| A rare renal disease occurring in the setting of a systemic IgG4 (immunoglobulin G4) related disease. The disorder has characteristics of fibrosing tubulointerstitial nephritis consisting of predominantly IgG4 positive plasma cells with/without glomerulonephritis, mass lesions, enlarged kidneys and hydronephrosis. Other extra renal manifestations of IgG4 related disease may also be present (e.g. salivary glands, hepatobiliary system, lungs). |
