C telopeptides of type I collagen inpostmenopausal women: an experience in a Tunisian clinical laboratory

The purpose of study was to evaluate the interest of C-telopeptides of type I collagen [CTX] in the diagnosis of osteoporosis in postmenopausal women and to define its cut-off value. A transverse descriptive study enrolled postmenopausal women: 139 osteoporotic [G1] and 39 non osteoporotic [G2]. The 2 groups were defined by bone density measurement. The followmg markers were measured: serum alkaline phosphatase [ALP] bone alkaline phosphatase [bone ALP], serum C-terminal telopeptide of type I collagen [CTX]. Statistical analyses were performed using SPSS 10, 5. The corresponding estimation of sensitivity and specificity of CTX have been presented as receiver Operating Curve [ROC]. There was no difference in the measurement of ALP and bone ALP in the 2 groups but CTX was statistically higher in G1 compared to G2 [p<0.001]. The percentage of osteoporotic women [G1] with CTX values>0.500 ng/ml was higher than that of non osteoporotic women [G2]. We have established a ROC curve to find the cut-off value of CTX that enables the distinction between osteoporotic women with high level of bone remodelling, and non osteoporotic women. The cut-off value of CTX 0.55 pg/mi was the best; it associated best sensitivity and specificity. The total increase and significance for CTX was greater in the group of osteoporotic women and appeared therefore to be a good bone turnover marker in the diagnosis of osteoporosis in comparison with ALP and bone ALP. The cut-off value of CTX 0.55 pg/mi may improve the sensitivity and specificity of prediction of future fractures

[Hypovitaminosis D in Tunisian osteoporotic post menopausal women and its relationship with bone fracture]

The purpose of this study is to evaluate the frequency of hypovitaminosis D in Tunisian osteoporotic women and to search an eventual association between vitamin D status and the fracture risk. A transverse descriptive study enrolled 134 osteoporotic menopausal women aged 50 years or more. We measured calcium, phosphorus, albumin, alkaline phosphatase, creatinine and 25 hydroxyvitamin D [25 [OH] vit D]. Bone mineral density [BMD] was measured for all and osteoporotic women were defined for a T-score of -2,5 or less in the spine, hip or femoral neck .Two groups were defined: G1 with fracture and G2 without fracture .We used SPSS 10.5, X2 tests and a statistical significance level of p< 0,05. Women in G1 [n= 102] were more aged than those in G2 [n= 32] and their menopause was more ancient. Hypovitaminosis D was found in 45,2% of all women, respectively in 50,98% of G1 and 25% of G2. The mean level of vitamin D was more important in G2 [27,5+ 15,1 vs 21,3 + 12,8 ng/ml; p=0,002]. BMD in femoral and lumbar were statistically lower when fractures are present [p< 0,001]. Our study shows that women with hypovitaminosis D [vit D < 20 ng/ml] are prone to osteoporotic fractures. All fracture in community in menopausal women, should be assessed with BMD and screening for 25 [OH] vit D. Increasing life expectancy in our country suggests that this public health problem will grow in the years to come, pointing out the importance of better management of osteoporosis and hypovitaminosis D to prevent fractures

[Effects of risedronate on bone turnover markers in osteoporotic postmenopausal women: comparison of two protocols of treatment]

Bisphosphonates are powerful agents able to prevent bone loss. The objective of the study was to evaluate the efficacy and tolerability of risedronate once a week [35 mg] compared with risedronate 5 mg once daily in women with osteoporosis. A randomized, double-blind, active controlled study enrolled 102 postmenopausal women aged 66.5+7.5 years with osteoporotic fractures. All women received risedronate during 6 months. Group 1 [G1, n=51] received risedronate 5 mg once daily and group 2 [G2, n=51] received 35 mg once a week. Serum alkaline phosphatase [ALP], bone alkaline phosphatase [bone ALP], serum C-terminal telopeptide of type I collagen [CTX] were measured at baseline, 3 months and 6 months after treatment in the two groups. We noted no significant difference in markers between women of the 2 groups. After 3 months, bone ALP and CTX decreased [respectively -22.1% and -47.6%] in the 2 groups with no significant difference between them. After 6 months study, bone ALP and CTX decreased respectively by -46.5% and -62.9% with no statistically significant difference between study groups for bone markers. Our study found that treatment with once weekly risedronate 35 mg is able to decrease CTX and bone ALP compared with risedronate 5 mg once daily, in postmenopausal women with osteoporotic fractures. We didn't find adverse events with the 35 mg once a-week dose group compared to the once-daily dose group. Based on these results, the effects of risedronate 35 mg once a week are similar in efficacy to daily dosing and may lead less adverse events than once-a month dose. This therapeutic protocol may provide an alternative for patients who prefer once a week oral dosing

Effects of risedronate on bone turnover markers in osteoporotic postmenopausal women: comparison of two protocols of treatment

Bisphosphonates are powerful agents able to prevent bone loss. The objective of the study was to evaluate the efficacy and tolerability of risedronate once a week [35 mg]-compared with risedronate 5 mg once daily in women with osteoporosis. A randomized, double-blind, active-controlled study enrolled 102 postmenopausal women aged 66.5_7.5 years with osteoporotic fractures. All women received risedronate during 6 months. Group 1 [G1, n=5 1] received risedronate 5 mg once daily and group 2 [G2, n=51] received 35 mg once a week. Serum alkaline phosphatase [ALP], bone alkaline phosphatase [bone ALP], serum C-terminal telopeptide of type I collagen [CTX] were measured at baseline, 3 months and 6 months after treatment in the two groups. We noted no significant difference in markers between women of the 2 groups. After 3 months, bone ALP and CTX decreased [respectively-22.1%and-47.6%] in the 2 groups with no significant difference between them. After 6 months study, bone ALP and CTX decreased respectively by-46.5%and-62.9%with no statistically significant difference between study groups for bone markers. Our study found that treatment with once weekly risedronate 35 mg is able to decrease CTX and bone ALP compared with risedronate 5 mg once daily, in postmenopausal women with osteoporotic fractures. We didn't find adverse events with the 35 mg once-a-week dose group compared to the once-daily dose group. Based on these results, the effects of risedronate 35 mg once a week are similar in efficacy to daily dosing and may lead less adverse events than once-a-month dose. This therapeutic protocol may provide an alternative for patients who prefer once-a-week oral dosing

[Soluble transferrin receptor in the biologial diagnosis of iron deficiency. about 24 cases]

In inflammatory diseases, classical parameters of iron status [serum iron, serum ferritin. total iron-binding capacity of transferrin and transferrin saturation] are not very reliable. The purpose of this study is to investigate soluble transferrin receptor, its index and classical parameters of iron status [serum iron serum ferritin, total iron-binding capacity of transferrin and transferrin saturation] during iron-deficiency anemia and combined iron deficiency and inflammatory anemia. Out study concerned 24 patients: 18 patients with iron-deficiency anemia and 6 patients with combined iron-deficiency and inflammatory anemia, 55 healthy subjects were included as controls. Both groups underwent classical parameters of iron status [serum iron, serum ferritin, total iron-binding capacity of transferrin and transferrin saturation] and measurement of soluble transferrin receptor with its index. In iron-deficiency anemia, total iron-binding capacity of transferrin, soluble transferrin receptor and its index were enhanced, whereas serum iron, ferritinemia and transferrin saturation were low compared so controls. Compared to patients with iron-deficiency anemia, those with combined iron-deficiency and inflammatory anemia showed higher levels of serum iron and ferritinemia. In contrast, soluble transferrin receptor and its index did not vary significantly between both groups. Our findings show the interest of soluble transferrin receptor and its index in the detection of iron deficiency during anemia of inflammatory states

[Interest of bone alkaline phosphatase in hemodialysis patients]

The renal osteodystrophy represent a major complication in haemodialysis. Of this study is to evaluate the value of plasma bone-alkaline phosphatase [bAP] in the diagnosis of the type of renal osteodystrophy among hemodialysis patients and to seek a possible correlation between the bAP, total alkaline phosphatases [tAP] and the intact parathormone [iPTH]. We studied 67 chronic hemodialysis patients. Plasma bAP was determined by immunoenzymatic technic. iPTH [1-84] was measured by electrochimiluminescence. We found that bAP levels were normal 10-20 ng/ml] in 17 patients low [< 10 ng/ml] in 4 and high [> 20 ng/ml] in the 46 other patients. There is a good positive is e correlation between the plasmatic rate of bAP and the following parameters: the period of dialysis [R = 0.316, p = 0,009]. plasmatic rate of tAP [r = 0.781. p < 10[-3]] and the rate of iPTH [r = 0,650]. p < 10[-3]]. There is a good positive correlation between the plasmatic rate of bAP and the rates of the tAP and of iPTH, the correlation between bAP and the ipTh being more significant. A rate of bAP higher than 20 ng/ml had a sensitivity of 93,5% specificity of 63,3% in favour of a rate of iPTH > 400 pg/ml and consequently of the biological diagnosis of hyperparathyroidism. In addition, 4 patients have a bAP < 10 ng/ml with iPTH < 150 pg/ml evoking an adynamic osteopathy. plasma bAP provides useful information about bone remodelling in hemodialysis patients