Hereditary cerebral hemorrhage with amyloidosis

Hereditary cerebral hemorrhage with amyloidosis (HCHWA) is a neurological condition in which an abnormal protein (amyloid) builds up in the walls of the arteries of the brain (and less frequently, veins). This process is known as amyloid deposition, which can lead to strokes, seizures, neurological deficits, cognitive decline, and dementia. Symptoms usually present before the 5th decade of life.^[1] There are many different ways of classifying the types of HCHWA based on the underlying genetic changes, proteins involved, signs and symptoms, and the regions in which they were first described. Based on the region in which they were first described, the subtypes include:^[1][2]

• The Dutch, Arctic, Piedmont, Iowa, Flemish, Italian types are caused by mutations in the APP gene
• The British and Danish types are caused by mutations in the ITM2B gene
• The Icelandic type is caused by mutations in the CST3 gene 

All types of HCHWA currently described are inherited in an autosomal dominant manner.^[2] There is no cure for HCHWA, however, antihypertensive therapy is typically recommended.^[3][1]

"Familial" cerebral amyloid angiopathy is another term often used to refer to hereditary cerebral hemorrhage with amyloidosis. Hereditary cerebral hemorrhage with amyloidosis is the term more commonly used in the medical literature. Hereditary cerebral hemorrhage with amyloidosis, Dutch type is a specific form of hereditary cerebral hemorrhage with amyloidosis that is caused by a mutation (genetic change) in the APP (amyloid precursor protein) gene. There is at least one other form of hereditary cerebral hemorrhage with amyloidosis: the "Icelandic type," which is due to a mutation in the cystatin C gene.^[4]

To find out your chances of having hereditary cerebral hemorrhage with amyloidosis, you may want to speak with a genetics professional. A genetics professionl can review your medical and family history in order to provide you with your specific risks. To learn more about genetic consultations, click here.

To find a medical professional who specializes in genetics, you can ask your doctor for a referral or you can search for one yourself. Online directories are provided by GeneTests, the American College of Medical Genetics, and the National Society of Genetic Counselors. If you need additional help, contact a GARD Information Specialist. You can also learn more about genetic consultations from Genetics Home Reference.