Research of Biomarkers Associated With the Diagnosis and Severity of Bradykinin Angioedema

Research of Biomarkers Associated With the Diagnosis and Severity of Bradykinin Angioedema

The unpredictable nature of the attacks is one of the essential characteristics of bradykinin angioedema. The two main difficulties for physicians managing a patient with bradykinin angioedema are to make the diagnosis and anticipate the severity.

Biomarkers can be used to diagnose, guide treatment, or predict the severity of a disease. However, the identification of biomarkers is currently difficult in bradykinin both for diagnosis and prognosis. While measurement of C4 and C1 inhibitor (quantitative and functional assays) allows the diagnosis of bradykinin angioedema due to C1 inhibitor deficiency, whether genetic or acquired, many patients with normal C1 inhibitor bradykinin angioedema, either hereditary or acquired, are still difficult to diagnose. For patients with hereditary angioedema with C1-inhibitor deficiency, there is no biomarker currently available to predict the severity. Any biomarker that could improve the diagnosis on the one hand, and improve the prediction of the frequency and severity of the response to treatment on the other hand, would obviously be extremely useful. The aim of our study is to assess the existence possible biomarkers for diagnosis and prognosis of bradykinin angioedema.

Inclusion Criteria:

• Group 1 : Patients with bradykinin angioedema
• Patient with biologically proven hereditary angioedema with C1 inhibitor deficiency,
• Or a patient with bradykinin angioedema related to a plasminogen or factor XII mutation,
• Or patients with bradykinin angioedema related to ACE inhibitors or ARB2,
• Or patient with acquired bradykinin angioedema due to C1 inhibitor deficiency,
• Age > or = 18 years with the capacity to understand the requirements of the study and to give a non-opposition
• Having a blood collection scheduled as part of routine care
• Being insured by social security

Group 2 : Patients with histamine-mediated angioedema

• Patient with idiopathic histamine angioedema as determined by the referring physician
• Age > or = 18 years with the capacity to understand the requirements of the study and to give a non-opposition
• Having a blood collection scheduled as part of routine care
• Being insured by social security

Exclusion Criteria:

• Minors or protected adults,
• Pregnant or breastfeeding woman,
• Person deprived of liberty,
• Person in an emergency situation,
• Person having refused or unable to give their non-opposition