Bilirubin Metabolism — Preliminary Investigation

In our studies, high total bilirubin values in the plasma were noted in cases of Friedreich's ataxia. A bimodal distribution of the values indicated the possible presence of two subgroups of patients. In these kindred, we demonstrated an elevation in unconjugated bilirubin with features similar to those reported in Gilbert's syndrome: normal liver function tests, elevation after fasting and day to day variability. We also report preliminary experiments indicating that bilirubin levels may be taurine dependent. We postulate that the defect could be a secondary component of the ataxic disease, possibly indicating a defect in membrane transport.