ABSTRACT
Crigler-Najjar Syndrome is an uncommon genetic disorder characterized by the elevation of unconjugated plasmatic bilirubin secondary to deficiency of the enzyme uridine diphosphate glucuronyltransferase (UDP-GT). We report a 19-years-old woman with the syndrome diagnosed during the neonatal period, when she developed a severe jaundice in the first 10 days of life, reaching unconjugated bilirubin levels of 29 mg/dl, with normal liver function tests. After transient response to phototherapy, the patient was referred to a tertiary medical center in which an extensive work up ruled out other etiologies and the diagnosis of type I Crigler-Najjar syndrome was established. Currently, the patient has a mild mental retardation. She is receiving homemade phototherapy 18 h per day with acceptable control of bilirubin levels. Many mutations have been associated with UDP-GT dysfunction resulting in a broad spectrum of the disease. When bilirubin rises above physiological limits, it permeates the hematoencephalic barrier, inducing bilirubin impregnation of basal ganglia with secondary neuronal damage and necrosis. The worst outcome, kernicterus, is characterized by mental retardation, central deafness, ophthalmoplegia, ataxia, athetosis, spasticity, seizures and death. First line therapy includes phototherapy, but definitive therapy is liver transplantation before the occurrence of neurological damage.