Year: 2019
Type: article
Abstract: Detecting and treating infants with biliary atresia (BA)2 earlier can reduce the need for liver transplant. As this case demonstrates, early detection has an important additional benefit: identifying treatable deficiencies of fat-soluble vitamins (vitamins A, D, E, and K). These vitamin concentrations are low in patients with cholestasis, because bile salts are required for their normal absorption. Low vitamin D concentrations, as seen in this patient, affect bone development and calcium absorption. Vitamin A deficiency is the leading cause of preventable blindness in children, and vitamin E deficiency is associated with neurologic disorders. Vitamin K deficiency is associated with the most acutely severe consequences. Vitamin K is used by the liver to produce procoagulant factors II, VII, IX, and X. Hence, low vitamin K in cholestatic infants results in prolonged prothrombin times and increased risk of bleeding, including life-threatening intracranial hemorrhage (1, 2). Fortunately, vitamin K deficiency (and the associated risk of bleeding) can be corrected efficiently with a dose of intravenous or intramuscular vitamin K. As an aside, the case discusses using direct bilirubin (DB) to total bilirubin (TB) ratios to distinguish cholestatic infants from those with physiological jaundice. DB:TB ratios <20% are thought to indicate physiological jaundice. However, in the first days of life, infants with BA can also have low DB:TB ratios. For example, in a small study, 79% of newborns with BA had increased DB concentrations, which were ≤20% of TB concentrations (3). Hence, clinicians should exercise caution when using DB:TB ratios, and they should avoid using DB:TB ratios in the newborn period to exclude BA. biliary atresia direct bilirubin total bilirubin.
Source: Clinical Chemistry
Authors: Price T Edwards, Sanjiv Harpavat
Institutions: Baylor College of Medicine, Texas Children's Hospital
Language: English
Subfield: Surgery
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W4249554027