Clinical presentation and diagnosis of hereditary angio-oedema in five families.

The clinical features of 16 patients with deficiency of C1 esterase inhibitor are described. Severity ranged from no symptoms in 2 young subjects to repeated and severe abdominal pain and angio-oedema. Diagnostic techniques are described and the ease with which the diagnosis can be established is emphasized. A functional assay is required in addition to immunological determination of the protein in order to detect a minority of patients who have ineffective inhibitor. Experience of treatment with tranexamic acid is reviewed and its place in management in relation to androgens is discussed.