Low Bone Turnover State in Primary Biliary Cirrhosis

To determine whether bone loss in patients with chronic cholestatic liver disease is the consequence of a high or low bone turnover state, 30 female patients with biopsy-proven primary biliary cirrhosis underwent iliac crest biopsy following double tetracycline labeling. The mean trabecular bone volume was decreased as a result of trabecular plate thinning in both the premenopausal (p less than 0.02) and postmenopausal (p less than 0.05) patients, compared to age- and sex-matched controls. Indications that osteoblastic function was impaired included a significantly lower mean wall thickness (p less than 0.01) and mean osteoid seam width (p less than 0.05), and this in association with a decreased mineral appositional rate and prolonged mineralization lag time was suggestive of a defect in matrix synthesis. Further evidence of impaired osteoblastic activity was the significantly lower bone formation rate at both tissue (p less than 0.001) and basic multicellular unit levels (p less than 0.05) in the postmenopausal patients. Total resorption surfaces and fasting urinary calcium/creatinine ratios were significantly increased (p less than 0.005 and 0.05, respectively) in the premenopausal patients and mean interstitial bone thickness reduced in both pre- and postmenopausal patients, suggesting that increased resorption may also contribute to bone loss in primary biliary cirrhosis.