Teaching Video NeuroImage: Improvement in Motor Development After Start of Levodopa in Tyrosine Hydroxylase Deficiency

E. Janssen*, M. Oosterloo, E. Rubio-Gozalbo, K. van Gassen, J. Nicolai

*Corresponding author for this work

Research output: Contribution to journalEditorialAcademicpeer-review


A 7-month-old boy was referred with developmental delay and axial hypotonia (video 1). Screening for inborn errors of metabolism was negative and single nucleotide polymorphism array was normal (46,XY). Myotonic dystrophy (type 1) and spinal muscular atrophy were excluded. Whole exome sequencing yielded biallelic mutations in the tyrosine hydroxylase gene (c.698 G>A, p.Arg233His and c.1211C>T, p.Thr404Met). Subsequent CSF analysis revealed a significantly lowered homovanillic acid/5-hydroxyindoleacetic acid ratio, confirming tyrosine hydroxylase deficiency.1 Treatment with monotherapy levodopa resulted in profoundly improved motor development (video 1). After several weeks of treatment, the patient developed levodopa-induced dyskinesias (video 1),2 insomnia, and hyperactive behavior. All symptoms ameliorated with levodopa reduction.

Original languageEnglish
Pages (from-to)E540-E540
Number of pages1
Issue number5
Publication statusPublished - 3 Aug 2021

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