Tartrate-resistant acid phosphatase and osteocalcin in patients with osteoporosis and osteopenia

Abstract

A way to estimate the activity of the osteoclasts is to measure the catalytic activity of the tartrate-resistant acid phosphatase (TRAP), as the bone cells secrete it during the resorption. Osteocalcin (OC) is a non-collagen peptide involved in the bone mineralization process. It is used in early diagnosis of the primary osteoporosis. The aim of our work was to determine if there was a difference in both the catalytic activity of the TRAP and the serum concentration of OC in patients affected by osteoporosis and osteopenia. The bone mineral density T-score (BMD) of the first group of patients (n=60) was not higher than -2.3, defined by the WHO as osteoporosis. The T-score of the second group (n=60) was found to be between -0.4 and -1.7, defined by the WHO as osteopenia. The catalytic activity of TRAP was determined by the kinetic method proposed by the BIOMERIEUX Company (Germany), using a Mira Cobas plus analyzer (Germany). The BMD was determined by an ultrasound technique. The ROCHE ECL technique and the Elecsys 2010 analyzer (Germany) were used to measure the OC concentration. The results show a significant increase in the catalytic activity of TRAP in the osteoporosis patients sera when compared with the group with osteopenia (p<0.001). Statistically significant difference was found between the groups in the case of OC (p<0.01). We conclude that the TRAP catalytic activity in serum, as well as OC concentration measurement, together with other biochemical markers of bone turnover, can be useful in the diagnosis of osteoporosis.