A Child with KMT2B-Related Acute-Onset Dystonia: Clinical Pointers to Molecular Diagnosis

Ankur Singh; Sucheta Sucheta; Abhishek Abhinay; Rajniti Prasad

doi:10.1055/s-0043-1769476

Journal of Pediatric Neurology, Inhaltsverzeichnis

Journal of Pediatric Neurology 2023; 21(06): 467-471
DOI: 10.1055/s-0043-1769476

Case Report

A Child with KMT2B-Related Acute-Onset Dystonia: Clinical Pointers to Molecular Diagnosis

Autor*innen

Ankur Singh

¹Division of Genetics and Metabolic Disorder, Department of Paediatrics, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
Sucheta Sucheta

²Department of Paediatrics, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
Abhishek Abhinay

²Department of Paediatrics, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India
Rajniti Prasad

²Department of Paediatrics, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India

Abstract

Dystonia is common extrapyramidal presentation of neurological problems in childhood. The causes could range from infectious, autoimmune, drug-induced, or genetic in origin. Genetic causes are rare in origin but could masquerade the common causes. Recently, KMT2B-related dystonia has been identified as a common genetic cause of dystonia in childhood. We present a case of a 3.5-year-old with 18 months of follow-up, who was diagnosed with KMT2B-related dystonia and managed with antidystonia drugs to an acceptable level where she could perform her day-to-day work with ease. Here, we highlight certain clinical pointers of the disease and the need of special genetic test in diagnosing such cases. We also tabulated the three previously reported Indian cases and compared their parameter with ours.

Keywords

dystonia - KMT2B - childhood

Volltext

Referenzen

References
1 Zech M, Boesch S, Maier EM. et al. Haploinsufficiency of KMT2B, encoding the lysine-specific histone methyltransferase 2B, results in early-onset generalized dystonia. Am J Hum Genet 2016; 99 (06) 1377-1387
2 Sanger TD, Chen D, Fehlings DL. et al. Definition and classification of hyperkinetic movements in childhood. Mov Disord 2010; 25 (11) 1538-1549
3 Meyer E, Carss KJ, Rankin J. et al; UK10K Consortium; Deciphering Developmental Disorders Study; NIHR BioResource Rare Diseases Consortium. Mutations in the histone methyltransferase gene KMT2B cause complex early-onset dystonia. Nat Genet 2017; 49 (02) 223-237
4 Carecchio M, Invernizzi F, Gonzàlez-Latapi P. et al. Frequency and phenotypic spectrum of KMT2B dystonia in childhood: a single-center cohort study. Mov Disord 2019; 34 (10) 1516-1527
5 Pandey S, Bhattad S, Panda AK, Mahadevan L. Late-onset KMT2B-related dystonia in an Indian patient with normal cognition, dystonic opisthotonus and lack of oromandibular and laryngeal involvement. Parkinsonism Relat Disord 2020; 74: 33-35
6 Padmanabha H, Awati AM, Thomas K, Sarma GK R. A novel mutation in KMT2B gene causing childhood-onset generalized dystonia with expanded phenotype from India. Neurol India 2021; 69 (05) 1400-1401
7 Rajan R, Garg K, Saini A. et al. Pallidal deep brain stimulation for KMT2B related dystonia in an Indian patient. Ann Indian Acad Neurol 2021; 24 (04) 586-588
8 Cif L, Demailly D, Lin JP. et al; Deciphering Developmental Disorders Study; Genomics England Research Consortium; NIHR BioResource; Undiagnosed Diseases Network. KMT2B-related disorders: expansion of the phenotypic spectrum and long-term efficacy of deep brain stimulation. Brain 2020; 143 (11) 3242-3261