Case Report
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Oct 6, 2021; 9(28): 8552-8556
Published online Oct 6, 2021. doi: 10.12998/wjcc.v9.i28.8552
Spinocerebellar ataxia type 3 with dopamine-responsive dystonia: A case report
Xiao-Le Zhang, Xiao-Bo Li, Fa-Feng Cheng, Shu-Ling Liu, Wen-Chao Ni, Fei-Fei Tang, Qing-Guo Wang, Xue-Qian Wang
Xiao-Le Zhang, Fa-Feng Cheng, Shu-Ling Liu, Wen-Chao Ni, Fei-Fei Tang, Qing-Guo Wang, Xue-Qian Wang, School of Basic Medical Sciences, Beijing University of Chinese Medicine, Beijing 100029, China
Xiao-Bo Li, Internal Medicine-Neurology, Xi'an Third Hospital, Xi'an 710000, Shaanxi Province, China
Author contributions: Zhang XL and Li XB contributed equally to this work, and were responsible for research conception and design, data collation and interpretation, and manuscript drafting; Cheng FF, Liu SL, Ni WC, Tang FF, Wang QG and Wang XQ revised the manuscript for important intellectual content and gave English writing guidance; all authors reviewed and approved the final version to be published.
Supported by the National Natural Science Foundation of China, No. 81874448 and No. 81973789.
Informed consent statement: Written informed consent was obtained from the patient for publication of this report and any accompanying images.
Conflict-of-interest statement: No potential conflicts of interest relevant to this article are reported.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CAREChecklist (2016).
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Xue-Qian Wang, MD, Chief Doctor, Professor, School of Basic Medical Sciences, Beijing University of Chinese Medicine, No. 11 Beisanhuandong Road, Beijing 100029, China. wxqbucm@126.com
Received: May 27, 2021
Peer-review started: May 27, 2021
First decision: June 24, 2021
Revised: June 28, 2021
Accepted: August 18, 2021
Article in press: August 18, 2021
Published online: October 6, 2021
Abstract
BACKGROUND

Spinocerebellar ataxia type 3 (SCA3) is a rare neurodegenerative disease with high genetic heterogeneity. SCA3 mainly manifests as progressive cerebellar ataxia accompanied by paralysis of extraocular muscles, dysphagia, lingual fibrillation, pyramidal tract sign, and extrapyramidal system sign. However, it rarely has clinical manifestations similar to Parkinson-like symptoms, and is even rarer in patients sensitive to dopamine. We report a patient initially diagnosed with dopamine-responsive dystonia who was ultimately diagnosed with SCA3 by genetic testing, which was completely different from the initial diagnosis.

CASE SUMMARY

A 40-year-old Chinese woman was admitted to hospital due to severe inflexibility. At the beginning of the disease, she presented with anxiety and sleep disorder. At the later stage, she presented with gait disorder, which was similar to Parkinson's disease. Her medical history was unremarkable, but her mother, grandmother, and uncle all had similar illnesses and died due to inability to take care of themselves and related complications. Laboratory and imaging examinations showed no abnormalities, but electromyography and electroencephalography revealed delayed somatosensory evoked potentials and slow background rhythm, respectively. Her symptoms fluctuated during the daytime, and we initially diagnosed her with dopamine-responsive dystonia. After treatment with low-dose levodopa, the patient’s symptoms were significantly improved, but the final genetic diagnosis was SCA3.

CONCLUSION

SCA3 has various clinical phenotypes and needs to be differentiated from Parkinson's syndrome and dopamine-responsive dystonia.

Keywords: Spinocerebellar ataxia type 3, Dopamine-responsive dystonia, Gene phenotype, Clinical phenotype, Differential diagnosis, Case report

Core Tip: We report a female patient initially diagnosed with dopamine-responsive dystonia. After treatment with low-dose levodopa, the patient’s symptoms were significantly improved, but she was ultimately diagnosed with spinocerebellar ataxia type 3 (SCA3) by genetic testing. Sensitivity to levodopa may be a clinical feature of SCA3, and this report could add to the evidence of the SCA3 clinical phenotypes, which need to be differentiated from Parkinson's syndrome and dopamine-responsive dystonia.