IgG4-related disease (IgG4-RD) is an increasingly recognized immune-mediated disorder that can affect almost every organ system and cause severe damage if left untreated [1-5]. Clinical and pathological hallmarks of IgG4-RD include elevated serum IgG4 concentration in most patients, an enriched IgG4+ plasma cells infiltrate in affected tissues, and a swift response to glucocorticoids [1,6].
