Successful dietary control of tyrosinemia II.

A Japanese girl, 2 years, 8 months of age, with palmoplantar keratosis and dendritic corneal opacities, showed increased tyrosine levels in the plasma, urine, and cerebrospinal fluid. The mental and physical growth was not retarded. The hepatorenal functions were within normal limits. Electron microscopically, the epidermal keratinocytes showed increased tonofibrils and no structures suggestive of tyrosine crystals. Cytosol and mitochondrial tyrosine aminotransferase (TAT) activities of the liver were greatly decreased, while p-hydroxyphenyl pyruvate oxidase (p-HPPO) activity was not decreased. The plasma tyrosine levels were controlled for 3 years with low phenylalanine-tyrosine diet.