The late onset form of C1 esterase-inhibitor deficiency presenting as food allergy.

Two cases of late onset recurrent angioedema associated with deficiency of C1 esterase inhibitor are described. Both patients had life-threatening episodes of angioedema that they had related to the ingestion of certain foodstuffs. This was not confirmed by food challenges or by food allergy skin testing, although both patients had embarked on strict exclusion diets before the diagnosis of C1 esterase-inhibitor deficiency. Clinicians should be aware of the entity of late onset angioedema caused by C1 esterase deficiency mimicking food allergy and hence delaying the diagnosis of this potentially lethal condition.