A case of anorexia nervosa with hyperbilirubinaemia in a patient homozygous for a mutation in the bilirubin UDP-glucuronosyltransferase gene

Gilbert syndrome was diagnosed in a girl with anorexia nervosa and unconjug ated hyperbilirubinaemia. Since the patient was starved and hyperbilirubina emic, the loading test was not used for the diagnosis but analysis of the b ilirubin UDP-glucuronosyltransferase gene (UGT1A1) instead. The patient was homozygous for a missense mutation that replaced guanine with adenine at n ucleotide number 211 (211G-->A: G71R). The unconjugated hyperbilirubinaemia was apparently induced by the fasting state. Homozygous missense mutations of the gene have been generally recognized as responsible for Crigler-Najj ar syndrome type II; the results obtained here, however, confirm that Gilbe rt syndrome may also be caused by a homozygous missense mutation of UGT1A1. Conclusion Since anorexia nervosa patients are in a fasting state, they may show moderate unconjugated hyperbilirubinaemia if they have Gilbert syndro me. Gene analysis of such cases will rule out hepatic damage. Homozygous mi ssense mutations of the bilirubin-UDP-glucuronosyltransferase gene cause no t only Crigler-Najjar syndrome type II but also Gilbert syndrome.