Simple Skin Swab Could Diagnose Parkinson’s Disease

Simple Skin Swab Could Diagnose Parkinson’s Disease
Substantia nigra. Computer illustration showing a degenerated substantia nigra in Parkinson's disease. The substantia nigra plays an important role in reward, addiction, and movement. Degeneration of this structure is characteristic of Parkinson's disease. In Parkinson's neurons in the substantia nigra contain Lewy bodies, which are deposits of protein, shown here as small red spherical inclusions in the neuron's cytoplasm.

Researchers at the University of Manchester have developed a test that can diagnose Parkinson’s disease from sebum collected by swabbing the skin.

The test uses mass spectrometry and was able to identify 10 chemicals in the sebum skin swabs from Parkinson’s patients that differed from those without the neurodegenerative condition. According to a press statement, it was able to diagnose the disease with 85% accuracy.

“Not only is the test quick, simple and painless but it should also be extremely cost-effective because it uses existing technology that is already widely available,” said Perdita Barran, Ph.D., a professor at the University of Manchester who led the research.

“We are now looking to take our findings forwards to refine the test to improve accuracy even further.”

There is currently no conclusive preclinical test for Parkinson’s disease, which affects around 6 million people across the globe. It is normally diagnosed based on physiological changes and observations by physicians meaning that by the time a formal diagnosis is confirmed, much damage has already occurred to the brain’s dopaminergic neurons.

While there is not currently a cure for Parkinson’s, like many degenerative diseases, early diagnosis can help slow down progression. Treatments like levodopa or carbidopa are more effective if given early and other non-drug treatments like increased exercise can also help slow progression. An early stage, non-invasive test could therefore be very beneficial for those impacted by this disease.

A common non-motor symptom of Parkinson’s disease is seborrheic dermatitis, present in around 60% of those affected, where the skin produces abnormally high levels of oily sebum. To assess if sebum from Parkinson’s patients was different from healthy individuals Barran and colleagues carried out a mass spectrometry study.

“Studies of sebum are commonplace in dermatological conditions such as acne, however sebum as a biofluid has rarely been used in disease diagnostics,” write the researchers in the journal Nature Communications.

Sebum samples were taken from 80 Parkinson’s patients who had yet to start drug treatment, 138 medicated Parkinson’s patients and 56 healthy controls matched for factors like age and gender.

Overall, 10 chemical compounds were found to be present in significantly different amounts in Parkinson’s versus control participants. Except for one compound, the changes in the chemicals were very similar in treated and non-treated Parkinson’s patients versus controls.

These compounds are largely linked to lipid metabolism — the changes observed were in chemicals linked to the carnitine shuttle, sphingolipid metabolism, arachidonic acid metabolism and fatty acid biosynthesis.

Further work would be needed to confirm this, but the team believes the test they developed could also show disease changes over time and perhaps give an indication of prognosis. They are planning to create a spin-out company to commercialize and develop the test further.