Parkinson's disease is a very common neurodegenerative disease, affecting over 50 million people worldwide in 2013, recent data estimate. And who among us hasn't seen the shaking hands and shuffling gait typical of this debilitating condition? The bad news is the relentless progression of the disorder, with depression and dementia frequently developing. Now, as Rick and I discuss on PodMed this week and published in JAMA Neurology, an assay looking at a misfolded protein called alpha-synuclein may help in diagnosis, progression, and perhaps ultimately treatments or cure. And the study introduces to us a new technique for amplification of small amounts of protein, which we predict will have great clinical utility in lots of conditions.
The novel technology here is called 'protein misfolding cyclic amplification or PMCA,' and it takes advantage of the fact that misfolded proteins such as alpha-synuclein cause additional aberrant protein to form, thus allowing amplification of the signal to a detectable level. PMCA was utilized to detect alpha-synuclein in the cerebrospinal fluid of 76 people with known Parkinson's disease and 65 others with a different neurological disorder. In short, PMCA was 88.5% sensitive and 96.9% specific in identifying those with Parkinson's and was also correlated with symptom severity. As Rick and I also note, it would be great to have something other than CSF to test to render PMCA more practical, but this proof of concept study is heartening.
Other topics this week are all from NEJM: Revascularization of Left Main Coronary Artery Disease, Crizanlizumab for the Prevention of Pain Crises in Sickle Cell Disease, and Thromboprophylaxis after Knee Arthroscopy and Lower-Leg Casting. Until next week, y'all live well.
Diagnosing Parkinson's Disease,1 Comment