Systematic Study of Parameters of Chronic Kidney Disease Mineral and Bone Disorder (CKD-MBD)

Study Overview
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Brief Summary
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Bone and mineral disease is a key problem in patients with kidney disease. The available clinical parameters are non-specific, unproven for the assessment of the bone metabolism and do not reflect the complexity and diversity of the underlying bone pathology. The aim of this study is to use bone histology, novel bone markers and bone imaging results to establish a reliable decision model (diagnostic tool) that can be used to guide the individual therapy.

Detailed Description
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Bone and mineral disease is a key problem in patients with kidney disease. The available clinical parameters are non-specific, unproven for the assessment of the bone metabolism and do not reflect the complexity and diversity of the underlying bone pathology. In this study bone histology parameters including results of tetracycline labeling will be compared to non-invasive parameters of bone metabolism (e.g. sclerostin, calciprotein particles) and bone structure obtained by imaging (e.g. bone density). The aim of the study is to establish a reliable decision model (diagnostic tool) with these non-invasive parameters that can be used to guide the individual therapy. The decision model will be based on single calculations of the area under the curve for each parameter, including determination of the optimal cutpoint, sensitivity and specificity. These results will be integrated in a multivariate logistic regression analysis. The resulting model will enable to calculate the individual probability of the underlying bone diagnosis as a single value (without a specific dimension).

Official Title
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Systematic Study of Parameters of Chronic Kidney Disease Mineral and Bone Disorder (CKD-MBD)

Conditions
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Renal Osteodystrophy

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with kidney disease who have an indication for a bone biopsy, based on clinical, laboratory and radiologic findings Exclusion Criteria: known malignant bone or bone marrow disease

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Accuracy of a diagnostic model (derived from the non-invasive radiologic and blood parameters of the bone) in relation to the 'gold standard' bone biopsy result | After determining the AUC, sensitivity, specificity and optimal cutpoint for each parameter, a logistic regression model is created which gives the probability of the underlying bone diagnosis as a single probability value. In this cross-sectional studies each patient gets a one-time assessment of radiologic and blood parameters of bone metabolism obtained within one week. Accuracy is described by the performance measures sensitivity, specificity, area under the curve, negative and positive predictive values. | cross-sectional study, one week | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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bone biopsy; bone density