The clinicopathologic characteristics of kidney diseases related to monotypic IgA deposits

Kidney Int. 2017 Mar;91(3):720-728. doi: 10.1016/j.kint.2016.10.026. Epub 2017 Jan 6.

Abstract

Monoclonal gammopathy of renal significance (MGRS) regroups renal disorders caused by a monoclonal immunoglobulin without overt hematological malignancy. MGRS includes tubular disorders, glomerular disorders with organized deposits, and glomerular disorders with non-organized deposits, such as proliferative glomerulonephritis with monoclonal IgG deposits. Since glomerular involvement related to monotypic IgA deposits is poorly described we performed retrospective analysis and defined clinico-biological characteristics, renal pathology, and outcome in 19 referred patients. This analysis allowed distinction between 2 types of glomerulopathies, α-heavy chain deposition disease (5 patients) and glomerulonephritis with monotypic IgA deposits (14 patients) suggestive of IgA-proliferative glomerulonephritis with monoclonal immunoglobulin deposits in 12 cases. Clinicopathologic characteristics of α-heavy chain deposition disease resemble those of the γ-heavy chain disease, except for a higher frequency of extra-capillary proliferation and extra-renal involvement. IgA-proliferative glomerulonephritis with monoclonal immunoglobulin deposits should be differentiated from diseases with polytypic IgA deposits, given distinct clinical, histological, and pathophysiological features. Similarly to IgG-proliferative glomerulonephritis with monoclonal immunoglobulin deposits, overt hematological malignancy was infrequent, but sensitive serum and bone marrow studies revealed a subtle plasma cell proliferation in most patients with IgA-proliferative glomerulonephritis with monoclonal immunoglobulin deposits. Anti-myeloma agents appeared to favorably influence renal prognosis. Thus, potential progression towards symptomatic IgA multiple myeloma suggests that careful hematological follow-up is mandatory. This series expands the spectrum of renal disease in MGRS.

Keywords: glomerular disease; monoclonal IgA deposits; monoclonal gammopathy of renal significance.

Publication types

  • Multicenter Study

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Biomarkers / analysis
  • Biopsy
  • Cell Proliferation
  • Diagnosis, Differential
  • Disease Progression
  • Female
  • Fluorescent Antibody Technique
  • France
  • Glomerulonephritis / drug therapy
  • Glomerulonephritis / immunology*
  • Glomerulonephritis / pathology
  • Glomerulonephritis, IGA / drug therapy
  • Glomerulonephritis, IGA / immunology*
  • Glomerulonephritis, IGA / pathology
  • Heavy Chain Disease / drug therapy
  • Heavy Chain Disease / immunology*
  • Heavy Chain Disease / pathology
  • Humans
  • Immunoglobulin A / analysis*
  • Immunoglobulin alpha-Chains / analysis
  • Immunoglobulin gamma-Chains / analysis
  • Kidney / drug effects
  • Kidney / immunology*
  • Kidney / ultrastructure
  • Male
  • Middle Aged
  • Multiple Myeloma / drug therapy
  • Multiple Myeloma / immunology*
  • Multiple Myeloma / pathology
  • Predictive Value of Tests
  • Prognosis
  • Retrospective Studies
  • Time Factors

Substances

  • Biomarkers
  • Immunoglobulin A
  • Immunoglobulin alpha-Chains
  • Immunoglobulin gamma-Chains
  • heavy chain disease proteins, human