Immunoglobulin G4-Related Bilateral Kidney Disease

Abstract

Immunoglobulin G4-related disease (IgG4-RD) is uncommon and is characterized by dense tissue infiltration of IgG4-positive plasma cells or mass-like sclerosing lesions. In addition, it can involve any anatomic site, which has frequently elevated serum IgG4 concentrations. Japanese gastroenterologists are the ones who first discussed the concept of IgG4-RD; they first introduced the term IgG4-related kidney disease (IgG4-RKD), which refers to the involvement of the kidney and its surrounding tissues. Common urologic indicators of IgG4-RKD typically include subacute pain, on the detection of a tumor-like mass or enlargement, with or without tubulointerstitial nephritis. Conventional imaging computed tomography and magnetic resonance imaging are of limited usefulness in determining IgG4-RKD. The gold-standard for the diagnosis of IgG4-RD is the identification of typical histopathological features of dense lymphoplasmacytic infiltration, storiform fibrosis (an irregular cartwheel like fibrotic pattern), and obliterative phlebitis; these are the three hallmarks of IgG4-RD. The current report discusses a case of IgG4-RKD, who came into our hospital with chronic flank pain.