Quantitative Computed Tomodensitometry in Patients With Cystic Fibrosis

Study Overview
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Brief Summary
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The purpose of this study is to conduct a comparative study for the study of bone mineralization evaluated with Quantitative computed tomodensitometry (QCT) compared to the reference technique, Dual-emission X-ray absorptiometry (DXA).

Detailed Description
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Patients with cystic fibrosis can have a deficit in bone mineralization. This is particularly well described in adults. However, in the pediatric population the results are more heterogeneous. The evaluation is hindered by difficulties in standardization of DXA interpretation. This measurement depends from the mass and size of the bone as well as the mass of soft tissue covering the bone area. These two characteristics, intrinsic to the measurement, pose a significant problem of interpretations in children because a change in bone density may reflect both a change in bone mineral content or changes related to growth, for example, the increase in bone size or volume of soft tissue covering the bone of interest. Quantitative computed tomography (QCT) provides a direct measure of bone mineralization densitometry volume. It quantifies bone mineral content in relation to the volume of the bone, in reference to an external phantom. This method therefore overcomes the size size. This technique can be considered without an additional radiation exposure to patients during a lung CT because it is usual that lumbar vertebrae are included in the measurement window because of pulmonary hyperinflation. This exam would be ideal for patients with Cystic fibrosis. All patients have these two evaluations during their routine management. This study compare study on the bone mineralization evaluated by (QCT) compared to the reference technique by (DXA) for the patient affected by cystic fibrosis for each patient.

Official Title
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Evaluation of the Bone Mineralization by Quantitative Computed Tomodensitometry in Patients With Cystic Fibrosis : Validation Study

Conditions
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Cystic Fibrosis

Intervention / Treatment
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* Other: QCT
* Other: DXA


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients affected by cystic fibrosis Aged over 5 years Patients whose clinical condition warrants an indication of chest CT in relation to the criteria of the french consensus conference on Cystic fibrosis in May 2002 (Palace of the Luxembourg). Patients whose clinical condition warrants an indication of DXA examination in accordance with French recommendations (Consensus of the Working Group bone mineralization and cystic fibrosis In children, the examination is recommended for ages 8 every 2 years if the Z-score is greater than - 1, every year if the Z-score is less than - 1.. In adults, the exam is recommended every 5 years if the T-score is greater than> - 1, every 2 years if it is between -1 and - 2; annually if less than - 2.) Patient does not exhibit a phase of bronchial exacerbation Collection of non-opposition of the patient Patient affiliated to social security Exclusion Criteria: Patient transplanted Patient with an infective exacerbation phase

Ages Eligible for Study
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Minimum Age: 5 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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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: QCT and DXA<br>All the patients will have both QCT and DXA | Other: QCT<br> <br> * Other names: Quantitative Computed Tomodensitometry;Other: DXA<br> <br> * Other names: Dual-emission X-ray;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evaluation of the mineralization with DXA(Dual-energy X-ray absorptiometry) as a Zscore of Bone mineral density and the Zscore of QCT (Quantitative computed tomography) | Evaluation of the mineralization with DXA(Dual-energy X-ray absorptiometry) as a Zscore of Bone mineral density(reference population: same sex, same bone age) and the Zscore of QCT (Quantitative computed tomography) (reference population: same sex, same age) | 1 day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evaluation of the prevalence of osteopenia in children and adult affected by cystic fibrosis. |  | 1 day | 
| Correlation of bone mineralization with nutritional status (BMI) |  | 1 day | 
| Correlation of bone mineralization with respiratory status (FEV % predicted) |  | 1 day | 
| Correlation of bone mineralization with Vitamine D (25(OH)vitD) |  | 1 day | 
| Correlation of bone mineralization with the amount of total inhaled and oral corticosteroids administered (total number of days of steroids according to diiferent modalities: inhaled, oral IV) |  | 1 day | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cystic fibrosis-DXA-QCT-Osteopenia- Osteoporosis