Performing brain surgery places neurosurgeons at increased risk for acquiring transmitted Alzheimer’s disease, says Leslie Norins, MD, PhD, CEO of Alzheimer’s Germ Quest, Inc, based on his evaluation of five medical research reports.
Dr. Norins says these emerging clues challenge current teaching, which stresses Alzheimer’s disease is not transmissible.
He says his concern was aroused by a 2010 report in which the society of neurosurgeons presented the causes of death of its members. The death rate from Alzheimer’s disease was six times that from other causes. There was no explanation of this unusual finding at the time or since.
Dr. Norins notes that during operations these surgeons handle brain tissue with gloved hands, but accidental punctures can occur from sharp instruments. Infections from patients with hepatitis B and HIV have been transmitted to physicians via blood contact through glove punctures.
Also, he says, it is well established that tissues from infected animals can transmit organisms to workers who handle them, producing human diseases such as brucellosis, anthrax, avian influenza and bovine tuberculosis. Thus, infected brain tissue could transmit its infecting organism to an unprotected surgeon.
Dr. Norins says three scientific papers suggest amyloid-beta, a protein typically found in the brains of patients with Alzheimer’s disease, may be transmissible from one brain to another. He says that last month doctors reported on eight adult patients who suffered a brain hemorrhage from an uncommon cause—widespread amyloid-beta infiltrations.
What was most remarkable was that as a youngster each of the eight had a brain operation. The researchers theorized that amyloid “seeds” from other patients had contaminated surgical instruments subsequently used on the children. They believe that during surgery these agents were transmitted, and “grew” into the wider destructive amyloid pathology seen in them as adults.
In a 2016 study, four patients who received donor grafts of dura mater, the tough membrane that covers the brain, developed fatal brain hemorrhages due to disseminated amyloid decades after receiving their transplant. One possible explanation was that an infective amyloid agent had been carried over in the transplant.
A 2015 study reported amyloid-beta plaques developing in patients who received injections of growth hormone extracted from prion-contaminated human pituitary glands. Again, the possibility was raised that a transmitted agent, prion or fellow-traveler, was causing the amyloid plaques to develop in the recipients.
Finally, in 2010 it was reported that household caregivers of Alzheimer’s patients developed the disease themselves at six times the rate of caregivers of non-Alzheimer’s patients. This pattern was compatible with the possibility of limited transmission of Alzheimer’s within a household, perhaps requiring an extended period of intimate exposure.
However, the authors themselves did not consider this microbiological possibility. They speculated instead that the burden of caring for an Alzheimer’s patient produced so much stress in the caregivers that it rendered them somehow susceptible to Alzheimer’s themselves.
Considering these five reports together, Dr. Norins believes they show the risk of Alzheimer’s disease sometimes being transmitted accidentally to brain surgeons. Fortunately, he says, they are more protected and more cautious now than in earlier decades, because today’s surgical precautions are stricter due to the known threat of acquiring hepatitis B and HIV from patients.
Dr. Norins says it is no longer enough for authorities to merely repeat prior dogmatic assurances that Alzheimer’s cannot ever be transmitted. He maintains the question is not sufficiently settled. His solution? He urges more intensive research on the possible roles of microbes in Alzheimer’s disease be funded promptly.
Alzheimer’s Germ Quest, Inc., an independent organization, is the sponsor or the current $1 Million Challenge Award (ALZgerm.org) for the scientist who can submit persuasive proof that a microbe is the cause of Alzheimer’s disease.