Two cases of tyrosine hydroxylase deficiency with different phenotypes / 中华实用儿科临床杂志

ABSTRACT

The clinical characteristics, diagnosis and treatment, and the gene mutation of 2 different phenotypes patients developed with tyrosine hydroxylase deficiency (THD) were retrospectively analyzed.Case 1 was a severe infantile parkinsonism accompanied with motor retardation, which started with psychomotor retardation without dystonia in infantile period.Clinical symptoms were fluctuating.Case 2 was a mild dopa-responsive dystonia, which started with progressive lower extremity dystonia in school age.The genetic study revealed that both patients had heterozygous mutations in tyrosine hydroxylase ( TH) gene.Case 1 was compound heterozygous mutations in the TH gene at c. 457C>T(paternal) and c. 698G>A (maternal). Case 2 was compound heterozygous mutations in the TH gene at c. 457C>T(paternal) and c. 1481C>T (maternal). Both patients dramatically improved after the treatment with Levodopa.THD should be considered in any children with or without mental retardation presenting with fluctuations symptoms or fluc-tuations dyskinesia.Genetic testing is the most important diagnostic method.