A rare hereditary angio-oedema characterised by potentially life-threatening episodes of subcutaneous and/or submucosal oedema without urticaria, associated with C1 esterase inhibitor (C1-INH) deficiency. Hereditary angio-oedema (HAE) type 1 is caused by quantitative, HAE type 2 by qualitative defects of C1-INH. The two subtypes are clinically indistinguishable. Patients may present at any age (but most commonly in childhood) with recurrent attacks of nonpitting oedema of the skin, severe abdominal symptoms such as pain and swelling, and/or respiratory distress due to upper respiratory airways involvement. Genital, bladder, muscle or joint swelling may occur in some cases. [from
SNOMEDCT_US]