A Case of a Patient With MYH2-Associated Myopathy Presenting With a Chief Complaint of Hand Tremor.

Background: Postural tremor is an uncommon and often overlooked phenotype in skeletal myopathy, which may lead to diagnostic delays.

Case report: A 21-year-old man presented with adolescent onset postural hand tremor as the initial symptom, followed by mild limb muscle weakness. Neurological examination showed restricted ocular motility without diplopia and myopathic facial appearance. A muscle biopsy showed a decrease in type 2A fibers. Whole-exome sequencing identified two novel compound heterozygous variants in MYH2 gene (NM_017534.6): c.505+2T>C and c.3565 del C. The diagnosis was further validated via bioinformatics analysis and confirmed through familial co-segregation by Sanger sequencing.

Discussion: This report expands the mutational and phenotypic spectrum of MYH2-associated myopathy. We suggest that in the differential diagnosis of tremor, besides common neurogenic causes, myogenic etiology should also be considered.

Highlights: Hand tremor in this case expands the phenotype of MYH2-associated myopathy, enhancing our understanding of tremor origins. It underscores the importance of nuanced clinical assessment and genetic screening in complex tremor disorders.