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Tyrosinemia and intractable seizures

S S Seshia, T L Perry, K Dakshinamurti

    Epilepsia
    |August 1, 1984
    PubMed

    Insights

    This study reports a rare inherited disorder of tyrosine metabolism, tyrosinemia I, in a child with severe epilepsy and developmental delay. The findings highlight the critical role of tyrosine and methionine metabolism in the central nervous system.

    Area of Science:

    • Biochemistry
    • Genetics
    • Pediatric Neurology

    Background:

    • Inherited metabolic disorders can present with complex neurological and hepatic symptoms.
    • Tyrosinemia I is a rare genetic condition affecting tyrosine metabolism.
    • Early diagnosis and understanding of metabolic disturbances are crucial for patient outcomes.

    Observation:

    • A child presented with intractable seizures and developmental retardation from 10 months of age.
    • Jaundice and hepatosplenomegaly developed at 23 months, preceding death at 25 months.
    • Elevated methionine and tyrosine levels were observed in urine, plasma, cerebrospinal fluid (CSF), and brain tissue, with higher concentrations in the CNS.

    Findings:

    • The enzyme 4-hydroxyphenylpyruvate dioxygenase was undetectable in skin fibroblasts and liver.
    • Biochemical data strongly indicated an inherited disorder of tyrosine metabolism, specifically tyrosinemia I.
    • Metabolic disturbances in tyrosine and methionine within the central nervous system (CNS) were significant.

    Implications:

    • Tyrosinemia I should be considered in the differential diagnosis of children with unexplained epilepsy and neurological deficits.
    • Hepatic dysfunction developing in children on anticonvulsants warrants investigation for underlying metabolic disorders like tyrosinemia I.
    • The CNS impact of tyrosine and methionine metabolism disturbances in tyrosinemia I may be underestimated and warrants further research.

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