Hyperbilirubinemia is a frequent condition affecting newborns during the first two weeks of life and when it lasts more than 14 days it is defined as prolonged jaundice. This condition requires differential diagnosis between the usually benign unconjugated hyperbilirubinemia and the pathological conjugated hyperbilirubinemia, that is mainly due to neonatal cholestasis. It is important that the ...

The aim of this study was to identify new pathogenic variations of the UGT1A1 gene in 11 patients diagnosed with neonatal unconjugated hyperbilirubinemia. We describe two cases in which clinically unapparent heterozygotic mutations in the UGT1A1 gene may become evident in combination with certain environmental conditions or additional genetic defects.

Severe unconjugated hyperbilirubinemia, seen mainly in neonates, may cause kernicterus and death. Conventional treatment for severe unconjugated hyperbilirubinemia consists of phototherapy and exchange transfusion. Phototherapy, however, has several known disadvantages while exchange transfusion is associated with a significant morbidity, and even mortality. These harmful effects indicate the n...

Normal full-term infants may have transient unconjugated hyperbilirubinemia that rarely exceeds 5 mg per 100 ml during the first 3 to 5 days of life (1, 2). This so-called physiologic hyperbilirubinemia is believed to result from delayed development of the hepatic glucuronide conjugating system (3-5), particularly glucuronyl transferase (6). Numerous factors, such as hemolysis, infection, drugs...

Faldaprevir, an investigational agent for hepatitis C virus treatment, is well tolerated but associated with rapidly reversible, dose-dependent, clinically benign, unconjugated hyperbilirubinemia. Multidisciplinary preclinical and clinical studies were used to characterize mechanisms underlying this hyperbilirubinemia. In vitro, faldaprevir inhibited key processes involved in bilirubin clearanc...

This study was carried out to analyze uridine diphosphate (UDP)-glucuronosyltransferase 1A1 (UGT1A1) gene mutations in neonates with unconjugated hyperbilirubinemia, from two different ethnic groups. Polymerase chain reaction and gene sequencing were used to analyze the differences in genotypes and allele frequencies of different gene mutations among the ethnic groups; this was followed by chec...

11 Background: The UGT1A1 gene encodes a responsible enzyme, 12 UDP-glucuronosyltransferase1A1 (UGT1A1), for bilirubin metabolism. Many 13 mutations have already been identified in patients with inherited disorders with 14 unconjugated hyperbilirubinemia, such as Crigler-Najjar syndromes and Gilbert’s 15 syndrome. 16 Case presentation: In this report, we presented a boy with intermittent 17 unc...

BACKGROUND The UGT1A1 gene encodes a responsible enzyme, UDP-glucuronosyltransferase1A1 (UGT1A1), for bilirubin metabolism. Many mutations have already been identified in patients with inherited disorders with unconjugated hyperbilirubinemia, such as Crigler-Najjar syndromes and Gilbert's syndrome. CASE PRESENTATION In this report, we presented a boy with intermittent unconjugated hyperbiliru...

In mammals, unconjugated bilirubin is rapidly cleared from the circulation and almost quantitatively excreted as a conjugate in the bile (2-4). The efficiency and rapidity of this process indicate that conjugation and subsequent biliary excretion represent the principal pathway of bilirubin disposition. If alternate pathways of bilirubin metabolism exist under physiologic conditions, their leve...