Distal Erosions and Nail Psoriasis

Study Overview
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Brief Summary
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Nearly 30% of patients with cutaneous psoriasis (PsO) developed psoriatic arthritis (PsA). Among these patients 20 % will have severe destructive arthritis. The risk of developing PsA is significantly higher in patients with nail involvement (OR = 2.24; 95% CI [1.26-3.98]). The risk is particularly high for the peripheral form of PsA and onycholysis (OR=2.80; 95% CI [1.34-5.85]). Thus the investigators wanted to test the hypothesis that onycholysis, in patients without PsA, is a potential clinical marker of subclinical distal enthesopathy and, by extension, of bone micro-structural alterations. Patients and Methods The investigators will recruit 4 groups of subjects: Patients with peripheral PsA, Patients with psoriatic nail onycholysis, Patients with PsO only Healthy match control subjects. The investigators will assess the presence of enthesopathy by ultrasonography and bone structural damages (by HR-pQCT) in all subjects at baseline and 4 years.

Official Title
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Distal Phalangeal Bone Involvement Observed by High Resolution Peripheral Quantitative Computed Tomography (HR-pQCT) in Patients With Nail Psoriasis

Conditions
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Psoriatic Arthritis

Intervention / Treatment
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* Radiation: HR-pQCT High resolution peripheral quantitative CT-scan


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: adults over 18 years and until 65 years both gender covered by the French National Insurance subjects entering one of the 4 groups. Exclusion Criteria: Treatment by biological agents are an exclusion criteria for PsO, onycholysis and control patients. Pregnant women

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with peripheral PsA<br> | Radiation: HR-pQCT High resolution peripheral quantitative CT-scan<br>* HR-pQCT is a powerful device providing low dose irradiation already used in bone field. It is a high resolution tool (voxel size=82µm) that the investigators adapted to look after the distal joint involved by onycholysis. An anteroposterior scout view is used to define the region of interest (ROI), which spanned from the top of the distal phalange to the distal part of the intermediate phalange in order to contain the distal joint of the target finger. Images are then analysed for erosions, osteophytes and volumetric bone mineral density.<br>|
| Patients with psoriatic nail onycholysis<br> | Radiation: HR-pQCT High resolution peripheral quantitative CT-scan<br>* HR-pQCT is a powerful device providing low dose irradiation already used in bone field. It is a high resolution tool (voxel size=82µm) that the investigators adapted to look after the distal joint involved by onycholysis. An anteroposterior scout view is used to define the region of interest (ROI), which spanned from the top of the distal phalange to the distal part of the intermediate phalange in order to contain the distal joint of the target finger. Images are then analysed for erosions, osteophytes and volumetric bone mineral density.<br>|
| Patients with PsO only<br> | Radiation: HR-pQCT High resolution peripheral quantitative CT-scan<br>* HR-pQCT is a powerful device providing low dose irradiation already used in bone field. It is a high resolution tool (voxel size=82µm) that the investigators adapted to look after the distal joint involved by onycholysis. An anteroposterior scout view is used to define the region of interest (ROI), which spanned from the top of the distal phalange to the distal part of the intermediate phalange in order to contain the distal joint of the target finger. Images are then analysed for erosions, osteophytes and volumetric bone mineral density.<br>|
| Healthy match control subjects<br> | Radiation: HR-pQCT High resolution peripheral quantitative CT-scan<br>* HR-pQCT is a powerful device providing low dose irradiation already used in bone field. It is a high resolution tool (voxel size=82µm) that the investigators adapted to look after the distal joint involved by onycholysis. An anteroposterior scout view is used to define the region of interest (ROI), which spanned from the top of the distal phalange to the distal part of the intermediate phalange in order to contain the distal joint of the target finger. Images are then analysed for erosions, osteophytes and volumetric bone mineral density.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| distal phalangeal bone erosion of the 2 index fingers of the hand | assessment by HR-pQCT | at baseline and after 4 years of follow-up | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| enthesopathy of the 2 index fingers of the hand | assessment by ultrasonography | at baseline and after 4 years of follow-up | 
| Rheumatoid factors |  | Biomarkers are assessed at baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Erosions, Onycholysis, HR-pQCT, Psoriatic arthritis