Analysis of patients with γ-heavy chain disease by the heavy/light chain and free light chain assays

Clin Chem Lab Med. 2014 May;52(5):665-9. doi: 10.1515/cclm-2013-0714.


Background: The objective of this study was to evaluate the performance of the heavy/light chain and free light chain immunoassays in patients with heavy chain disease, and to assess the ability of the heavy/light chain assay to measure and confirm the abnormal, truncated heavy chain.

Methods: Frozen serum samples from 15 γ-heavy chain disease patients were tested for IgGκ, IgGλ, total IgG, free light chains, and M-spike concentrations.

Results: The (Gκ+Gλ)/IgGtotal ratio for these 15 patients ranged from 0.02 to 0.80. The 10 patients with IgG concentrations above 1 g/dL all had ratios below 0.3 indicating that a substantial portion of IgG was not quantitated by the Gκ and Gλ reagents. The average M-spike was 1.61 g/dL and the average calculated abnormal γ-chain concentration was 2.94 g/dL. Additionally, free light chain analysis revealed the presence of monoclonal free κ light chain in three of the 15 patients.

Conclusions: This study demonstrates utility of a nephelometric assay to identify truncated immunoglobulin heavy chains in γ-HCD and that 20% of these patients also have monoclonal free light chain.

MeSH terms

  • Electrophoresis
  • Heavy Chain Disease / metabolism
  • Heavy Chain Disease / pathology
  • Humans
  • Immunoassay*
  • Immunoglobulin Heavy Chains / blood*
  • Immunoglobulin Light Chains / blood*
  • Immunoglobulin kappa-Chains / blood
  • Immunoglobulin lambda-Chains / blood


  • Immunoglobulin Heavy Chains
  • Immunoglobulin Light Chains
  • Immunoglobulin kappa-Chains
  • Immunoglobulin lambda-Chains