Is cerebral white matter involvement helpful in the diagnosis of dentatorubral-pallidoluysian atrophy?

Dentatorubral-pallidoluysian atrophy: a case report and review of literature

BACKGROUND

Dentatorubral-pallidoluysian atrophy is a rare autosomal dominant neurodegenerative disease. It is a rare disease in the world. Therefore, sharing clinical encounters of this case can deepen global awareness and understanding of the disease.

CASE PRESENTATION

The patient was a 34-year-old male of Han nationality who was unmarried. The patient was admitted owing to weakness of the left lower limb with walking instability for 2 months and aggravation for 1 month. There was no dizziness, headache, numbness of limbs, convulsions, nausea, vomiting, abdominal pain, ataxia, nausea, vomiting, or abdominal pain. No nausea, vomiting, diarrhea, abdominal distension, tinnitus, hearing loss, fever, cough, expectoration. Personal history: worked in Cambodia 5 years ago, worked in Dubai 3 years ago, engaged in computer work, smoking or drinking habits. The patient was unmarried. Family history: the mother had symptoms similar to walking unsteadily (undiagnosed). Positive signs include a wide-base gait with a rotatory nystagmus that jumps upward in both eyes. Bilateral finger-nose instability test was quasi-positive, rapid alternating test was negative, and eye closure tolerance test was positive. Tendon reflexes were active in both upper limbs and hyperreflexia in both lower limbs. Stability of the heel, knee, and tibia. Genetic testing showed that the number of repeats in the dentatorubral-pallidoluysian atrophy ATN1 gene was 18 and 62, and the (CAG)n repeat sequence in the ATN1 gene was abnormal, with a repeat number of 62, and the patient was a pathogenic variant. The patient was diagnosed with dentatorubral-pallidoluysian atrophy. Dentatorubral-pallidoluysian atrophy remains a progressive neurodegenerative disease with no effective treatment. At present, the proband is taking 5 mg of buspirone three times a day, which has been reported to improve the symptoms. The patient was followed up for 6 months after taking buspirone, and there was no significant improvement in the temporary symptoms. At present, there are few cases of dentatorubral-pallidoluysian atrophy, and the characteristics of nystagmus in this disease have not been proposed in the past. This case reported the unusual presentation of nystagmus.

CONCLUSION

Dentatorubral-pallidoluygur atrophy is a rare neurodegenerative disease with autosomal dominant inheritance. To the best of our knowledge, our present case report is the first case report of dentatorubral-pallidoluygur atrophy with specific nystagmus. We describe the special eye shake and its positive signs to increase dentatorubral-pallidoluysian atrophy clinical positive signs.

The relationship between the number of CAG repeats and clinical manifestations: a survey of Chinese DRPLA family

OBJECTIVE

To describe the clinical, radiological, and genetic characteristics of a Chinese family with dentatorubropallidoluysian atrophy (DRPLA). Explore the distribution of CAG repeat size to the clinical features of patients.

METHODS

We collected the clinical symptoms and DNA analysis for the DRPLA gene was performed on the family members. DRPLA patients reported in the literature were reviewed to analyze the association between CAG repeat size and clinical features.

RESULTS

Six family members were confirmed by genetic analysis. The number of CAG repeat in the proband, her sister, her grandmother, her father, her uncle, and her cousin, was determined respectively as 63, 75, 50, 50, 50, 54. In our family, the sister of the proband had the earliest onset age and the most severe clinical symptoms, followed by the proband, and other family members showed no obvious clinical symptoms. Consistent with the conclusion of previous studies, the more repeats CAG, the earlier the age of onset and the severer phenotypes are.

CONCLUSION

We found six family members have CAG repeat expansion in the DRPLA gene on chromosome 12p13. Even in the same family, patients have different clinical presentations. The size of CAG repeats is negatively correlated with the age of onset and positively correlated with symptom severity. When the number of repeats is ≥ 63, the age at onset is < 21 years old, and obvious clinical symptoms generally appear. It seems to say the more repeats CAG, the earlier the age of onset and the severer phenotypes are.

LIMITATIONS

With a small number of cases in our family, the conclusion that the more CAG repeats, the earlier the onset and the more severe the clinical symptoms cannot be fully proved.

The cerebellar white matter lesions in dentatorubral-pallidoluysian atrophy

Dentatorubral-pallidoluysian atrophy (DRPLA) is an autosomal dominant neurodegenerative disorder caused by a CAG nucleotide repeat expansion in atrophin 1. A previous report described cerebellar white matter lesions on magnetic resonance imaging (MRI) in elderly-onset DRPLA patients, but this finding has not been fully investigated in a total population of DRPLA patients, including juvenile or early-adult onset patients. Herein, we attempted to determine the frequency, distribution pattern, and features of the cerebellar white matter lesions in 30 consecutive DRPLA patients. We also assessed the relationships between the cerebellar white matter lesions and clinical parameters and other MRI findings. The cerebellar white matter lesions were found in 43% of the 30 DRPLA patients, and in 70% of the late adult-onset DRPLA patients. In approx. Two-thirds of the patients with cerebellar white matter lesions, the lesions were localized in the paravermal area (paravermal lesions). Multiple logistic regression analyses revealed that the Fazekas grade of 'cerebral' white matter lesions was independently associated with 'cerebellar' white matter lesions. In conclusion, cerebellar white matter lesions are one of the distinctive MRI features in DRPLA patients, especially in patients with older age at onset. Cerebellar white matter lesions, as well as cerebral white matter lesions, might originate from the disease process of DRPLA itself, and they often have a characteristic distribution of paravermal lesions.

Dentatorubral-pallidoluysian Atrophy: An Update

Background

Dentatorubral-pallidoluysian atrophy (DRPLA) is a rare, autosomal dominantly inherited disorder characterized by myoclonus, epilepsy, ataxia, and dementia. Diagnosis is challenging due to the heterogeneous presentation and symptomatic overlap with other spinocerebellar ataxias. Symptoms vary according to age of onset, with a mean age at onset of 31 years. A CAG repeat expansion in the ATN1 gene results in neuronal intranuclear inclusions, variable neuronal loss, and astrocytosis in the globus pallidus, dentate and red nuclei. No disease-modifying or curative treatments are currently available

Methods

We performed an online literature search using PubMed for all articles published in an English Language format on the topics of DRPLA or ATN1 over the last 10 years. Where these articles cited other research as support for findings, or statements, these articles were also reviewed. Contemporary articles from related research fields (e.g., Huntington’s Disease) were also included to support statements.

Results

Forty-seven articles were identified, 10 were unobtainable and 10 provided no relevant information. The remaining 27 articles were then used for the review template: seven case reports, seven case series, six model system articles (one review article), four population clinical and genetic studies (one review article), two general review articles, and one human gene expression study. Other cited articles or research from related fields gave a further 42 articles, producing a total of 69 articles cited: 15 case series (including eight family studies), 14 model systems (one review article), 14 population clinical and genetic studies (two review articles), 10 case reports, eight clinical trials/guidelines, four genetic methodology articles, three general review articles, and one human gene expression study.

Discussion

DRPLA remains an intractable, progressive, neurodegenerative disorder without effective treatment. Early recognition of the disorder may improve patient understanding, and access to services and treatments. Large-scale studies are lacking, but are required to characterize the full allelic architecture of the disorder in all populations and the heterogeneous phenotypic spectrum, including neuroimaging findings, possible biomarkers, and responses to treatment.

Clinical and magnetic resonance imaging features of elderly onset dentatorubral-pallidoluysian atrophy

Dentatorubral-pallidoluysian atrophy (DRPLA) is an autosomal dominant spinocerebellar ataxia caused by CAG triplet expansion in atrophin 1 and is frequently associated with cerebral white matter lesions. To elucidate the clinical features of elderly onset DRPLA and the key radiological findings for differentiating DRPLA from physiological white matter lesions in healthy elderly subjects, we reviewed the clinical and magnetic resonance imaging (MRI) features of ten patients with elderly onset genetically confirmed DRPLA (> 60 years) and compared their MRI findings with those of age- and sex-matched ten healthy subjects with asymptomatic cerebral white matter lesions. The initial symptom was cerebellar ataxia in all DRPLA patients, and five of them did not have any symptoms other than ataxia at the time of MRI examination. Atrophy of the brainstem, superior cerebellar peduncle, and cerebellum was detected in all DRPLA patients and none of the healthy subjects. Abnormal signals in the brainstem (inferior olive, pons, and midbrain), thalamus, and cerebellar white matter were frequently observed in elderly onset DRPLA patients but not in healthy subjects. In conclusion, elderly onset DRPLA presents as cerebellar ataxia alone in the early stage of disease. Atrophy of the brainstem, superior cerebellar peduncle, and cerebellum and abnormal signals in the brainstem, cerebellum, and thalamus are key findings for differentiating elderly onset DRPLA from asymptomatic cerebral white matter lesions in healthy subjects.

Hereditary Cerebellar Ataxias: A Korean Perspective

Hereditary ataxia is a heterogeneous disorder characterized by progressive ataxia combined with/without peripheral neuropathy, extrapyramidal symptoms, pyramidal symptoms, seizure, and multiple systematic involvements. More than 35 autosomal dominant cerebellar ataxias have been designated as spinocerebellar ataxia, and there are 55 recessive ataxias that have not been named systematically. Conducting genetic sequencing to confirm a diagnosis is difficult due to the large amount of subtypes with phenotypic overlap. The prevalence of hereditary ataxia can vary among countries, and estimations of prevalence and subtype frequencies are necessary for planning a diagnostic strategy in a specific population. This review covers the various hereditary ataxias reported in the Korean population with a focus on the prevalence and subtype frequencies as the clinical characteristics of the various subtypes.