Human prion diseases and the risk of their transmission during anatomical dissection

Abstract

Prion diseases (or transmissible spongiform encephalopathies) are a unique group of fatal progressive neurodegenerative diseases of the central nervous system. The infectious agent is hypothesized to consist solely of a highly protease-resistant misfolded isoform of the host prion protein. Prions display a remarkable degree of resistance to chemical and physical decontamination. Many common forms of decontamination or neutralization used in infection control are ineffective against prions, except chaotropic agents that specifically disrupt proteins. Human cadaveric prosection or dissection for the purposes of teaching and demonstration of human anatomy has a distinguished history and remains one of the fundamentals of medical education. Iatrogenic transmission of human prion diseases has been demonstrated from the inoculation or implantation of human tissues. Therefore, although the incidence of human prion diseases is rare, restrictions exist upon the use of tissues from patients reported with dementia, specifically the brain and other central nervous system material. A current concern is the potential for asymptomatic variant Creutzfeldt-Jakob disease transmission within the UK population. Therefore, despite the preventative measures, the transmission of prion disease through human tissues remains a potential risk to those working with these materials. In this review, we aim to summarize the current knowledge on human prion disease relevant to those working with human tissues in the context of anatomical dissection.

Human prion diseases: surgical lessons learned from iatrogenic prion transmission

“…The recommended prion decontamination protocols for reusable surgical instruments and surfaces recommended by WHO and CDC have been published and are readily available on CDC’s website (http://www.cdc.gov/prions/cjd/infection-control.html). 11 …”

“…88 The presence of prion-contaminated instruments in the operating room can pose a serious risk to health care providers and patients. 3,11 In the absence of strong evidence against a prion disease diagnosis in a neurosurgical patient, cautionary measures should be taken to prevent iatrogenic transmission of prions via the surgical instruments, as neural tissue presents the highest infectious burden of the disease. 8 …”

Imaging biomarkers for the diagnosis of Prion disease

“…2 The inherited human form of Prion disease (IPD) occurs as a result of one of more than 30 mutations in the prion protein gene (PRNP ), hence conferring various phenotypes to the disease, yielding to high heterogeneity. Variablity has also been reported among affected individuals within families carrying the same mutation.…”

An Update on the Hazards and Risks of Forensic Anthropology, Part I: Human Remains

“…Previously studied tissues are classified as having high infectivity, low infectivity, and no currently detectable infectivity. The most infective tissues of TSEs in humans include the following: brain, spinal cord, retina, optic nerve, spinal and trigeminal ganglia, and the pituitary gland . The infectivity of blood in cases of TSEs is still being debated, but if infective, blood is likely of low infectivity .…”