title: Prevalence of histological beta2-microglobulin amyloidosis in CAPD patients compared with hemodialysis patients.
abstract: BACKGROUND
  The prevalence of beta2-microglobulin amyloidosis (Abeta2m) in patients on continuous ambulatory peritoneal dialysis (CAPD) is unknown.
  
  
  METHODS
  We prospectively obtained a median of 2 (range 1 to 4) joint samples from 26 CAPD patients aged 44 to 93 (median 73) years at post-mortem evaluation after 4.5 to 126 (median 27) months solely on CAPD (N = 19) or primarily on CAPD (that is, < or = 10% and < or = 1 year of renal replacement therapy time on other modalities; N = 7). The diagnosis of Abeta2m rested on Congo red staining (typical birefringence) and positive immunostaining of amyloid deposits by a monoclonal anti-beta2m antibody.
  
  
  RESULTS
  Abeta2m was diagnosed in 8 of 26 patients (31%). Prevalence ranged from 20% (2 of 10 patients) within < or = 24 months CAPD to 30% (3 of 10 patients) after 24 to 48 months and 50% (3 of 6 patients) after 49 to 126 months (P = 0.11). The prevalence of Abeta2m was similar in patients without or with one or more peritonitis episodes. No significant difference in prevalence (P = 0.118) was found between CAPD patients (8+/26; 31%) and hemodialysis patients (13+/26; 50%) carefully matched for time on dialysis and age at the onset of dialysis.
  
  
  CONCLUSIONS
  The prevalence of histological Abeta2m reaches 31% after a median duration of 27 months of CAPD. This prevalence is not significantly different from that observed in a group of HD patients matched for age and dialysis duration.
authors.affiliation: Department of Nephrology, Cliniques Universitaires St-Luc, Brussels, Belgium. Jadoul@nefr.ucl.ac.be
authors.forename: M
authors.initials: M
authors.lastname: Jadoul
authors.forename: C
authors.initials: C
authors.lastname: Garbar
authors.forename: R
authors.initials: R
authors.lastname: Vanholder
authors.forename: J
authors.initials: J
authors.lastname: Sennesael
authors.forename: C
authors.initials: C
authors.lastname: Michel
authors.forename: A
authors.initials: A
authors.lastname: Robert
authors.forename: H
authors.initials: H
authors.lastname: Noël
authors.forename: C
authors.initials: C
authors.lastname: van Ypersele de Strihou
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000686:Amyloidosis / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010531:Peritoneal Dialysis, Continuous Ambulatory / Q000009:adverse effects*; D015995:Prevalence; D011446:Prospective Studies; D006435:Renal Dialysis / Q000009:adverse effects*; D001613:beta 2-Microglobulin / Q000378:metabolism*
chemical_list: D001613:beta 2-Microglobulin