Coexistence of IgG4-Related Disease and Reactive Granuloma to Paraffin Plombage.

We present a patient with IgG4-related disease (IgG4-RD) that developed after receiving extra-periosteal paraffin-embedded therapy for the treatment of pulmonary tuberculosis. The patient showed clinicopathological features consistent with IgG4-RD, including the enlargement of affected organs (salivary glands, lymph nodes, and retroperitoneal soft tissue mass), elevation of serum IgG4 levels, and infiltration of IgG4-positive plasma cells. The presence of reactive granulomas with foreign body giant cells (FBGCs) surrounding the paraffin-filled site suggested a type 2 helper T (Th2)-dominant immune response induced by the implanted biomaterial. Furthermore, paraffin, known to act as an adjuvant, may have played a role in activating the immune response and inducing IgG4-RD-like symptoms. This case highlights the potential relationship between foreign substances and the development of autoimmune diseases such as IgG4-RD.