Tailoring of the diet for the individual in maple syrup urine disease: long-term home dietary treatment of an adult patient with MSUD by monitoring of daily intake with a personal computer. A case report.

The clinical appearance of maple syrup urine disease (MSUD) is due to reduced activity of the enzyme branched-chain alpha keto acid decarboxylase (alpha-BCKA-decarboxylase), thereby affecting the metabolism of the branched-chain amino acids (BCAA), leucine (Leu), isoleucine (Ile) and valine (Val). The aim of the therapeutic regime in MSUD is to keep the concentration of toxic metabolites within individual tolerance limits. The case of a 46-year-old female patient is reported. Energy expenditure was calculated by recording activities and indirect calorimetry. Nitrogen requirement and tolerance level of BCAA were estimated during parenteral nutrition with stepwise increasing supply of amino acids. A diet was designed within these limits, and a computer program was made to assist the patient in keeping her diet within the estimated limits.