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

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

Authors' Contributions

A.S. and Sucheta collected the data and A.S. conceptualized the idea, wrote the manuscript, and is the first author. A.A. helped in case management and literature search. R.P. critically analyzed the manuscript.

Publication History

Received: 11 March 2023

Accepted: 24 April 2023

Article published online:
29 May 2023

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