IgG4 related sclerosing disease with multiple organ involvements and response to corticosteroid treatment.

Great attention has been drawn toward the recently defined IgG4 related sclerosing disease, an entity incorporating autoimmune pancreatitis and other organ involvements, hypergammaglobulinemia and deposition of IgG4 in affected tissues. We demonstrate an index case of this disease with multiple organ involvements and an excellent response to corticosteroid treatment. A 69-year-old white man was diagnosed with IgG4 related sclerosing disease with involvement of lungs, pancreas, submandibular glands, lymph nodes, and kidney. In addition, the patient had polyclonal IgG hypergammaglobulinemia and hypocomplementemia. A renal biopsy showed tubulointerstitial nephritis with extensive lymphoplasmacytic infiltrate. Biopsy of the lung showed "inflammatory pseudotumor" with lymphocyte and plasma cell infiltration. IgG4 positive plasma cells were seen in the biopsy of submandibular gland and the kidney. Immuno-staining of the renal biopsy specimen showed vascular deposition of complement split product C4d. Corticosteroid treatment of 2 months showed complete resolution of the disease process. We demonstrate deposition of C4d in the IgG4 related tubulointerstitial nephritis for the first time.