Tubulointerstitial immune complex nephritis in a patient with systemic lupus erythematosus: role of peritubular capillaritis with immune complex deposits in the pathogenesis of the tubulointerstitial nephritis.
Class IV-G (A/C) diffuse lupus nephritis and tubulointerstitial (TI) nephritis in a 31-year old woman was studied by light, immunofluorescence (IF), and electron microscopy (EM), to determine the pathogenesis of the TI lesions. The light microscopic findings showed peritubular capillaritis in the interstitium, with ruptures in the capillary structure, lysis of the surrounding tubular basement membrane (TBM), extravasated red blood cells (RBCs), the infiltration of neutrophils and mononuclear cells, and edema. The IF study revealed IgG, IgA, IgM, C1q, C3, and C4 depositions along the TBM, on the capillary walls, and in the interstitium proper. The EM study disclosed the deposition of immune complexes in the TBM, the capillary wall, and the interstitium proper. Based on these findings, the TI nephritis in this patient was considered to be due to peritubular capillaritis secondary to the immune complex depositions in the capillary wall of the interstitium.
Hayakawa
Satoshi
S
First Department of Internal Medicine, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo 181-0086, Japan.
Nakabayashi
Kimimasa
K
Karube
Miho
M
Arimura
Yoshihiro
Y
Arimura
Yoshiro
Y
Soejima
Akinori
A
Yamada
Akira
A
Fujioka
Yasunori
Y
D000328:Adult; D000936:Antigen-Antibody Complex / Q000032:analysis; D001485:Basement Membrane / Q000737:chemistry; D001706:Biopsy; D002196:Capillaries / Q000737:chemistry / Q000473:pathology; D005260:Female; D006801:Humans; D007684:Kidney Tubules / Q000098:blood supply; D008180:Lupus Erythematosus, Systemic / Q000150:complications* / Q000473:pathology; D008775:Methylprednisolone / Q000627:therapeutic use; D008854:Microscopy, Electron; D008856:Microscopy, Fluorescence; D009395:Nephritis, Interstitial / Q000209:etiology* / Q000473:pathology; D011239:Prednisolone / Q000627:therapeutic use; D020551:Pulse Therapy, Drug
D000936:Antigen-Antibody Complex; D011239:Prednisolone; D008775:Methylprednisolone