Plasma pyridinium crosslinks as markers of renal osteodystrophy in patients on maintenance hemodialysis

We measured plasma concentrations of pyridinoline (Pyr) and deoxypyridinoline (Dpyr), markers of bone resorption, by high-performance liquid chromatography in 34 patients on maintenance hemodialysis. As controls, 13 adults with normal renal function were employed. Pyr was undetectable in 7 of the controls (the detection limit of both Pyr and Dpyr: 3pmol/ml). The highest Pyr value in the controls was 7pmol/ml. Dpyr was undetectable in all controls. In all hemodialytic patients, both Pyr and Dpyr values were several to tens times higher than those in controls. There was a very close correlation between Pyr and Dpyr (r=0.955, p