Study of the Correlation Between UltraSonography and Dual-Energy Computed Tomography Assessment of Urate Deposit

Study Overview
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Brief Summary
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The objective of this research is to evaluate the correlation between DECT and US explorations performed in a routine clinical setting for the measurement of change in tophus size in gout patients after 24 months of treatment.

Official Title
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Study of the Correlation Between UltraSonography and Dual-Energy Computed Tomography Assessment of Urate Deposit in Urate Lowering Therapy Initiators

Conditions
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Gout

Intervention / Treatment
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* Procedure: ultrasonography
* Procedure: DECT


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: diagnosis of gout based on the ACR/EULAR 2015 criteria uricemia ≥6 mg/dL warranted introduction of urate-lowering therapy according to the ACR 2012 or EULAR 2016 criteria signature of the informed consent social insurance affiliation Exclusion Criteria: pregnancy or breastfeeding patient under legal guardianship

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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 |
| --- | --- |
| Experimental: UltraSonography and DECT<br>UltraSonography and DECT will be used in patient monitoring after 6, 12 and 24 months of treatment in order to evaluate the correlation between the 2 explorations for the measurement in tophus volume change. Those are interventions that are not part of the standard care of the patients. | Procedure: ultrasonography<br>* The tophus volume will be assess using ultrasonography.<br>Procedure: DECT<br>* The tophus volume will be assess using dual-energy computed tomography (DECT).<br>* Other names: dual-energy computed tomography;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between US and DECT measurement of change in tophus volume | Spearman rank correlation between the change in tophus volume after 24 months of treatment measured by ultrasonography or by DECT. | after 24 months of treatment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between US and DECT measurement of change in tophus volume | Spearman rank correlation between the change in tophus volume after 6, 12 and 24 months of treatment measured by ultrasonography or by DECT. | after 6 months, 12 months and 24 months of treatment | 
| Change of DECT urate score | Change from baseline after 6, 12 and 24 months of treatment in DECT urate score | after 6 months, 12 months and 24 months of treatment | 
| Link between the change of DECT urate score and the persistence of the double contour sign | During ultrasonography, a double contour of the articulation can be visible. This outcome will compare the change in the DECT urate score between the patients for who the double contour stay visible and those for who it disapear. This outcome register if this double contour stay visible. | after 6 months, 12 months and 24 months of treatment | 
| Correlation between the change of DECT urate score and the change in serum uric acid levels | The Spearman correlation between the change from baseline of the DECT urate score and the serum uric acid levels will be computed for each time point. | after 6 months, 12 months and 24 months of treatment | 
| Correlation between the change of DECT urate score and the number of gout attacks | The Spearman correlation between the change from baseline of the DECT urate score and the number of gout attack will be computed. | after 6 months, 12 months and 24 months of treatment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Dual-Energy Computed Tomography, UltraSonography, Gout, Urate deposition