An overlapping case of IgG4-related disease and systemic lupus erythematosus treated with belimumab: a case-based review

Rheumatol Int. 2024 Mar;44(3):549-556. doi: 10.1007/s00296-023-05510-3. Epub 2024 Jan 3.


IgG4-related disease (IgG4-RD) is a systemic condition in which IgG4+ plasma cell infiltration and fibrosis cause organ swelling and lead to diverse clinical manifestations. Although IgG4-RD typically responds to glucocorticoids (GCs), relapse during tapering occurs and an early GC-sparing approach might therefore be beneficial. Systemic lupus erythematosus (SLE) is a chronic inflammatory disease with multiple symptoms that is also treated with GCs as a first-line therapy. Recently, belimumab, a recombinant human IgG-1λ monoclonal antibody that inhibits B-cell activating factor, was approved, but reports of use for IgG4-RD are scarce. Here, we present a rare case of IgG4-RD complicated with SLE which was successfully treated with belimumab. A 67-year-old man was diagnosed with IgG4-RD based on a high serum IgG4 level and histopathological findings. Furthermore, he had pericardial effusion on echocardiography, and laboratory tests revealed thrombocytopenia, autoimmune hemolysis, positive anti-nuclear antibodies, positive anti-DNA antibodies, and hypocomplementemia. These data led to an SLE diagnosis. Treatment was started with prednisolone at 40 mg/day, plus hydroxychloroquine, which initially improved both the SLE and IgG4-RD symptoms. During the GC tapering, belimumab was added and clinical symptoms resolved completely. Our case and the literature review summarize reported rare overlapping cases of IgG4-RD and SLE and suggest that belimumab is a promising candidate for the treatment of IgG4-RD.

Keywords: Belimumab; IgG4-related disease; Systemic lupus erythematosus.

Publication types

  • Case Reports
  • Review

MeSH terms

  • Aged
  • Antibodies, Monoclonal / therapeutic use
  • Antibodies, Monoclonal, Humanized / therapeutic use
  • Glucocorticoids / therapeutic use
  • Humans
  • Immunoglobulin G
  • Immunoglobulin G4-Related Disease* / complications
  • Immunoglobulin G4-Related Disease* / diagnosis
  • Immunoglobulin G4-Related Disease* / drug therapy
  • Immunosuppressive Agents / therapeutic use
  • Lupus Erythematosus, Systemic* / complications
  • Lupus Erythematosus, Systemic* / diagnosis
  • Lupus Erythematosus, Systemic* / drug therapy
  • Male
  • Treatment Outcome


  • belimumab
  • Antibodies, Monoclonal, Humanized
  • Antibodies, Monoclonal
  • Glucocorticoids
  • Immunoglobulin G
  • Immunosuppressive Agents