Infliximab Blood Test in Crohn's Disease

Study Overview
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Brief Summary
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Ano-perineal lesions are the first signs of Crohn's disease in 1/3 to 1/2 of cases. They are most often associated with a poor prognosis of the disease and their management is complex and difficult because of the dilapidated and recurrent nature of lesions with significant repercussions on continence and quality of life. The treatment of these lesions is most often medical and surgical, consisting of drainage of the suppurative lesions and/or the use of biotherapy +/- combined with an immunosuppressant.

Detailed Description
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Pharmacological dosages of biotherapies show a significant correlation between the highest rates and the achievement of clinical and endoscopic remission. Therapeutic monitoring by dosing the residual levels of these biotherapies and specific antibodies, particularly in the event of loss of response in order to adapt the treatment, has become common for luminal damage. Among these biotherapies, infliximab is the first-line treatment, particularly for ano-perineal disease. Effective therapeutic levels are known for luminal damage and must be between 3 and 7 mcg/ml but these levels have not yet been determined for ano-perineal damage. There are only two recently published studies available that suggest levels probably significantly higher than those required for luminal damage ≥ 10 mcg/l

Official Title
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Infliximab Blood Test in Crohn's Disease

Conditions
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Crohn Disease

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All patients followed for Chron's diseases within Groupe Hospitalier Paris Saint-Joseph (GHPSJ) and treated with Infliximab for at least 6 months. Exclusion Criteria: All patients with therapeutic compliance problems

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 |
| --- | --- | --- |
| Identify doses and residual levels of infliximab in patients affected by ano-perineal Crohn's disease in remission | doses and residual levels of infliximab in remission patients will be collected to determine minimum, maximum and average values. | Time of inclusion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Compare doses and residual rates of infliximab in patients affected by Crohn's disease in remission with luminal impairment alone versus ano-perineal +/- luminal | Doses and infliximab's residual levels will be collected from patients affected by Crohn's disease in remission with luminal alone and from patients in remission with ano-perineal +/- luminal for comparison | Time of inclusion | 
| Evaluate the proportion of patients in luminal remission with active ano-perineal disease | Calculation of patient's proportion with active ano-perineal disease on total of all patients in luminal remission. | Time of inclusion | 
| Compare residual doses and infliximab levels in patients with ano-perineal disease in remission versus active | Infliximab doses, infliximab residual levels will be collected from patients affected by Crohn's disease with ano-perineal involvement to compare remission patients and patients with active disease. | Time of inclusion | 
| Anti-infliximab antibodies presence (yes/no) in patients with ano-perineal disease in remission versus active | Anti-infliximab antibodies will be collected from patients affected by Crohn's disease with ano-perineal involvement to compare remission patients and patients with active disease. | Time of inclusion |