title: Does the presence of ANCA in patients with ulcerative colitis necessarily imply renal involvement?
abstract: BACKGROUND
  ANCA are thought to play a pathogenic role in renal vasculitis. ANCA may also be detected in patients with diseases not usually associated with renal pathology, such as ulcerative colitis. Our study was conducted to determine if the presence of ANCA in patients with ulcerative colitis is associated with renal pathology.
  
  
  METHODS
  Eight ANCA-positive and five ANCA-negative patients with a histological and endoscopic diagnosis of active ulcerative colitis were investigated. Repeated complete urinalyses and determination of microalbuminuria and creatinine clearance were performed. Serum IgG and IgA ANCA were evaluated in all patients by indirect immunofluorescence and ELISA, and when detected the antibodies were further characterized by alpha granules preparation, myeloperoxidase, lactoferrin, and cathepsin G.
  
  
  RESULTS
  In both ANCA-positive and ANCA-negative patients renal function was normal or near normal and urinalyses (including microalbuminuria) failed to disclose any abnormalities. ANCA exhibited a perinuclear pattern in all ANCA-positive patients. Interestingly, none of the ANCA-positive patients had antibodies to myeloperoxidase or to alpha granules which are usually found in the sera of patients with ANCA-associated vasculitis, and only one had antibodies to lactoferrin. The ANCA specificity remained undetermined in the remaining seven patients. At the end of the 1-year observation period, all ANCA-positive patients remained ANCA-positive without developing symptoms, signs or laboratory abnormalities consistent with renal involvement.
  
  
  CONCLUSIONS
  Renal damage was not observed in ANCA-positive patients with ulcerative colitis even after 1 year of follow-up, suggesting that the ANCA found in these patients do not share the antigenic targets with the ANCA commonly found in renal vasculitis. Therefore the potential of ANCA of inducing renal lesions (if any) is dependent on their own antigenic specificity.
authors.affiliation: Chairs of Nephrology, Faculty of Medicine of Catanzaro, Ospedale San Carlo, Milano, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Rosa
authors.forename: C
authors.initials: C
authors.lastname: Esposito
authors.forename: A
authors.initials: A
authors.lastname: Caglioti
authors.forename: G
authors.initials: G
authors.lastname: Mazza
authors.forename: M
authors.initials: M
authors.lastname: Capria
authors.forename: N
authors.initials: N
authors.lastname: Comi
authors.forename: G
authors.initials: G
authors.lastname: Monteleone
authors.forename: R A
authors.initials: RA
authors.lastname: Sinico
authors.forename: G
authors.initials: G
authors.lastname: Fuiano
mesh_terms: D000293:Adolescent; D000328:Adult; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood*; D003093:Colitis, Ulcerative / Q000097:blood* / Q000276:immunology; D003404:Creatinine / Q000652:urine; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007668:Kidney / Q000098:blood supply* / Q000276:immunology / Q000502:physiology; D008297:Male; D008875:Middle Aged; D014657:Vasculitis / Q000097:blood* / Q000276:immunology
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D003404:Creatinine