Evidence map›Paper›PMID 40205187›Full record

SynthesisJournal of neurology2025

Skin α-synuclein assays in diagnosing Parkinson's disease: a systematic review and meta-analysis.

Yang Zhao, Mingyue Luan, Jing Liu, Qingqing Wang, Jianwen Deng, Zhaoxia Wang, Yunchuang Sun, Kai Li

Abstract readSystematic ReviewMeta-Analysis
PubMed Publisher
In one paragraph

Synthesis in Journal of neurology, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 14 papers.

0numbers the graph read from it
0cells of the map it votes in
14citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

14 citing papers in PubMed.

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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors.

Yang ZhaoDepartment of Neurology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China.
Mingyue LuanDepartment of Neurology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China.
Jing LiuDepartment of Neurology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China.
Qingqing WangDepartment of Neurology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China.
Jianwen DengDepartment of Neurology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China.
Zhaoxia WangDepartment of Neurology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China.
Yunchuang SunDepartment of Neurology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China. sychuang0805@163.com.
Kai LiDepartment of Neurology, Peking University First Hospital, No.8 Xishiku Street, Xicheng District, Beijing, 100034, China. kaili_neurologist@hotmail.com.ORCID http://orcid.org/0000-0003-3140-9688

Funding

National High Level Hospital Clinical Research Funding (Interdepartmental Research Project of Peking University First Hospital) 2023IR28National Key Research and Development Program of China 2023YFC3605200National Key Research and Development Program of China 2023YFC3605202
6 · The paper itself

Abstract

objectiveThis systematic review and meta-analysis evaluated the diagnostic performance of skin α-synuclein (α-syn) assays, focusing on key detection techniques.

methodsA comprehensive search of PubMed, Web of Science, Embase, and Cochrane Library was conducted on April 6, 2024. Bivariate mixed-effects models were used to calculate pooled sensitivity and specificity with 95% confidence intervals (CIs) for each group and subgroup.

resultsIn distinguishing Parkinson's disease (PD) from healthy controls (HCs) or non-neurodegenerative controls (NNCs), overall sensitivity and specificity were 0.78 (95% CI 0.75-0.80) and 0.96 (95% CI 0.94-0.97), with seed amplification assays (SAA) showing the highest sensitivity (0.89, 95% CI 0.85-0.93) compared to immunofluorescence (IF) (0.82, 95% CI 0.78-0.85) and immunohistochemistry (IHC) (0.70, 95% CI 0.66-0.74). For differentiating PD from multiple system atrophy (MSA), sensitivity remained high (0.80, 95% CI 0.76-0.83), but specificity was low (0.25, 95% CI 0.20-0.31); SAA, IF and IHC all obtained low pooled specificities (less than 0.3). Discriminating from tauopathies, the pooled sensitivity and specificity were 0.82 (95% CI 0.77-0.86) and 0.88 (95% CI 0.81-0.92), with immunological methods using phosphorylated α-synuclein (p-α-syn) outperforming those using non-phosphorylated α-synuclein (np-α-syn); SAA had a higher sensitivity than immunology techniques.

interpretationSkin α-syn assays, particularly SAA and p-α-syn immunological methods, demonstrate strong potential as diagnostic tools for PD; SAA had a higher sensitivity than immunology techniques. However, distinguishing PD from other α-synucleinopathies is still challenging and variability across methods highlight the need for standardization. Further research should focus on integrating skin α-syn detection with other biomarkers to enhance diagnostic precision.

Indexed as

alpha-SynucleinParkinson DiseaseSkinBiomarkersHumansSensitivity and Specificityalpha-SynucleinBiomarkersSNCA protein, humanDiagnostic test accuracyMeta-analysisParkinson’s diseaseSkin biopsyα-Synuclein

Identifiers

PMID40205187

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.