The role of prolidase activity in the diagnosis of uremic bone disease.

The derangements in bone metabolism in patients with chronic renal failure (CRF) are summarized as uremic bone disease (UBD). In this study, we planned to determine the serum prolidase to compare it with the other biochemical markers. This study was performed on 44 patients (19 females, 25 males, mean age = 56.8 +/- 15.6 years) with endstage renal disease (ESRD). The patients were divided into three groups according to serum bone alkaline phosphatase (bAP) levels. The patients whose bAP was > or =77 U/L were accepted as having high-turnover UBD (n=18), the patients whose bAP was < or =50 U/L were accepted as having low-turnover UBD (n=14), and the patients whose bAP levels were between these two values were accepted as having bone disease with normal turnover (n=12). The serum prolidase levels did not increase in patients with ESRD. There were no significant differences between the serum prolidase levels of patients according to types of the UBD (p > 0.05). Kidney is the most prolidase-rich tissue of the human body. The serum prolidase activity is low in all patients with ESRD, irrespective of the type of UBD. Therefore, we concluded that prolidase had no value in the diagnosis of UBD.