Dietary management of oculocutaneous tyrosinemia in an 11-year-old child.

An 11-year-old girl with keratitis and plantar keratosis had tyrosinemia. The concentration of tyrosine in the plasma was 16.5 mg/dL. Dietary intake of phenylalanine and tyrosine was systematically varied, and the plasma concentrations of tyrosine and nitrogen balance were studied. It was necessary to achieve a total intake of phenylalanine and tyrosine less than 100 mg/kg/day to obtain plasma concentrations of tyrosine of less than 10 mg/dL. After dietary therapy was started, the keratitis resolved promptly, and the patient remained asymptomatic during a period of 16 months in which the mean plasma concentration of tyrosine was 11.1 mg/dL. The dietary management of a child at this age presents a different problem from that of a young infant. It can be successfully pursued at home, as well as in the carefully regulated environment of a clinical research center.