Bone and Metabolic Markers in Women With Recurrent Calcium Stones

PURPOSE The target of our work was to study several biochemical parameters in phospho-calcic and bone metabolism in blood and urine and the bone mineral density of women with recurrent calcium nephrolithiasis. MATERIALS AND METHODS We conducted a cross-sectional study with a control group of 85 women divided into 3 groups: group 1 consisted of 25 women without a history of nephrolithiasis, group 2 consisted of 35 women with only one episode of calcium nephrolithiasis, and group 3 consisted of 25 women with a history of recurrent calcium nephrolithiasis. Blood and urine biochemical study was performed, including markers related to lithiasis, and a bone mineral density study was done by use of bone densitometry. RESULTS Patients in group 3 showed statistically significantly elevated calciuria (15.4 mg/dL), fasting calcium/creatinine ratio (0.14), and 24-hour calcium/creatinine ratio (0.21) compared with groups 1 and 2. Moreover, this group of women with recurrent calcium nephrolithiasis had significantly elevated values of beta-crosslaps, a bone resorption marker, compared with groups 1 and 2 (p=0.000) and showed more bone mineral density loss than did these groups. CONCLUSIONS Recurrent calcium nephrolithiasis in women has a significant association with bone mineral density loss and with values of calciuria, both fasting and 24-hour.