Gilbert's syndrome in a patient with predominantly negative symptoms of schizophrenia

Idiopathic unconjugated hyperbilirubinemia (Gilbert's syndrome) is a common genetic enzyme deficiency found in 3-10% of the general population. It occurs with greater frequency in patients with schizophrenia. We report the case of a young man with mainly negative symptoms of schizophrenia in whom there has been little improvement in mental state with prolonged treatment despite an improvement in total bilirubin, contrary to other published cases. We examine the literature related to Gilbert's syndrome and symptom severity and we discuss the research into the pathophysiology of schizophrenia in Gilbert's syndrome and negative symptom schizophrenia.