Immunoglobulin M (IgM) Heavy and Light Chain (HLC) Pairs, κ and λ With Ratio

CPT: 83883(x2)
Print Share

Test Details


  • Hevylite IgM
  • HLC IgM
  • IgM κ:λ HLC Ratio


For the quantitative measurement of human IgM heavy chain and light chain intact immunoglobulin in serum. The test result is to be used with previously diagnosed Waldenström's macroglobulinemia in conjunction with other clinical and laboratory findings. This assay has not been established for the diagnosis, monitoring, and prognosis of Waldenström's macroglobulinemia.

Heavy and light chain pair quantitation may be useful for:

1. Distinguishing between broadly migrating monoclonal proteins and restricted polyclonal immunoglobulin patterns on serum protein electrophoresis.

2. Quantitating monoclonal IgM proteins that are difficult to quantitate using serum protein electrophoresis alone.

3. Providing a more specific quantitation of the monoclonal protein than total IgM measurements alone.


Decisions on patient evaluation and management must not be given on the basis of IgM κ, IgM λ, or IgM κ:IgM λ ratio measurements alone. Clinical history and other laboratory findings must be taken into account.

Heavy and light chain (HLC) quantitation should be used as a complementary method to serum protein electrophoresis.

The effect of therapeutic drugs on the measurement of IgM κ and IgM λ by this assay has not been evaluated.

Small increases in the concentrations of monoclonal IgM proteins may not result in an altered HLC pair ratio.

For initial detection of monoclonal proteins, see:

Immunofixation (IFE), Serum and Protein Electrophoresis, Serum [001495]

Immunofixation (IFE), Serum, Protein Electrophoresis (PE), Serum, and Quantitative Free κ and λ Light Chains (FLC) Plus Ratio, Serum [120256]

Immunofixation (IFE) and Protein Electrophoresis, 24-Hour Urine [003467]



Reference Interval

• IgM κ (g/L): 0.29−1.82

• IgM λ (g/L): 0.17−0.94

• IgM κ:IgM λ ratio: 0.96−2.30

An elevated IgM heavy and light chain (HLC) pair ratio suggests a clonal proliferation of an IgM κ clone of plasma cells.

A low IgM HLC pair ratio suggests a clonal proliferation of an IgM λ clone of plasma cells.

Additional Information

Elevated serum concentrations of monoclonal protein are indicative of an underlying abnormality, such as monoclonal gammopathy of undetermined significance (MGUS), multiple myeloma, Waldenström's macroglobulinemia and other lymphoproliferative disorders. Serum protein electrophoresis (SPE) densitometry is recommended to quantify monoclonal proteins.1

Nephelometry can also be used in these instances to measure total IgM, but this will include nontumor immunoglobulin, and measurement of either IgM κ or IgM λ may provide additional information regarding tumor production.

Specimen Requirements




0.75 mL

Minimum Volume

0.5 mL


Red-top tube or gel-barrier tube

Patient Preparation

Patient should be fasting for eight hours to avoid lipemic sample interference.


Separate serum immediately after coagulation (30 minutes) to prevent hemolysis.

Storage Instructions


Stability Requirements



Room temperature

7 days


7 days


7 days

Freeze/thaw cycles

Stable x2

Causes for Rejection

Microbially-contaminated specimen; specimen containing particulate matter; lipemic or hemolyzed specimen

Clinical Information


1. Kyle RA, Rajkumar SV. Monoclonal gammopathies of undetermined significance: A review.Immunol Rev. 2003 Aug; 194:112-139. 12846812


Order Code Order Code Name Order Loinc Result Code Result Code Name UofM Result LOINC
123560 IgM Heavy Light Chains(HLC), S 123537 IgM Kappa, S g/L 74866-5
123560 IgM Heavy Light Chains(HLC), S 123538 IgM Lambda, S g/L 74867-3
123560 IgM Heavy Light Chains(HLC), S 123539 IgM K/L HLC Ratio Ratio 74870-7

For Providers

Please login to order a test.


© 2018  Laboratory Corporation of America® Holdings and Lexi-Comp Inc. All Rights Reserved.

CPT Statement/Profile Statement

The LOINC® codes are copyright © 1994-2018, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee. Permission is granted in perpetuity, without payment of license fees or royalties, to use, copy, or distribute the LOINC® codes for any commercial or non-commercial purpose, subject to the terms under the license agreement found at Additional information regarding LOINC® codes can be found at, including the LOINC Manual, which can be downloaded at