AJKD Atlas of Renal Pathology: IgG4-Related Tubulointerstitial Nephritis

IgG4-related disease is an immune-mediated systemic condition characterized by presence of discrete mass lesions or diffuse infiltrative lesions in organs, composed of lymphoproliferative infiltrates including frequent IgG4-producing plasma cells and variable storiform fibrosis. Serum levels of IgG4 are increased (>135mg/dL) in ∼2/3 of patients. It is more common in middle-aged and older men. In 60-90% of patients, multiple organs/sites are involved. The most common sites include pancreas, biliary tract, salivary or lacrimal glands, orbits, retroperitoneum, and kidneys.