[Infowarrior] - Alzheimer's may be spread thru surgery

[Richard Forno]

Protein linked to Alzheimer's could be spread during surgery, say researchers

Ian Sample

Fragments of sticky proteins found in the brains of people with Alzheimer’s disease could potentially be spread to others via contaminated surgical instruments and other medical procedures, scientists warn. 

Researchers called for further work into the possibility that metal instruments used in medical procedures could pick up harmful proteins which survive conventional sterilisation with formaldehyde.

The concern comes after scientists found that a small number of people who died from Creutzfeldt-Jakob disease (CJD) after being treated with growth hormone taken from cadavers, developed brain changes seen in Alzheimer’s disease. 

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Doctors examined the brains of eight CJD patients who had received pituitary growth hormone, given predominantly to children with stunted growth until it was stopped in 1985. Six of the brains had an unusual build-up of protein called amyloid beta, which has long been linked to Alzheimer’s disease. The patients were aged 36 to 51 years old, but none carried gene variants that bring about the early onset of dementia.

John Collinge, director of the Medical Research Council Prion Unit at University College London, said the findings suggest that the hormone might have spread tiny pieces, or “seeds”, of amyloid beta, alongside the abnormal proteins, or prions, that gave people CJD. None of the patients developed Alzheimer’s disease, or other brain changes linked to the disease. They may never have done. Or they may have died before the symptoms had time to emerge.

Reporting their findings in the journal Nature, the scientists say the work should drive investigations into whether amyloid beta can be spread through other medical procedures, referred to as “iatrogenic routes” in the study.

“While there is no suggestion that Alzheimer’s disease is a contagious disease and no supportive evidence from epidemiological studies that Alzheimer’s disease is transmissible ... our findings should prompt consideration of whether other known iatrogenic routes of prion transmission, including surgical instruments and blood products, may also be relevant to amyloid beta,” the authors write.

Collinge told reporters that his team now suspected people could acquire amyloid beta “seeds” in three different ways: from a spontaneous, unlucky biological event, from a faulty gene or through a medical accident. He said there was no evidence that Alzheimer’s could be transmitted through blood transfusions, but added: “I think it’s not unreasonable to have a look. My concerns would be more to see if there is a risk of seeding from metal surfaces. I think that is something we ought to prioritise.” 

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http://www.theguardian.com/science/2015/sep/09/protein-linked-to-alzheimers-could-be-spread-during-surgery-say-researchers