title: Distribution of amyloid deposits in the kidneys of a patient with reactive amyloidosis associated with rheumatoid arthritis.
abstract: BACKGROUND
  We previously reported that the amount of amyloid A (AA) amyloid deposited in renal biopsy specimens was highly correlated with parameters of renal function. However, the distribution of amyloid deposits throughout the kidneys of these patients, and the degree of renal abnormality, remained unclear. Therefore, we describe the features of reactive amyloidosis associated with rheumatoid arthritis (RA) in an autopsied patient.
  
  
  METHODS
  The present report case is a 50-year-old female with RA and reactive amyloidosis. She was diagnosed as RA in 1978. Diagnosis of AA amylodosis was made by renal biopsy in 1991 for the reason of proteinuria. Because of the pancreatitis, she was died in 2006 and autopsy was performed. Renal tissues from autopsy specimens were evaluated for their proportions of amyloid-positive areas. A total of 6 specimens (three tissue blocks from each kidney obtained at autopsy) were evaluated in this study. The size of each block was approximately 20 mm × 20 mm. One section of whole tissue was photographed in each case. The borders of the amyloid-positive areas in each specimen were traced in each photograph, excluding any tissue-free spaces. The total amyloid-positive area was measured, and the percentage area of amyloid per whole-tissue section (percent (%) area of amyloid deposition) was calculated. The distribution of amyloid deposits in the kidneys was examined. The significance of differences in the mean percent (%) area of amyloid deposition between the right and left sides and among three long-axis levels (upper, middle and lower) were analyzed by two-way analysis of variance (ANOVA) at a significance level of p <0.05.
  
  
  CONCLUSIONS
  The area of amyloid deposition in these samples was about 7-11%, and the degree of variability among them seemed to be small. It also shows a comparison of amyloid deposition between the right and left sides and between the long axis samples for quadruplicate determinations; no significant differences were evident, and thus the percent (%) area of amyloid deposition throughout the whole kidneys appeared to be uniform in this patient.
authors.affiliation: Division of Clinical Nephrology and Rheumatology, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-Dori, Niigata City 951-8510, Japan. kurodat@med.niigata-u.ac.jp
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kuroda
authors.forename: Naohito
authors.initials: N
authors.lastname: Tanabe
authors.forename: Hiroe
authors.initials: H
authors.lastname: Sato
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nakatsue
authors.forename: Yoko
authors.initials: Y
authors.lastname: Wada
authors.forename: Shuichi
authors.initials: S
authors.lastname: Murakami
authors.forename: Masaaki
authors.initials: M
authors.lastname: Nakano
authors.forename: Ichiei
authors.initials: I
authors.lastname: Narita
mesh_terms: D000682:Amyloid / Q000378:metabolism*; D000686:Amyloidosis / Q000150:complications / Q000000981:diagnostic imaging / Q000378:metabolism*; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000000981:diagnostic imaging / Q000378:metabolism*; D006801:Humans; D007668:Kidney / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D014057:Tomography, X-Ray Computed
chemical_list: D000682:Amyloid