title: A case of renal sarcoidosis with complement activation via the lectin pathway.
abstract: A 57-year-old woman with pulmonary sarcoidosis was admitted to the hospital because of an elevation of serum creatinine and blood urea nitrogen. On admission, the laboratory data suggested interstitial nephritis without proteinuria and hematuria, whereas a renal biopsy showed granulomatous interstitial nephritis and mild mesangial proliferative glomerulonephritis. Immunoglobulin and C1q deposits were negative, but mannose-binding lectin, C3, C4d, and C5b-9 deposits were marked in the glomerular mesangial areas. The lectin pathway of complement activation may have contributed to the development of glomerular injury in this patient. DNA of Propionibacterium acnes , which is now strongly suspected as the pathogen of sarcoidosis, was detected in the patient's glomerular mesangial cells; tubular epithelial cells, which were involved in granulomatous inflammation; and mononuclear cells in epithelioid granulomas by in situ hybridization. These findings may add new insights to the pathogenesis of renal sarcoidosis, including its relation to infection, because mannose-binding lectin plays a crucial role in the host defense against various pathogens. From this case of renal sarcoidosis, it is hypothesized that P acnes may be involved in pathogenesis of granulomatous interstitial nephritis and that it plays a role in glomerular complement activation via the lectin pathway.
authors.affiliation: Division of Nephrology, Department of Internal Medicine, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Hagiwara
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ohi
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Eishi
authors.forename: Fumiko
authors.initials: F
authors.lastname: Kodama
authors.forename: Kyoichi
authors.initials: K
authors.lastname: Tashiro
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Makita
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Kunimi
authors.initials: K
authors.lastname: Maeda
authors.forename: Mitsumine
authors.initials: M
authors.lastname: Fukui
authors.forename: Satoshi
authors.initials: S
authors.lastname: Horikoshi
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Tomino
mesh_terms: D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D000925:Anticoagulants / Q000627:therapeutic use; D003167:Complement Activation; D003176:Complement C3 / Q000032:analysis; D015935:Complement C4b / Q000032:analysis; D015938:Complement Membrane Attack Complex / Q000032:analysis; D004269:DNA, Bacterial / Q000032:analysis; D004359:Drug Therapy, Combination; D005260:Female; D005920:Glomerular Mesangium / Q000737:chemistry / Q000382:microbiology / Q000473:pathology; D015432:Glomerulonephritis, Membranoproliferative / Q000188:drug therapy / Q000209:etiology / Q000276:immunology* / Q000382:microbiology; D016908:Gram-Positive Bacterial Infections / Q000150:complications / Q000382:microbiology; D006493:Heparin / Q000627:therapeutic use; D006646:Histiocytosis, Langerhans-Cell / Q000150:complications / Q000188:drug therapy / Q000276:immunology; D006801:Humans; D008168:Lung / Q000473:pathology; D017563:Lung Diseases, Interstitial / Q000150:complications / Q000188:drug therapy / Q000276:immunology; D037601:Mannose-Binding Lectin / Q000032:analysis*; D008775:Methylprednisolone / Q000627:therapeutic use; D008875:Middle Aged; D009395:Nephritis, Interstitial / Q000188:drug therapy / Q000209:etiology / Q000276:immunology* / Q000382:microbiology; D010446:Peptide Fragments / Q000032:analysis; D011241:Prednisone / Q000627:therapeutic use; D011425:Propionibacterium acnes / Q000302:isolation & purification / Q000472:pathogenicity*; D012507:Sarcoidosis / Q000188:drug therapy / Q000209:etiology / Q000276:immunology* / Q000382:microbiology; D014859:Warfarin / Q000627:therapeutic use
chemical_list: D000893:Anti-Inflammatory Agents; D000925:Anticoagulants; D003176:Complement C3; D015938:Complement Membrane Attack Complex; D004269:DNA, Bacterial; D037601:Mannose-Binding Lectin; D010446:Peptide Fragments; D014859:Warfarin; D015935:Complement C4b; C032261:complement C4d; D006493:Heparin; D011241:Prednisone; D008775:Methylprednisolone