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A new tyrosine hydroxylase genotype with orofacial dyskinaesia.

ABSTRACT: Tyrosine hydroxylase (TH) deficiency is a rare autosomal recessive and often treatable neurometabolic disorder with variable phenotypes. More than 20 pathological mutations have been identified in patients with TH deficiency. We report the case of a 10-month-old male patient who presented with developmental delay, hypotonia and oculogyric crises to the Salmaniya Medical Complex in Manama, Bahrain. At a later stage, he developed orofacial dyskinaesia and tremors with hyper-reflexia and clonus. A magnetic resonance imaging scan of the brain showed mild atrophy with widened ventricles and genetic testing revealed a novel homozygous mutation (c.938G>T; p.Arg313Leu) in exon 9 of the TH gene. The patient showed a remarkable response to treatment using combined levodopa-carbidopa. In this case, the orofacial dyskinaesia may be a specific clinical association unique to this novel mutation, which is the first to be described in Bahrain and the Middle East.

SUBMITTER: Al-Muslamani AM

PROVIDER: S-EPMC4117668 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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A new tyrosine hydroxylase genotype with orofacial dyskinaesia.

Al-Muslamani Ahood M AM Ali Fouad F Mahmood Fatima F

Sultan Qaboos University medical journal 20140724 3

Tyrosine hydroxylase (TH) deficiency is a rare autosomal recessive and often treatable neurometabolic disorder with variable phenotypes. More than 20 pathological mutations have been identified in patients with TH deficiency. We report the case of a 10-month-old male patient who presented with developmental delay, hypotonia and oculogyric crises to the Salmaniya Medical Complex in Manama, Bahrain. At a later stage, he developed orofacial dyskinaesia and tremors with hyper-reflexia and clonus. A ...[more]

PMID: 25097778

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