The authors examined 49 patients (n=49) with primary and secndary osteoporosis incl. 37 women aged 41-58 years and 12 men aged 38-56 years. In all they assessed the 24-hour calciuria index (Ca/creatinine), the aminoterminal N-telopetide of collagen I of the organic matrix (NTx24) and the bone mineral density (BMD) in the first three lumbar vertebrae using quantitative computed tomography (QC).Objective: To find an answer to the questions:1. Is the calciuria index in the 24-hour diuresis a parameter which provides information on osteresorption? 2. Is there a signifi- cant negative correlation between values NTx24 and BMD? 3. Is NTx a sensitive parameter of osteoresorption in men and women with primary or secondary osteoporosis? Statistical analysis: Linear regression analysis. Results: Correlation coefficients for the correlated groups NTx24 - Ca/creatinine (r= 0.023, p>0.05) and NTx24 - BMD (r= - 0.238, p>0.05) were not statistically signifi- cant. Statistical significance was recorded in the correlation coefficient for pathologically eleva- ted values of NTx24(zNTx24), correlated with BMD (r = -0.3115, p<0.048). Conclusion: 1. The calciuria index in the 24-hour diuresis does not provide information on osteo- resorption. 2. Between pathologically elevated values of NTx24 and BMD in L1-L3 is a statistically significant negative correlation. 3. NTx is a sensitive parameter of osteresorptioon in men and women with primary and secondary osteoporosis, it reflects the influence of the bone turnover on the density of the bone mineral.

        Key words: N-telopetide - Calciuria - Bone mineral density - Bone metabolism - Osteoporosis.