title: Serum total IgG and IgG4 levels in thyroid eye disease.
abstract: OBJECTIVE
  To investigate the relationship between immunoglobulin G (IgG)4-related disease (IgG4-RD) and thyroid eye disease (TED) with respect to IgG levels.
  
  
  METHODS
  A retrospective review of total IgG, IgG subclass, and thyroid stimulating immunoglobulin (TSI) levels in 24 patients with TED.
  
  
  RESULTS
  Five patients (20.8%) demonstrated serum IgG4 levels consistent with IgG4-RD without any additional systemic disease. Total IgG and IgG subclass levels were found to be an inadequate proxy for TSI elevation.
  
  
  CONCLUSIONS
  There may be a subtype of TED patients with elevated IgG4 in the absence of IgG4-RD systemic findings.
authors: Department of Ophthalmology, California Pacific Medical Center, San Francisco, CA, USA.
authors: Aileen
authors: A
authors: Sy
authors: Department of Ophthalmology, California Pacific Medical Center, San Francisco, CA, USA.
authors: Rona Z
authors: RZ
authors: Silkiss
keywords: Graves’ disease; Graves’ ophthalmopathy; IgG subclass; IgG4; IgG4-RD; thyroid eye disease