A skin-based test that may identify hallmarks of progressive supranuclear palsy (PSP), a rare neurological illness that impairs walking, balance, and swallowing, has been created by Canadian researchers.

According to the scientists from the University of Toronto and the University Health Network (UHN), the test may enable a quicker and more accurate diagnosis of PSP than is possible with existing techniques.

According to Ivan Martinez-Valbuena, a scientific associate at the Rossy Progressive Supranuclear Palsy Centre at the UHN, “this assay is important for assigning patients to the correct clinical trials, but it will be even more important in the future as researchers develop targeted, precision treatments for PSP.”

“In order to determine which patients would benefit the most from new treatments as they become available, diagnostic tools must be developed in tandem with them,” she said.

Although misfolded proteins in neurodegenerative illnesses have been successfully identified by researchers, the technology has not always been available, and some patients cannot have the surgery.

Because of this, patients are usually diagnosed based on their clinical appearance and symptoms, which means that some patients may get the wrong diagnosis, especially for rarer neurodegenerative disorders like PSP. Additionally, people with PSP can be mistakenly identified with Parkinson’s disease and enrolled in a trial that targets the incorrect protein, which might affect the outcomes of the study.

According to a recent edition of JAMA Neurology, the new test may identify a particular sequence of misfolded tau that is unique to PSP.

According to the findings, “disease-associated tau protein can be detected in the skin in living patients with high accuracy,” according to Gabor Kovacs, a professor of pathobiology and laboratory medicine at Toronto University’s Temerty Faculty of Medicine.

Furthermore, the scientists discovered misfolded tau in the majority of PSP patients but considerably less commonly in those with other neurodegenerative illnesses after analysing skin samples from patients with PSP, multiple system atrophy, corticobasal degeneration, Parkinson’s disease, and healthy controls.

Crucially, neither Parkinson’s disease patients nor healthy controls have misfolded tau protein. The assay’s overall sensitivity and specificity were 90 cent, according to the researchers.

To assist doctors in making more accurate diagnoses and suggesting more suitable clinical trials, Martinez-Valbuena said the test could be added to a panel of blood- and skin-based tests together with clinical data.