[Hereditary angioedema, a rare cause of recurrent abdominal pains. A report of 2 clinical cases and comments of a general nature].

Two clinical cases of recurrent abdominal pain are reported. These led to the unusual diagnosis of hereditary angioedema due to deficiency of C1 esterase inhibitor (C1-INH). The difficulties of identifying this genetic disease were caused by the variability of its clinical expression: the alteration of an autosomal dominant gene triggers angioedema attacks that may strike the cutaneous, gastroenteric and respiratory apparatus with differing intensity. Various subjects suffering from hereditary angioedema were found in the genealogical trees of the two patients, but all had extraintestinal symptoms of very variable intensity. Measurement of C4 and C1-INH made it is possible to identify in the first family a functional defect of C1 esterase inhibitor and in the second a quantitative defect in the same inhibitor.