waldenström macroglobulinemia); next with IgA myeloma. When IgG myeloma leads to hyperviscosity, IgG levels are usually very significantly elevated. A relative viscosity of 6−7 usually results in symptoms of the hyperviscosity syndrome, they have however been described with lower levels of relative viscosity (ie, 4).2 Neonatal hyperviscosity, usually but not always associated with polycythemia, may be accompanied by a fairly typical clinical picture. Plethora, hypoglycemia, lethargy, and jitteriness/seizures (CNS symptoms) occur. There may be symptoms and findings suggesting congenital heart disease (CHD) (ie, respiratory distress, cardiac enlargement, and cyanosis). False diagnoses of CHD have been made in such cases. About 50% of such infants have modest hyperbilirubinemia (bilirubin >12 mg/dL).


1. Gandara DR, MacKenzie MR. Differential diagnosis of monoclonal gammopathy. Med Clin North Am. 1988; 72(5):1155-1167 (review). 3137401
2. Fahey JL, Barth WF, Solomon A. Serum hyperviscosity syndrome. JAMA. 1965; 192:464-467.14284847


Order Code Order Code Name Order Loinc Result Code Result Code Name UofM Result LOINC
004861 Viscosity, Serum 3128-6 004863 Viscosity, Serum rel.saline 3128-6

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