Alternative treatment of cystinuria with alpha-merkaptopropionylglycine, Thiola.

Sixteen patients with cystinuria have been treated with Thiola for 0.5-4 years. Only two of the patients had recurrence of stones because of initial inadequate dose. The excretion of free cystine and the mixed Thiola-cysteine disulphide in the urine has been measured on an automatic amino acid analyser. Thiola has less side effects than D-penicillamine with respect to bone marrow, kidney, liver, gastrointestinal tract and skin. No chelating properties on urinary excretion of copper and zinc were observed during Thiola treatment. We conclude that successful treatment will depend on determining an individual dose of Thiola for every patient and from monitoring free cystine and Thiola-cysteine disulphide in the urine.