The establishment and utility of Sweha-Reg: a Swedish population-based registry to understand hereditary angioedema

Hereditary angioedema is a rare disease, that it may be life-threatening. Although the exact prevalence is unknown, current estimates suggest that it is 1/10,000–1/150,000 individuals. The low prevalence requires combined efforts to gain accurate epidemiological data on the disease and so give us tools to reduce morbidity and mortality, and improve quality of life of sufferers.Sweha-Reg is a population-based registry of hereditary angioedema in Sweden with the objectives of providing epidemiological data, and so creates a framework for the study of this disease. The registry contains individual-based data on diagnoses, treatments and outcomes.The present manuscript seeks to raise awareness of the existence of Sweha-Reg to stimulate the international collaboration of registries. A synthesis of data from similar registries across several countries is required to approach an inclusive course understanding of HAE.Hereditary angioedema (HAE) is a rare and potentially life-threatening condition that clinically manifests itself as acute attacks of facial, laryngeal, genital and peripheral swelling and/or recurrent abdominal pain, with a significant effect on the quality of life of sufferers [1]. The condition can have profound physical and psychological effects, which can prevent a normal social activity.The disease results from deficient production (HAE-I) or function (HAE-II) of C1 esterase inhibitor (C1-INH), and is caused by mutation of the C1NH gene on chromosome 11 [2]. To date, approximately 190 different C1NH mutations are known [3]. The disorder, which has an dominant hereditability, has traditionally been described in 2 types: HAE-I and HAE-II [4,5]. However, recently it has been proposed a third type (HAE-III), with normal C1-INH activity and unknown pathomechanism [6,7]. Although recent reports proposed increased activity of coagulation factor XII (Hageman factor) as a possible cause of HAE type III [8,9].Despite the substantial immunogenetic knowledge that has