Search for a rare disease

* (*) mandatory field

Other search option(s)

Suggest an update

(*) Required fields.


Only comments seeking to improve the quality and accuracy of information on the Orphanet website are accepted. For all other comments, please send your remarks via contact us. Only comments written in English can be processed.

Orphanet doesn't provide personalised answers. To get in touch with the Orphanet team, please contact

Information provided in your contribution (including your email address) will be stocked in .CSV files that will be sent as an email to Orphanet's teams. These emails might be conserved in the teams' mailboxes, in our backoffice servers but will not be registered in our databases (for more information see our section General Data Protection Regulation and data privacy (GDPR) and Confidentiality).

Captcha image

ABeta amyloidosis, Iowa type

Disease definition

A form of hereditary cerebral hemorrhage with amyloidosis characterized by age of onset between 50-66 years of age, memory impairment, myoclonic jerks, expressive dysphagia, short-stepped gait, personality changes, and lobar intracerebral hemorrhages. This subtype is due to a mutation in the APP gene (21q21.2), encoding the beta-amyloid precursor protein. This mutation causes an increased accumulation of amyloid-beta protein in the walls of the arteries and capillaries of the meninges, cerebellar cortex and cerebral cortex, leading to the weakening and eventual rupture of these vessels.


Classification level: Subtype of disorder
  • Synonym(s):
    • ABetaD23N amyloidosis
    • HCHWA, Iowa type
    • Hereditary cerebral hemorrhage with amyloidosis, Iowa type
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal dominant 
  • Age of onset: Elderly
  • ICD-10: E85.4+  I68.0*
  • ICD-11: 8B22.3
  • OMIM: 605714
  • UMLS: C5679881
  • MeSH: -
  • GARD: -
  • MedDRA: -

Detailed information

General public

Disease review articles

ERN produced/endorsed by ERN(s)   FSMR produced/endorsed by FSMR(s)
The documents contained in this web site are presented for information purposes only. The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment.