[Clinical presentation and diagnosis of bradykinin-mediated angioedema]

Bradykinin-mediated angioedema is a rare disease causing painful, nonitching edema not responding to mast cell-directed therapy. Involvement of the upper airways can be life threatening.

Summary and overview of clinical manifestations and diagnostics of different types of angioedema to facilitate diagnosis.

Expert consensus and summary of current literature with presentation in the form of tables and algorithms.

The most important differentiation to make is between mast cell-mediated and bradykinin-mediated angioedema, whereby the latter group differentiates between hereditary and acquired, with and without C1-inhibitor(C1INH) deficiency and drug-induced angioedema, respectively. A special medical interview inquiring clinical symptoms, family history, drug intake, and response to therapy, but also laboratory testing for possibly low values of C4 concentration, C1-INH concentration and/or C1-INH activity help in diagnostics. In special situations, genetic sequencing can aid in diagnosing the very rare form of hereditary angioedema with normal C1INH. In the case of acquired angioedema with C1INH deficiency, often associated with low C1q and anti-C1INH-autoantibodies, a causative underlying disease should be ruled out or treated if present. Drug-induced angioedema, mainly caused by ACE inhibitors, shows normal laboratory results and subsides after terminating drug intake.

It is of utmost importance to differentiate and diagnose bradykinin-mediated angioedema in order to treat affected patients correctly.