Authors: Son D, Kanda H, Yamaguchi A, Kawabata K, Kawakami T, Kubo K, Higashihara M, Shimizu J, Uozaki H, Kuramochi S, Misaki Y, Takeuchi F, Yamamoto K
Renal involvement in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is characterized by focal segmental crescentic and/or necrotizing glomerulonephritis. Here, we report the case of a 66-year-old woman showing myeloperoxidase (MPO)-ANCA positivity and mononeuritis multiplex whose kidney biopsy revealed severe and diffuse tubulointerstitial nephritis despite the fact that crescentic necrotizing glomerulonephritis was focal. The mechanism of tubulointerstitial injury in ANCA-associated vasculitis remains unclear. Further studies are necessary to confirm the relationship between diffuse tubulointerstitial nephritis and AN...