Does truly 'idiopathic' crescentic glomerulonephritis exist?
Crescentic glomerulonephritis is usually classified into antiglomerular basement membrane (GBM) disease, immune-complex disease, or pauci-immune crescentic nephritis. The last category includes patients with systemic vasculitis as well as 'idiopathic' isolated crescentic nephritis. The presence of anti-neutrophil cytoplasmic antibodies (ANCA) in many patients with apparently isolated crescentic nephritis suggests that this represents a renal-limited form of vasculitis, and that truly 'idiopathic' crescentic nephritis is a very rare entity. We reviewed all renal biopsies with extracapillary proliferation seen at our centre since the availability of an ANCA assay (4-year period). There were 89 such biopsies of a total of 1240, of which 82 had sufficient details for further analysis. Of these, 10 had anti-GBM disease, 35 had epithelial proliferation associated with a variety of other diseases, and 36 had ANCA-associated disease. Nine of this last group had no extrarenal features and would previously have been classified as 'idiopathic' crescentic glomerulonephritis. The single remaining patient had an inactive glomerulonephritis with a scarred crescent; the predominant lesion was an interstitial nephritis. We therefore conclude that truly 'idiopathic' crescentic nephritis is very rare, if it exists at all. The ability to provide a practically complete classification of crescentic nephritis has important prognostic and therapeutic consequences.
Department of Medicine, University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, UK.
R
R
Angangco
S
S
Thiru
V L
VL
Esnault
A K
AK
Short
C M
CM
Lockwood
D B
DB
Oliveira
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019268:Antibodies, Antineutrophil Cytoplasmic; D001323:Autoantibodies / Q000032:analysis* / Q000097:blood; D015415:Biomarkers / Q000032:analysis; D001706:Biopsy; D003937:Diagnosis, Differential; D005260:Female; D005921:Glomerulonephritis / Q000145:classification / Q000276:immunology / Q000473:pathology*; D006801:Humans; D007105:Immune Complex Diseases / Q000097:blood / Q000276:immunology / Q000473:pathology*; D007678:Kidney Glomerulus / Q000098:blood supply / Q000276:immunology / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000276:immunology; D014657:Vasculitis / Q000276:immunology / Q000473:pathology
D019268:Antibodies, Antineutrophil Cytoplasmic; D001323:Autoantibodies; D015415:Biomarkers