By Dr Sophie Mavrogeni, Dr George Markousis-Mavrogenis & Dr Genovefa Kolovou
Immunoglobulin 4-related disease (IgG4-related disease) is a systemic inflammatory disease characterized by an increase in serum levels of IgG4 and by fibrosclerosis, lymphocytic infiltration and IgG4-positive plasma cells. Assay of serum IgG4 levels and biopsy of involved organs are necessary for diagnosis. The disease usually responds to treatment with corticosteroids and/or immunosuppressive medication.