Recurrent angioedema: diagnosis strategy and biological aspects

The aetiologies of recurrent angioedema (AE) comprise the frequent histaminergic AE and the rare bradykinin-mediated AE. Diagnosis must be done carefully because they do not have the same treatment. Diagnosis strategy is clinical. The most specific symptoms for bradykinin AE are: isolated AE without wheals, long duration of the attack, abdominal localisation. The unique useful biological tests for the diagnosis of bradykinin AE are C1Inh exploration which is altered in hereditary AE (HAE) types I and II. No other biological test is useful in clinical practice at present. In case of suspicion of bradykinin AE with normal C1Inh, physicians must think of drug-induced AE. Hereditary AE with normal C1Inh may be associated with a mutation on gene F12 in 20% of cases. For 80% of patients without mutation, the diagnosis must be done very carefully.