Good pick-up in overt PD but a pretty invasive test to undergo... and may not so helpful in early disease... if ILBD is a precursor for PD it is a shame that so few of those cases had synuclein in the salivary glands...
J Parkinsons Dis. 2016 Jan 9. [Epub ahead of print]
Beach TG, Adler CH, Serrano G, Sue LI, Walker DG, Dugger BN, Shill HA, Driver-Dunckley E, Caviness JN, Intorcia A, Filon J, Scott S, Garcia A, Hoffman B, Belden CM, Davis KJ, Sabbagh MN.
BACKGROUND:
Clinical misdiagnosis, particularly at early disease stages, is a roadblock to finding new therapies for Lewy body disorders. Biopsy of a peripheral site might provide improved diagnostic accuracy. Previously, we reported, from both autopsy and needle biopsy, a high prevalence of submandibular gland synucleinopathy in Parkinson's disease (PD). Here, we report on an extension of these studies to subjects with dementia with Lewy bodies (DLB) and other Lewy body disorders in 228 autopsied subjects from the Arizona Study of Aging and Neurodegenerative Disorders.
OBJECTIVE:
To provide an estimate of the prevalence of histological synucleinopathy in the submandibular glands of subjects with PD and other Lewy body disorders.
METHODS:
Submandibular gland sections from autopsied subjects were stained with an immunohistochemical method for α-synuclein phosphorylated at serine 129. Included were 146 cases with CNS Lewy-type synucleinopathy (LTS), composed of 46 PD, 28 DLB, 14 incidental Lewy body disease (ILBD), 33 Alzheimer's disease with Lewy bodies (ADLB) and 2 with progressive supranuclear palsy and Lewy bodies (PSPLB). Control subjects included 79 normal elderly, 15 AD, 12 PSP, 2 CBD and 2 multiple system atrophy (MSA).
RESULTS:
Submandibular gland LTS was found in 42/47 (89%) of the PD subjects, 20/28 (71%) DLB, 4/33 (12%) ADLB and 1/9 (11%) ILBD subjects but none of the 110 control subjects.
CONCLUSIONS:
These results provide support for further clinical trials of in vivo submandibular gland diagnostic biopsy for PD and DLB. An accurate peripheral biopsy diagnosis would assist subject selection for clinical trials and could also be used to verify other biomarkers.
Encouraging to hear that LTS was found in PD patients, as the same group's previous feasibility study had suggested produced negative results (it was likely underpowered): http://www.ncbi.nlm.nih.gov/pubmed/24500652
ReplyDeleteI share your disappointment regarding the findings among the ILBD patients, but this research group have recently released an abstract suggesting the saliva gland pathology may actually be present relatively early on in the disease (<5 years)... though a biomarker of early disease is not the same as a biomarker of pre-symptomatic disease: http://www.ncbi.nlm.nih.gov/pubmed/26799362