Genetic architecture of a single cohort of 230 Indian Parkinson's Disease patients.

INTRODUCTION: Indian Parkinson's Disease (PD) patients are severely underrepresented in terms of genetic studies and little is known about the frequency of variants and their impact on motor and nonmotor symptoms (NMS). METHODS: This retrospective cross-sectional study was conducted in PD patients undergoing treatment at a tertiary care hospital from India. Patients were advised genetic testing if they had (i) age at onset (AAO) of motor symptoms at or before 50 years (EOPD), (ii) positive family history of PD, parkinsonism or dystonia. All patients underwent whole exome sequencing and potentially pathogenic variants were identified. RESULTS: Clinical and genetic data were available for 230 (163 males, 70.4 %) patients. Thirty-five pathogenic and likely pathogenic variants in various PD genes were identified in 47 patients resulting in a yield of 20.4 %. In the remaining, 82 patients had either variants of uncertain significance or had variants in genes not associated with parkinsonism and 101 patients did not have any non-benign variants. Patients with genetically mediated PD had a lower AAO and statistically greater frequency of dystonia (36.2 %), postural instability (29.8 %) and mood disorder (29.8 %) and a higher Hoehn and Yahr score (2.9). Among the 47 patients, 11 patients had PARK-PRKN, six patients had PARK-PLA2G6, and 22 patients had PARK-GBA1. CONCLUSION: Around one-fifth of early-onset PD can have an underlying monogenetic cause. PARK-GBA1, PARK-PRKN and PARK-PLA2G6 are the commoner causes of genetically mediated PD in India. Patients with genetic cause had an earlier age at onset, and more frequent dystonia, postural instability and dyskinesia.

Imaging Markers of Multiple System Atrophy and Their Association With Disease Severity: A Cross-Sectional Study.

Background Multiple system atrophy (MSA) is a rare, adult-onset neurodegenerative disorder marked by autonomic failure, parkinsonism, and cerebellar ataxia, with subtypes classified as parkinsonian (MSA-P), cerebellar (MSA-C), and autonomic (MSA-A). This study aims to identify MRI biomarkers for MSA and their correlation with disease severity. Methodology A total of 30 patients with probable MSA (20 MSA-C, 10 MSA-P) aged 45-65 years were studied. Motor and non-motor symptoms were assessed using the Unified Multiple System Atrophy Rating Scale (UMSARS), and all patients underwent 3T MRI brain imaging. Data analysis was performed using SPSS version 22 (IBM Corp., Armonk, NY, USA) with Spearman's correlation for clinical-imaging correlations. Results The mean age of the study population was 54.43 years, with a male predominance (56.7%). The most common symptoms included gait ataxia (43.3%) and urinary dysfunction (96.7%), with orthostatic symptoms in 33.3%. Moderate disease severity was observed, with mean UMSARS scores of 15.9 (Part 1) and 16 (Part 2), showing no significant subtype differences. MRI revealed abnormalities in all patients, predominantly cerebellar atrophy (90%). The "hot cross bun" (HCB) sign was seen in 75% of MSA-C patients, but none of MSA-P patients showed the same. The HCB sign was significantly correlated with severity in MSA-C (USMSARS-4). Putaminal signs were less frequent and slightly more prevalent in MSA-P, without significant clinical-imaging correlation. Conclusions This study reinforces the critical role of MRI biomarkers in the diagnosis of MSA patients. Notably, the HCB sign exhibited a significant association with clinical severity in MSA-C patients, while such correlation was absent in MSA-P cases.

A Qualitative Study Exploring Experiences in Caregiving for Patients With Advanced Wilson Disease.

ABSTRACT: BACKGROUND: Wilson disease (WD) is a rare disease characterized by impaired copper metabolism. It is usually diagnosed in children and has several distinct attributes that can make the caregiving experience different. The advanced stage of the illness is quite challenging, and caregiver experiences during this phase of the disease are underexplored. METHODS: The present study is an exploratory qualitative investigation with in-depth interviews aiming to understand the experiences of family caregivers of children with advanced WD receiving neuropalliative care services at a tertiary care hospital. Interviews from 7 family caregivers were recorded, transcribed, and analyzed using an inductive and interpretive approach. RESULTS: Family caregivers in the study were predominantly mothers. The major themes that emerged are: being a parent and the caregiver, uncertainty related to illness, financial implications, understanding the disease dynamics, constructive coping strategies, and extended family networks and societal influences. CONCLUSION: The experiences and the encounters of family caregivers of children with advanced WD are multifaceted. Their challenging experiences underscore the need for extended supportive services and neuropalliative nursing care to assist the caregivers and families, and navigate the process of treatment and rehabilitation for the child.

Clinico-genetic profile of seven patients with PARK-PINK1: A case series from a tertiary care centre from India and review of literature.

Background: Recessive variants in the PINK1 gene is a known cause of early-onset Parkinson's disease (EOPD). Objective: To describe the clinical features and genetic profile of patients of PARK-PINK1. Methods: Retrospective chart review of demographic, clinical and genetic details of patients carrying biallelic PINK1 variants from our database. Result: Seven cases were recruited with median age at onset 33 years (Range: 20-49). All had asymmetrical onset, tremor in four, abnormal posturing in two and slowness in one patient. Parkinsonism phenotype was noted in six patients (with dystonia in four) and isolated dystonia in one. Among 6 patients with parkinsonism, five had rest tremor, all had good levodopa-response, and four had motor-fluctuation with choreiform-dyskinesia. Exome-sequencing revealed bi-allelic pathogenic/likely pathogenic variants in all of which five were novel. Conclusion: PARK-PINK1 presents as an EOPD with tremor-predominant phenotype, good levodopa-responsiveness, early motor fluctuation and dyskinesia. We describe five novel variants in PINK1 gene.

Genetic heterogeneity of early onset Parkinson disease: The dilemma of clinico-genetic correlation.

With advances in genetic testing increasing proportion of early onset Parkinson disease (EOPD) are being identified to have an underlying genetic aetiology. This is can be in the form of either highly penetrant genes associated with phenotypes with monogenic or mendelian inheritance patterns or those genes known as risk factor genes which confer an increased risk of PD in an individual. Both of them can modify the phenotypic manifestation in a patient with PD. This improved knowledge has helped in deciphering the intricate role of various cellular pathways in the pathophysiology of PD including both early and late and even sporadic PD. However, the phenotypic and genotypic heterogeneity is a major challenge. Different deleterious alterations in a same gene can result in a spectrum of presentation spanning from juvenile to late onset and typical to atypical parkinsonism manifestation. Similarly, a single phenotype can occur due to abnormality in two or more different genes. This conundrum poses a dilemma in the clinical approach and in understanding the clinico-genetic correlation. Understanding the clinico-genetic correlation carries even more importance especially when genetic testing is either not accessible or affordable or in many regions both. In this narrative review, we aim to discuss briefly the approach to various PARK gene related EOPD and describe in detail the clinico-genetic correlation of individual type of PARK gene related genetic EOPD with respect to their classical clinical presentation, pathophysiology, investigation findings and treatment response to medication and surgery.

Exercise Habits in People with Parkinson's: A Multinational Survey.

BACKGROUND: Exercise has been demonstrated to result in improvements in physical function, cognition, and quality of life in People with Parkinson's (PwP) but its adoption is variable. OBJECTIVES: To investigate exercise preferences, levels, influencing factors among a diverse Parkinson's disease (PD) population, to understand exercise adoption patterns and plan informed interventions. METHODS: A cross-sectional survey collected data through online platforms and paper-based methods. The Exercise Index (ExI) calculated exercise level based on frequency and duration. RESULTS: Of 2976 PwP, 40.6% exercised regularly, 38.3% occasionally, and 21.2% did not exercise. The overall mean ExI was 18.99 ± 12.37. Factors associated with high exercise levels included exercising in groups (ExI 24-26), weightlifting (ExI 27 (highest)), using muscle-building equipment (ExI 25-26), and exercising at home following an app (ExI 26). A positive trend between ExI and varied exercise groups, locations, types, and equipment was observed. No expected benefit from exercise achieved the lowest ExI (8). Having at least two exercise-promoting factors, a bachelor's degree or higher, receiving exercise advice at initial visits, and aged ≤40 years at PD onset were strong predictors of exercise (adjust OR = 7.814; 6.981; 4.170; 3.565). Falls and "other" most troublesome PD symptoms were negative predictors (aOR = 0.359; 0.466). Barriers to exercise did not predict the odds of exercise. CONCLUSIONS: The study shows that PwP's exercise behavior is influenced by their exercise belief, age at PD onset, doctor's advice at initial visits, education level, symptoms, and exercise-promoting factors. High exercise levels were associated with certain types of exercises and exercising in groups.

The Clinical, Radiological and Genetic Spectrum of PLA2G6-Associated Neurodegeneration: An Experience From a Tertiary Center.

Background: Despite being the second most common type of neurodegeneration with brain iron accumulation, there is limited literature on PLA2G6-associated neurodegeneration (PLAN) within the Asian ethnicity, particularly in the Indian context. Methods: We conducted a retrospective observational study on patients with pathogenic/likely pathogenic PLA2G6 variants based on exome sequencing. Results: We identified 26 patients (22 families, 15 males) of genetically-confirmed PLAN with a median age of 22.5 years and age at onset of 13.0 years, encompassing various subtypes: infantile neuroaxonal dystrophy (5/26;19.2%), atypical neuroaxonal dystrophy (3/26;11.5%), dystonia-parkinsonism (5/26;19.2%), dystonia-parkinsonism-myoclonus (n = 4, 15.38%), early-onset Parkinson's disease (2/26;7.7%), complex dystonia (2/26;7.7%), and complicated hereditary spastic paraparesis (cHSP; 5/26;19.2%). The common initial symptoms included walking difficulty (7/26;26.9%), developmental regression (6/26;23.1%), and slowness (4/26;15.4%). Dystonia (14/26;53.8%), followed by parkinsonism (11/26; 42.3%), was the most common motor symptom. Non-motor symptoms included cognitive decline (12/26;46.2%) and behavioral changes (6/26;23.1%). Neuroimaging revealed cerebellar atrophy in 23/26 (88.5%) patients and claval hypertrophy in 80% (4/5) of INAD patients. Levodopa responsiveness was noted in 12 of 14 patients with parkinsonism/dystonia who received levodopa, and dyskinesia was noted in 10/11 patients. Genetic analysis revealed a total of 19 unique variants in PLA2G6 gene, of which 11 were novel. Twelve patients harbored the c.2222G>A variant, which is predominantly seen in Asian subpopulations. Conclusions: The study introduces 26 new patients of PLAN and 12 patients associated with the c.2222G>A variant, potentially forming the most extensive single center series to date. It also expands the phenotypic, neuroimaging, and genotypic spectrum of PLAN.

Journey through ARSACS: Insights from a case series of seven patients - A single centre study and review of Indian cohort.

Background: In this study we describe the clinical, and investigations profile of 7 cases of autosomal-recessive spastic-ataxia of Charlevoix-Saguenay (ARSACS). Methods: We performed retrospective chart review of genetically proven cases of ARSACS from our database. Additionally, we reviewed literature for reported cases of ARSACS from India. Result: All seven patients had onset within the first-decade. As per the available data, all had walking difficulty (7/7), spastic-ataxia (7/7), classical neuroimaging findings (7/7), sensory-motor demyelinating polyneuropathy (6/6), abnormal evoked-potentials (5/5) and thickened retinal nerve fiber layer (3/3). Exome sequencing revealed 8 pathogenic/likely-pathogenic unique variants (6 novel) in SACS gene. Additional 21 cases (18 families) of ARSACS that could be identified from India had similar clinical and investigational findings. The most common c.8793delA variant may have a founder effect. Conclusion: Our series adds to the previously reported cases of ARSACS from India and expands the genetic spectrum by adding 6 novel variants.

Quantification and Clinical Correlation of Posterior Cranial Fossa Cerebrospinal Fluid Volume in Primary Hemifacial Spasm Using Magnetic Resonance Imaging.

BACKGROUND AND OBJECTIVE: Primary hemifacial spasm (HFS) is caused by neurovascular conflict (NVC) at the root entry zone of the facial nerve. Whether reduction of posterior cranial fossa (PCF) cerebrospinal fluid (CSF) volume is a risk factor for HFS is not clear. The study aims at the radiologic assessment of PCF CSF volume and its clinical correlation. METHODS: A cross-sectional, hospital-based, case-control study was conducted, in which 50 cases of primary HFS and 50 age- and sex-matched controls were recruited. PCF CSF volume was quantified in 3-T brain magnetic resonance imaging. RESULTS: The mean age at presentation of cases was 50.7 ± 10.7 years (42-69 years) and controls was 52.4 ± 8.7 years (45-68 years). The mean duration of symptoms was 3.5 ± 1.3 years (1.5-8 years). About 52% of patients had grade 2 (mild) severity of HFS. The mean PCF CSF volume of patients was 13,725.1 ± 909.5 mm 3 and controls was 14,458.5 ± 973.5 mm 3 ( P < 0.001). The mean PCF CSF volume of females with HFS was 13,714.8 ± 852.5 mm 3 and female controls was 14,521.8 ± 973.5 mm 3 ( P = 0.006). PCF CSF volume was significantly associated with the presence of HFS ( P = 0.007), the severity of HFS ( P < 0.001), and the presence of NVC ( P = 0.02). CONCLUSION: PCF CSF volume was lesser in HFS patients and was associated with the presence of HFS, the severity of HFS, and the presence of NVC. Females with HFS had smaller PCF CSF volume. Small PCF CSF volume is a risk factor for HFS, particularly in females with HFS.

Ventrolateral medullary compression by vascular contact in primary hemifacial spasm: a radiological analysis.

BACKGROUND: The neurovascular conflict (NVC) causing hemifacial spasm (HFS) can also cause compression of ventrolateral medulla (VLM) which contains the central sympathetic neurons. VLM compression has been associated with hypertension. Whether the VLM compression in HFS patients is associated with hypertension is not clear. OBJECTIVE: To determine the frequency, severity of VLM compression and its association with hypertension in HFS patients. METHODS: A cross-sectional, hospital-based, case control study and recruited 120 study subjects (50 cases of primary HFS, 30 hypertensive and 40 normotensive age-, sex- matched controls). The VLM compression was assessed in magnetic resonance imaging Constructive Interference in Steady State (CISS) 3D sequences. RESULTS: Hypertension was present in 30 cases (60%). Six patients with HFS (20%) were detected to be hypertensive after the onset of HFS. VLM compression was seen in 24 cases (48%), 7 hypertensive controls (23.3%) and 5 normotensive controls (10%) (p = 0.03). Twenty-four patients with hypertension had VLM compression and remaining 6 patients with hypertension did not have VLM compression (80% vs 20%; p = 0.02). Normotensive patients did not have VLM compression. Vertebral artery was the most common artery causing VLM compression (22 patients; 7 hypertensive and 5 normotensive controls). CONCLUSION: VLM compression is more common in HFS patients as compared to hypertensive and normotensive controls. It is more common in hypertensive HFS patients in comparison with normotensive HFS patients. Microvascular decompression is an option in hypertensive HFS patients with VLM compression if the hypertension is medically refractory.

Revisiting Friedreich's Ataxia: Phenotypic and Imaging Characteristics.

Background and Aim: Friedreich's ataxia (FRDA) is a common cause of autosomal recessive cerebellar ataxia. The phenotype is dependent on the repeat size and duration of the disease. We aimed to study the clinical, electrophysiologic, and radiologic profiles in a large Indian cohort of genetically proven FRDA patients. Subjects and Methods: A retrospective cross-sectional, descriptive analysis of genetically proven FRDA patients was performed. A detailed review of all the hospital case records was done to analyze the clinical, radiologic, and electrophysiologic details. Results: A total of 100 FRDA patients were selected for the analysis. Eighty-six patients had an age at onset between 5 and 25 years. Eight patients (8%) were classified as late-onset FRDA and six patients (6%) as early-onset FRDA. The median age at presentation was 19 years. The median age at onset was 14 years, and the median duration of illness was 4 years. All patients had gait ataxia as the initial symptom. Gait ataxia, loss of proprioception, and areflexia were seen in all patients. Dysarthria, nystagmus, amyotrophy, spasticity, extensor plantars, pes cavus, and scoliosis occurred in one-third of patients. Cardiomyopathy (18%) and diabetes (5%) were less common. Sensory polyneuropathy (87.5%) was the most common nerve conduction abnormality. Cortical somatosensory evoked responses were absent in all 43 tested patients (100%). Brainstem auditory evoked response test was done in 24 patients and it showed absent reactions in six patients (25%). Visual evoked potential was tested in 24 patients and it showed absent P100 responses in five patients (21%). Cerebellar and cord atrophy was seen on magnetic resonance imaging in 50% of patients. Conclusion: Most FRDA patients (86%) had an age at onset of less than 25 years, with typical symptoms of gait ataxia, areflexia, and loss of proprioception found in all patients. Dysarthria, nystagmus, amyotrophy, spasticity, extensor plantars, pes cavus, scoliosis, cardiomyopathy, and diabetes were not seen in all patients. Cerebellar atrophy can occur in FRDA patients. Knowledge regarding the clinical, radiologic, and electrophysiologic profile of FRDA will aid in proper phenotypic characterization.

Generation of induced pluripotent stem cells (NIMHi015-A) from a Parkinson's Disease patient harbouring a homozygous Exon 3 deletion in the PRKN gene.

The Parkin (PRKN) gene mutation is prevalent in young-onset Parkinson's disease (PD), typically emerging before age 30, accompanied by early motor symptoms. Induced pluripotent stem cells (iPSCs) were derived from peripheral blood mononuclear cells of a PD patient with an exon 3 deletion in PRKN using Sendai-virus reprogramming. PD diagnosis was confirmed via the Unified Parkinson's Disease Rating Scale (UPDRS). Characterization of the iPSC line ensured self-renewal and pluripotency. This resource serves as a valuable platform for drug screening and elucidating the pathophysiology of this mutation, facilitating advancements in PD research.

Expanding the phenotypic and genotypic spectrum of DYT-TUBB4A with seven patients from India.

BACKGROUND: Variants in the TUBB4A gene are associated with dystonia (DYT-TUBB4A), Hypomyelination with Atrophy of the Basal Ganglia and Cerebellum (H-ABC) and spastic paraplegia. Phenotypes intermediate to these three broad phenotypes are also observed. These are rare disorders, and data from diverse populations remains limited. We report seven Indian cases with dystonia phenotype related to TUBB4A mutation. CASES: Among these seven patients, age at onset ranged from 5 to 48 years. Five patients had cranio-cervical onset of dystonia. One patient had prominent parkinsonism with dystonia. Patients responded well to botulinum toxin injected for laryngeal, cervical and jaw dystonia. The patient with parkinsonism responded well to levodopa, albeit with development of dyskinesias. Apart from the common p.Arg2Gly variant in three patients with DYT-TUBB4A, other variants included p.Arg262Pro, p.Arg39Cys and p.Asp245Asn. CONCLUSIONS: We report the first collection of cases with TUBB4A mutation from India. We expand the phenotype to include levodopa-responsive parkinsonism. Indian patients, consistent with global literature, harbor prominent adductor dysphonia, cervical and jaw dystonia, which responds well to botulinum treatment.

Clinical and Imaging Profile of Patients with Cerebrotendinous Xanthomatosis - a Video Case Series from India.

Background: Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive disorder caused by bi-allelic pathogenic variants in CYP27A1 gene that results in the deposition of cholestanol in the eyes, tendons, soft tissues and nervous system leading to cataracts, xanthomas, and various neuropsychiatric manifestations. The aim of our study is to describe the clinical, radiological and genetic profile of patients with CTX. Methods: This is a retrospective chart review of patients with CTX diagnosed based on classical clinical and radiological findings. The available clinical details, and investigations, including imaging, electrophysiological, pathological and genetic data, were documented. Results: Five patients (4 males) were recruited in the study. The median age at presentation was 32 years (range: 21-66 years). Walking difficulty was the most common symptom at presentation. All patients had cataracts, tendon xanthomas, eye movement abnormalities, dysarthria, pyramidal signs, ataxia and gait abnormality. Dystonia was noted in three patients. Palatal tremor and parkinsonism were noted in one patient each. In MRI brain, dentate, and corticospinal tract involvement were the most frequent imaging findings. Bilateral hypertrophic olivary degeneration was noted in one patient and hot cross bun sign in two. Three patients underwent genetic testing and all had pathogenic variants confirming the diagnosis. Discussion: CTX is a rare treatable disorder. Apart from the usual neurological presentation with spastic-ataxia, it can present at a later age with parkinsonism. Typical patterns of imaging findings are helpful in early diagnosis which aids in the treatment to prevent the neurological sequelae of the disease.

Association of Insulin-like Growth Factor-1 and Neurofilament Light Chain in Patients with Progressive Supranuclear Palsy.

Background: Progressive supranuclear palsy (PSP) is the most common primary tauopathy. The definite diagnosis of PSP is established by histopathologic changes in the brain. There are no reliable blood-based biomarkers to aid the diagnosis of this fatal disease at an early stage. Also, the precise etiopathology of PSP and its variants is inadequately understood. Objective: Blood-based molecules such as neurofilament light chain (NfL) and insulin-like growth factor-1 (IGF-1) are shown as important markers of neurodegenerative and aging processes, respectively. These two biomarkers have not been analyzed simultaneously in PSP patients. Methods: To address this knowledge gap, 40 PSP patients and equal number of healthy individuals were recruited and serum levels of NfL and IGF-1 were assayed in all the study participants by enzyme-linked immunosorbent assay (ELISA). Motor and nonmotor symptoms were evaluated in PSP patients using various scales/questionnaires. Cardiac autonomic function tests were performed in a subset of patients (n = 27). Results: A significantly high serum level of NfL (P < 0.01) and a reduced level of IGF-1 (P = 0.02) were observed in PSP patients compared to healthy controls. Besides, a negative correlation (r = -0.54, P < 0.01) between NfL and IGF-1 levels was observed in PSP patients. Conclusion: The finding of this study reinforces the important role of blood NfL level as a potential biomarker of PSP. Further, the current study provides novel insights into the reciprocal correlation between NfL and IGF-1 in PSP patients. Combined analysis of blood levels of these two functionally relevant markers might be useful in the prediction and diagnosis of PSP.