Diagnostic criteria and contributors to Gilbert’s syndrome

Abstract

Hyperbilirubinemia is a well-known condition in the clinical setting; however, the causes of elevated serum bilirubin are diverse, as are the clinical ramifications of this condition. For example, diagnoses of individuals vary depending on whether they exhibit an unconjugated or conjugated hyperbilirubinemia. Diagnoses can include conditions of disordered bilirubin metabolism (Gilbert's, Crigler-Najjar, Rotor, or Dubin-Johnson syndromes) or an acquired disease, including alcoholic/non-alcoholic fatty liver disease, hepatotropic hepatitis, cirrhosis, or hepato-biliary malignancy. Assessment of bilirubin concentrations is typically conducted as part of routine liver function testing. Mildly elevated total bilirubin with normal serum activities of liver transaminases, biliary damage markers, and red blood cell counts, however, may indicate the presence of Gilbert's syndrome (GS), a benign condition that is present in $5-10% of the population. In this case, mildly elevated unconjugated bilirubin in GS is strongly associated with "reduced" prevalence of chronic diseases, particularly cardiovascular diseases (CVD) and type 2 diabetes mellitus (and associated risk factors), as well as CVD-related and all-cause mortality. These reports challenge the dogma that bilirubin is simply a potentially neurotoxic by-product of heme catabolism and emphasize the importance of understanding its potential beneficial physiologic and detrimental pathophysiologic effects, in order to appropriately consider bilirubin test results within the clinical laboratory setting. With this information, we hope to improve the understanding of disorders of bilirubin metabolism, emphasize the diagnostic importance of these conditions, and outline the potential impact GS may have on resistance to disease.

UGT1A1 Variants c.864+5G>T and c.996+2_996+5del of a Crigler-Najjar Patient Induce Aberrant Splicing in Minigene Assays

“…The clinical outcome of a UGT1A1 deficiency relies on the residual activity of the UGT1A1 gene (OMIM#606433, Gene ID: 54658). In Gilbert's syndrome patients, UGT1A1 residual activity is ∼30% of the wild type activity, whereas in Crigler-Najjar type II and type I patients it is below 10 and 0%, respectively (Arias et al, 1969;Seppen et al, 1994;Kadakol et al, 2001;Maruo et al, 2016;Wagner et al, 2018).…”

A case of Gilbert’s syndrome diagnosis during pregnancy

“…Gilbert's syndrome (GS) is one of the cause of unconjugated hyperbilirubinemia and sometimes presented as mixed type. [1][2] It has an autosomal recessive inheritance pattern which results in deficiency of the enzyme uridine diphosphoglucuronate-glucuronosyl transferase 1A1 (UGT1A1). 2 The conjugation process of bilirubin to water soluble glucuronic acid is disrupted thus affecting its excretion into bile.…”

“…3 The prevalence of GS has been reported to be between 2% to20% for different populations with South Asian and Middle Eastern more prevalent than Europeans. 1,5 In addition, GS is more common in men than women in a ratio of 2 to 7:1. 4…”

Diagnosis of gilbert’s syndrome via pyrosequencing in clinical practice

“…Распространенность СЖ среди взрослого населения в мире вариабельна: от 2-5% [2,3] до 40% [4] -в европейской популяции; до 36% -в африканской [5]. У детей частота СЖ достигает почти 14% [6].…”