IgG4-Related Tubulointerstitial Nephritis Accompanied by Henoch-Schonlein Purpura / 대한내과학회지

ABSTRACT

Tubulointerstitial nephritis is one of the common manifestations of immunoglobulin G (IgG)4-related disease; however, among all cases of tubulointerstitial nephritis undergoing renal biopsies, IgG4-related tubulointerstitial nephritis seems to be relatively rare because of its trivial urinary findings. A previously healthy 54-year-old man was referred to our clinic with a 4-week history of lower leg purpura and renal dysfunction. A kidney biopsy was planned because of bilateral renomegaly, by imaging studies, and elevated serum creatinine levels. Pathological findings in the kidney showed prominent infiltration of IgG4-postive plasma cells in the tubulointerstitium, but not the glumeruli. A skin biopsy revealed leukocytoclastic vasculitis, accompanied by deposition of IgA and C3 in the vascular wall, indicating Henoch-Schonlein purpura (HSP). Although cases of combined IgG4-related disease and microvasculitis, including HSP, are extremely rare, the possibility of an association between two diseases deserves attention.