How do you utilize skin punch biopsy to assess for alpha-synuclein in patients with parkinsonism?

Before starting autonomic training in Boston (with the creators of a test that looks for cutaneous synuclein/amyloid/small fiber density), I used the technique on several patients. It was actually quite helpful; one patient had an idiopathic autonomic failure (with several risk factors for it) and a question of very mild ataxia and another had years of poorly levodopa-responsive parkinsonism, mild cognitive issues, and relatively minimal autonomic signs/symptoms. The former was negative, suggesting his cardiac/diabetic/renal failure risk factors were to blame for autonomic failure. The latter was positive, thus suggestive of MSA-P, given a lack of significant and early cognitive decline.

Dr. @Dr. First Last mentions that sensitivity/specific...

This is mainly a research tool at this point. Keep in mind that the sensitivity and specificity of this test are not well established.

Please also see the answer to the following question for more thoughts on this topic:

https://www.themednet.org/question/19564

"What is the practical application of alpha-synuclein seed amplification assay CSF testing for the diagnosis and management of Parkinson's disease?".