Tyrosinemia type II is a rare oculocutaneous disorder that in some individuals is also associated with developmental delay or other neurological problems. Bilateral keratitis and painful hyperkeratotic lesions of the palms and soles are the typical presenting lesions. Diagnosis is suggested by the clinical picture, elevated plasma tyrosine levels, and specific urinary metabolites. It is an autosomal recessive condition caused by mutations in the tyrosine aminotransferase (TAT) gene. Treatment is aimed at reducing plasma tyrosine levels and consists of a low-protein diet with age-appropriate amino acid (phenylalanine-free and tyrosine-free), vitamin, and mineral supplements. Significant maternal hypertyrosinemia is associated with a poor fetal outcome.
Tyrosinemia Type II