Congenital CAA or HCHWA




• Congenital CAA or HCHWA-D was formerly known as ‘Katwijk disease’ (Katwijk is a village on the North sea coast of the Netherlands).

• HCHWA-D means Hereditary Cerebral Hemorrhage With Amyloidosis-Dutch type. It is a congenital form of cerebral hemorrhage.

• HCHWA-D occurs in the Netherlands for a few families. The disease is characterized by the accumulation of the amyloid protein in the blood vessels of the brains.

• Accumulation of amyloid in the vessel wall makes the vessels vulnerable and this will lead to intracranial bleeding. It is remarkable, but still unexplained, that the amyloid accumulates mainly in the vessels of the brains and almost never anywhere else in the body.

• The first stroke usually occurs between the 45th and 65th year. The number of cerebral hemorrhages differs for each person. Patients get an average of three bleedings. HCHWA-D can be accompanied by dementia. Read more…

• The association HCHWA-D (formerly known as Katwijk disease) started a foundation: Dutch CAA Foundation. This foundation collects money to give research to slow down, prevent of cure CAA a boost.

Summary of the facts
• HCHWA-D is a genetic variant of CAA.
• In both CAA and HCHWA-D an accumulation of amyloid in cerebral vessels takes place.
• Accumulation of amyloid in the brain occurs with Alzheimer's disease.
• Dementia is a symptom that can occur with Alzheimer's disease, with CAA and with HCHWA-D.


The Dutch Leiden University Medical Center has a special outpatient clinic for people with hereditary cerebral angiopathies.

This page is a translation of the Dutch page which was created in collaboration with Association HCHWA-D, Katwijk disease.


Dutch: and

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