Dietary restrictions for phenylalanine and tyrosine are commonly recommended in addition to Nitisinone. Patients with HT-1 benefit from a reduced risk of liver and renal damage. Blood cell counts and plasma tyrosine levels must Hereditary tyrosinemia type 1 (HT-1), a rare genetic condition, is treated with nitisinone. It prevents the enzyme from generating harmful HT-1-related regularly assessed. Thrombocytopenia, leukopenia, and eye issues are typical adverse effects.


Tyrosinemia Type 1, a rare autosomal recessive genetic disorder, manifests in infancy with a range of symptoms.

  • These can include failure to thrive, diarrhea, vomiting, hepatomegaly (enlarged liver), jaundice, and a distinct odor resembling cabbage.
  • The disorder’s acute form exhibits rapid onset and intense symptoms, while the chronic form progresses more slowly.
  • Neurological crisis marked by severe pain, muscle tone changes, and more can also occur, contributing to the complexity of the condition.
  • Additionally, renal abnormalities like Fanconi syndrome and rickets may develop, affecting bone structure and function.


Tyrosinemia Type 1 arises due to mutations in the fumarylacetoacetate hydrolase (FAH) gene, which encodes the FAH enzyme. This enzyme is essential for the breakdown of tyrosine, an amino acid. A deficiency in FAH leads to the accumulation of tyrosine and its byproducts in various organs, primarily the liver, kidneys, and central nervous system. This accumulation triggers the array of symptoms and complications associated with the disorder.


Detecting Tyrosinemia Type 1 involves a thorough clinical evaluation, detailed patient history, and specialized tests. Symptoms like failure to thrive and hepatomegaly are often early indicators. Definitive diagnosis can be made by detecting tyrosine metabolites and succinylacetone in the urine, as well as by measuring FAH enzyme activity in liver tissue or cultured fibroblasts. Molecular genetic testing for FAH gene mutations can confirm the diagnosis. Newborn screening programs that measure succinylacetone in blood spots have also proven effective in early detection.


  • Timely intervention is crucial in managing Tyrosinemia Type 1. Treatment involves a multidisciplinary approach. Nitisinone, a medication that inhibits the buildup of toxic tyrosine byproducts, is a cornerstone of therapy.
  • Coupled with a low-tyrosine diet, nitisinone helps prevent the damaging effects of the disorder. For infants who have developed end-stage liver failure, liver transplantation may be necessary.
  • Early diagnosis and adherence to treatment have significantly improved survival rates and the overall quality of life for those affected by Tyrosinemia Type 1.