Background: Hereditary tyrosinemia type I is a disease with a severe prognosis. Main causes of death are acute liver failure, neurologic crises and hepatocarcinoma. NTBC, which acts as an inhibitor of the 4-hydroxyphenylpyruvate dioxygenase, prevents the formation of toxic metabolites involved in hepatic, renal and neurologic lesions.
Case reports: Results of NTBC therapy used in three infants with type I tyrosinemia who presented with acute liver failure are reported. The diagnosis relied on the finding of high plasmatic levels of tyrosine and methionine, and abnormal urinary excretion of succinyl acetone and delta aminolevulinic acid. Treatment with NTBC was initiated within 2 to 8 days from onset of symptoms. Signs of liver failure resolved after 3 weeks therapy. After 12 to 39 months of follow-up, outcome remains favorable.
Conclusion: The results reported here highlight the efficiency of NTBC in type I tyrosinemia with early acute onset. However, the long term outcome needs to be determined with regards to prevention of hepatocarcinoma and toxicity of the drug.