Half‐life of CINH in hereditary angioneurotic oedema (HAE)*

Abstract
The half-life of 125I labelled C1INH was determined in patients with HAE and normal controls. There was no significant difference between these two groups. The half-life in the HAE patients was 67.7 hr +/- 4.9 hr (s.d.) and in the normals 64 hr +/- 1.4 hr (s.d.). This finding is consistent with a defect in synthesis as an explanation of the low serum C1INH levels in HAE patients.