Bone histomorphometry before and after long-term treatment with cinacalcet in dialysis patients with secondary hyperparathyroidism.

ABSTRACT: The multicenter, single-arm BONAFIDE study characterized the skeletal response to cinacalcet in adult dialysis patients with plasma parathyroid hormone (PTH) levels of 300?pg/ml or more, serum calcium of 8.4?mg/dl or more, bone-specific alkaline phosphatase over 20.9?ng/ml and biopsy-proven high-turnover bone disease. Of 110 enrolled patients, 77 underwent a second bone biopsy with quantitative histomorphometry after 6-12 months of cinacalcet treatment. The median PTH decreased from 985?pg/ml at baseline to 480?pg/ml at the end of study (weeks 44-52). Bone formation rate/tissue area decreased from 728 to 336??m(2)/mm(2)/day, osteoblast perimeter/osteoid perimeter decreased from 17.4 to 13.9%, and eroded perimeter/bone perimeter decreased from 12.7 to 8.3%. The number of patients with normal bone histology increased from none at baseline to 20 at 12 months. Two patients had adynamic bone at the end of study with a PTH under 150?pg/ml, and one patient with overt hypophosphatemia at baseline that reoccurred during follow-up developed osteomalacia. Thus, long-term treatment with cinacalcet substantially reduced PTH, diminished the elevated bone formation rate/tissue area, lowered several biochemical markers of high-turnover bone disease toward normal, and generally improved bone histology. Twenty patients had normal bone histology at follow-up, whereas most had mild hyperparathyroidism or mixed uremic osteodystrophy.

SUBMITTER: Behets GJ 

PROVIDER: S-EPMC4382689 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature