Epidemiological Analysis for Hereditary Angioedema Disease

Study Overview
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Brief Summary
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An international, multicenter, epidemiological, observational study investigating the prevalence of Hereditary Angioedema (HAE) disease among participants with recurrent episodes of abdominal pain of no obvious etiology.

Detailed Description
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Hereditary Angioedema (HAE) is a rare autosomal dominant disorder characterized most commonly by deficient (type 1) or nonfunctional (type 2) C1 inhibitor protein (encoded by SERPING1 gene). The disorder is associated with episodes of angioedema of the face, larynx, lips, abdomen, and extremities. The angioedema is caused by the activation of the kallikrein-kinin system that leads to the release of vasoactive peptides, followed by edema, which in severe cases can be life threatening. Gastrointestinal involvement occurs in 93% of patients with HAE and may be the only manifestation of the disease. However, individuals with gastrointestinal symptoms are rarely considered for HAE and the disease can be misdiagnosed for several years. EHA study focuses on the gastrointestinal complications of HAE as a potential area of misdiagnosis leading to surgical morbidity. Aim of the study is to investigate the prevalence of HAE among participants experiencing recurrent abdominal pain attacks with no clear etiology. The HAE-positive samples in the study will be further analyzed biochemically to identify disease-specific biomarker that may support the development of new diagnostic tools for HAE disease.

Official Title
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Epidemiological Analysis for Hereditary Angioedema Disease: An International, Multicenter, Epidemiological Protocol

Conditions
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Abdominal Pain, Functional Abdominal Pain

Participation Criteria
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Eligibility Criteria
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INCLUSION CRITERIA Informed consent will be obtained from the participant or the parent or legal guardian Participants with previous episodes of abdominal pain of no obvious etiology Participants aged between 2 to 60 years old EXCLUSION CRITERIA Previous diagnosis of HAE Inability to provide informed consent The etiology of abdominal pain attacks is determined Participants that are younger than 2 years old or older than 60 years old Previous enrolled in the study

Ages Eligible for Study
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Minimum Age: 2 Years
Maximum Age: 60 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Participants with abdominal pain attacks<br>Participants experiencing recurrent abdominal pain attacks without a clear etiolgy aged between 2-60 years | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Epidemiological analysis of prevalence of the HAE in participants with previous episodes of abdominal pain of no obvious etiology. | Dry Blood Spot (DBS)-based biochemical measurements of C4 complement and the protease C1 inhibitor levels will be analyzed via liquid chromatography multiple reaction. The pathological biochemical results will be genetically validated via combination of the Next-Generation Sequencing (the mutation will be confirmed by Sanger sequencing) and Multiplex ligation-dependent probe amplification of SERPING1. | 4 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Establishment of a biomarker in HAE-positive cohort | HAE-positive samples will be analyzed for the identification of potential biomarkers (based on MS/MS-Tandem spectroscopy) and compared with the merged control samples in order establish a HAE specific biomarker. | 4 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hereditary Angioedema, DBS-based biochemical and genetic assay for HAE type I/II, Biomarker