COMPARISON BETWEEN SERUM LEVELS OF BONE ALKALINE-PHOSPHATASE AND THE CARBOXY-TERMINAL PROPEPTIDE OF TYPE-I PROCOLLAGEN AS MARKERS OF BONE-FORMATION IN PATIENTS FOLLOWING RENAL-TRANSPLANTATION

The serum concentrations of the carboxy-terminal propeptide of type I procollagen (PICP) were monitored in 52 serum samples from 13 patients receiving renal transplants and the values compared with bone alkalin e phosphatase (BAP) concentrations and intact parathyrin levels, There was a significant correlation between BAP and PICP values in all 52 s erum samples examined (r = +0.770; P < 0.0001). Before transplantation BAP (P < 0.0001), but not PICP (P > 0.1), was correlated with intact parathyrin levels. BAP concentrations increased from 7.3 +/- 1.2 mu g/ l (median +/- S.E.M.) before transplantation to 13.3 +/- 1.2 mu g/l 3 months after transplantation (P < 0.01). There was a concomitant rise in PICP levels from 95 +/- 19 mu g/l to 166 +/- 27 mu g/l (P < 0.05). No correlation was found between BAP or PICP levels on the one hand an d intact parathyrin concentrations on the other at any time following renal transplantation (P > 0.5). In conclusion, PICP may be a useful p arameter for monitoring bone formation following renal transplantation .