Other acquired diseases

The National Prion Clinic also supports patients with other conditions caused by proteins being transferred between people. These conditions are different to acquired prion diseases, but people at risk of acquired prion diseases might also be at risk of these more recently described conditions. You can read more about acquired prion diseases here

Aquired Amyloid-Beta Disease

Amyloid-beta is a protein. It is associated with two diseases – Alzheimer’s disease, in which people develop dementia, and cerebral amyloid angiopathy, in which people develop brain haemorrhages.

In 2015, ground-breaking research from the National Prion Clinic showed that people who had died from iatrogenic CJD – an acquired prion disease caused by medical treatment (in this case, treatment with cadaveric human growth hormone ) – also had unusually high amounts of another protein, called amyloid-beta, in their brains. The authors concluded that the amyloid-beta protein had been transmitted to these people via their medical treatments. You can read the paper here. After this initial publication, several other institutions around the world reported similar findings.

Researchers from the MRC Prion Unit and National Prion Clinic later showed that historical samples of cadaveric human growth hormone contained measurable amounts of amyloid-beta protein, and could still be used to transmit amyloid-beta in an experimental model. You can read the paper here.

You can find out more about treatment with human derived pituitary growth hormone here

Iatrogrenic Cerebral Amyloid Angiopathy

We now know that a number of people have developed brain haemorrhages following medical treatments, often in childhood. These brain haemorrhages were caused by a condition called iatrogenic cerebral amyloid angiopathy, also called iatrogenic CAA.

Most cases of iatrogenic CAA have occurred after procedures using cadaveric dura. The dura is a tough membrane covering the brain and lying immediately under the skull. Material obtained from several dead patients was used during certain brain operations, and to treat abnormally growing blood vessels.  Since 1992 human dura grafts have not been used, having been replaced with a synthetic substitute.

Some people with iatrogenic CAA had brain operations which did not use cadaveric dura, and it is thought that they acquired amyloid-beta during the operation itself.

The National Prion Clinic is involved in a number of research studies that aim to better understand the causes and consequences of iatrogenic CAA. We work closely with the UCL Stroke Research Centre, which has extensive expertise in the diagnosis and treatment of brain haemorrhage, in trying to better understand this new condition. You can find out more about this research here