title: Renal amyloidosis: origin and clinicopathologic correlations of 474 recent cases.
abstract: OBJECTIVE
  The kidney is the organ most commonly involved in systemic amyloidosis. This study reports the largest clinicopathologic series of renal amyloidosis.
  
  
  METHODS
  This study provides characteristics of 474 renal amyloidosis cases evaluated at the Mayo Clinic Renal Pathology Laboratory from 2007 to 2011, including age, sex, serum creatinine, proteinuria, type of amyloid, and tissue distribution according to type.
  
  
  RESULTS
  The type of amyloid was Ig amyloidosis in 407 patients (85.9%), AA amyloidosis in 33 (7.0%), leukocyte chemotactic factor 2 amyloidosis in 13 (2.7%), fibrinogen A α chain amyloidosis in 6 (1.3%), Apo AI, Apo AII, or Apo AIV amyloidosis in 3 (0.6%), combined AA amyloidosis/Ig heavy and light chain amyloidosis in 1 (0.2%), and unclassified in 11 (2.3%). Laser microdissection/mass spectrometry, performed in 147 cases, was needed to determine the origin of amyloid in 74 of the 474 cases (16%), whereas immunofluorescence failed to diagnose 28 of 384 light chain amyloidosis cases (7.3%). Leukocyte chemotactic factor 2 amyloidosis and Apo AI, Apo AII, or Apo AIV amyloidosis were characterized by diffuse interstitial deposition, whereas fibrinogen A α chain amyloidosis showed obliterative glomerular involvement. Compared with other types, Ig amyloidosis was associated with lower serum creatinine, higher degree of proteinuria, and amyloid spicules.
  
  
  CONCLUSIONS
  In the authors' experience, the vast majority of renal amyloidosis cases are Ig derived. The newly identified leukocyte chemotactic factor 2 amyloidosis form was the most common of the rarer causes of renal amyloidosis. With the advent of laser microdissection/mass spectrometry for amyloid typing, the origin of renal amyloidosis can be determined in >97% of cases.
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA. nasr.samih@mayo.edu
authors.forename: Samar M
authors.initials: SM
authors.lastname: Said
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Sethi
authors.forename: Anthony M
authors.initials: AM
authors.lastname: Valeri
authors.forename: Nelson
authors.initials: N
authors.lastname: Leung
authors.forename: Lynn D
authors.initials: LD
authors.lastname: Cornell
authors.forename: Mary E
authors.initials: ME
authors.lastname: Fidler
authors.forename: Loren
authors.initials: L
authors.lastname: Herrera Hernandez
authors.forename: Julie A
authors.initials: JA
authors.lastname: Vrana
authors.forename: Jason D
authors.initials: JD
authors.lastname: Theis
authors.forename: Patrick S
authors.initials: PS
authors.lastname: Quint
authors.forename: Ahmet
authors.initials: A
authors.lastname: Dogan
authors.forename: Samih H
authors.initials: SH
authors.lastname: Nasr
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000682:Amyloid / Q000032:analysis*; D000686:Amyloidosis / Q000150:complications / Q000473:pathology*; D016632:Apolipoprotein A-I / Q000032:analysis; D016633:Apolipoprotein A-II / Q000032:analysis; D001054:Apolipoproteins A / Q000032:analysis; D001706:Biopsy; D002648:Child; D003404:Creatinine / Q000097:blood; D005260:Female; D005340:Fibrinogen / Q000032:analysis; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000032:analysis; D007147:Immunoglobulin Light Chains / Q000032:analysis; D036341:Intercellular Signaling Peptides and Proteins / Q000032:analysis; D007674:Kidney Diseases / Q000150:complications / Q000473:pathology*; D008297:Male; D013058:Mass Spectrometry; D042282:Microdissection; D008875:Middle Aged; D011507:Proteinuria / Q000150:complications; D055815:Young Adult
chemical_list: D000682:Amyloid; D016632:Apolipoprotein A-I; D016633:Apolipoprotein A-II; D001054:Apolipoproteins A; D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D036341:Intercellular Signaling Peptides and Proteins; C103468:LECT2 protein, human; C022205:apolipoprotein A-IV; C464794:fibrinogen Aalpha; D005340:Fibrinogen; D003404:Creatinine