Amyloid beta pathology might have been transmitted by contaminated neurosurgical instruments, a new study published in Acta Neuropathologica suggests.

Researchers studied the medical records of four people who had brain bleeds caused by amyloid beta build-up in the blood vessels of the brain. They found that all four people had undergone neurosurgery two or three decades earlier as children or teenagers, raising the possibility that amyloid beta deposition may be transmissible through neurosurgical instruments in a similar way to prion proteins which are implicated in prion dementias such as Creutzfeldt-Jakob disease.

Amyloid beta is best known for being one of the hallmark proteins of Alzheimer’s disease, but the researchers did not find evidence of Alzheimer’s in this study.

A separate review of the medical literature supported the discovery by identifying four other case studies with similar pathology and past surgical history. As these patients were all men with a history of head trauma, research teams had previously speculated that those were correlated.

The new study suggests otherwise, as all patients had a history of childhood neurosurgery, three were women and only one had a history of head trauma.

In a comparison group of 50 people of similar ages from the same archives, the researchers did not find any amyloid beta pathology and only three had a recorded history of childhood neurosurgery.

Previous work in laboratory animals has shown that tiny amounts of abnormal amyloid beta protein can stick to steel wires and transmit pathology into the animals’ brains, but this paper is the first to suggest the same may be possible in humans.

Paper: “Evidence of amyloid-β cerebral amyloid angiopathy transmission through neurosurgery”
Reprinted from materials provided by UCL.