title: Early changes of bone histology and circulating markers of bone turnover after parathyroidectomy in hemodialysis patients with severe hyperparathyroidism.
abstract: OBJECTIVE
  There have so far been no reports on the changes in bone histology in the early period after parathyroidectomy and autografting (PTX-AG). We investigated the effects of PTX-AG on bone histology during the initial 12 weeks after undergoing these surgical procedures.
  
  
  METHODS
  We performed bone histomorphometry 3 times (before as well as 4 and 12 weeks after PTX-AG) in 6 patients and 2 times (before and 4 weeks after PTX-AG) in 3 hemodialysis patients. In addition, the circulating parameters of bone metabolism were also assessed before and after PTX-AG in all 9 patients. The changes in the histomorphometric (static) parameters between pre-surgery and 4 weeks after surgery and those between 4 weeks and 12 weeks after surgery were assessed by the t-test while changes in the circulating parameters of bone metabolism were analyzed by Friedman's test.
  
  
  RESULTS
  Bone formation parameters including carboxy terminal propeptide of human type I procollagen (PICP), alkaline phosphatase (ALP) and intact osteocalcin (i-OC) were all extremely high before surgery. These parameters initially increased after PTX-AG and thereafter gradually declined. In contrast, the circulating bone resorption parameters including tartrate-resistant acid phosphatase (TRAP) and deoxypyridinoline (Dpyr) were also extremely high at baseline but markedly declined after operation. Osteoid-related parameters including osteoid volume (OV/BV), osteoid surface (OS/BS), and osteoid thickness (O.Th) all initially increased at 4 weeks after PTX-AG. In contrast, osteoblast surface (Ob.S/BS), osteoclast surface (Oc.S/BS), eroded surface (ES/BS), and fibrosis volume (Fb.V/TV) all decreased at 4 weeks after surgery, while Ob.S/BS decreased further at 12 weeks in cases 1-6. Although bone mineralization was ongoing at 4 weeks after surgery, both the mineral apposition rate (MAR) and bone formation rate (BFR) remained below the mean for normal individuals.
  
  
  CONCLUSIONS
  The circulating bone formation parameters and osteoid-related parameters showed an initial increase after PTX-AG. The concomitant decline in the circulating bone resorption parameters reflected the reduction in bone resorption. BFR decreased, but bone mineralization did not stop after PTX-AG.
authors.affiliation: Department of Nephrology, Towa Hospital, Japan. a-and-y@rj8.so-net.ne.jp
authors.forename: A
authors.initials: A
authors.lastname: Yajima
authors.forename: K
authors.initials: K
authors.lastname: Tanaka
authors.forename: Y
authors.initials: Y
authors.lastname: Tominaga
authors.forename: Y
authors.initials: Y
authors.lastname: Ogawa
authors.forename: T
authors.initials: T
authors.lastname: Tanizawa
authors.forename: T
authors.initials: T
authors.lastname: Inou
authors.forename: O
authors.initials: O
authors.lastname: Otsubo
authors.forename: K
authors.initials: K
authors.lastname: Otsubo
mesh_terms: D000135:Acid Phosphatase / Q000097:blood; D000368:Aged; D000469:Alkaline Phosphatase / Q000097:blood; D000596:Amino Acids / Q000097:blood; D001862:Bone Resorption; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood; D010010:Osteoclasts / Q000502:physiology; D010012:Osteogenesis; D010280:Parathyroid Glands / Q000601:surgery / Q000637:transplantation; D016105:Parathyroidectomy; D011347:Procollagen / Q000097:blood; D006435:Renal Dialysis; D014182:Transplantation, Autologous
chemical_list: D000596:Amino Acids; D011347:Procollagen; D015675:Osteocalcin; C036020:deoxypyridinoline; D000469:Alkaline Phosphatase; D000135:Acid Phosphatase