Metabolic liver disease: Part 1

Abstract

The liver is known to have an expansive role in the synthesis, degradation, and regulation of pathways involved in the metabolism of carbohydrates, proteins, lipids, trace elements, and vitamins. Subsequently, abnormalities that affect these pathways as well as specific enzyme deficiencies often affect the liver either primarily or secondarily. The spectrum of liver injury results when there is absence or blockage of an enzyme in the metabolic pathway often resulting in accumulation of unmetabolized toxic substrates and/or deficiencies in essential substances normally produced distal to the dysfunctional enzyme. Clinical presentations of children with metabolic liver disease vary from acute, life-threatening illness in the neonatal period to a more indolent, chronic disease process that becomes evident in adolescence or adulthood. Disease progression often results from the failure of metabolic functions resulting in hepatocyte injury or cellular derangement and hepatomegaly with advancement to cirrhosis and/or tumor development. A detailed history can often elicit the possibility of a metabolic dysfunction and assist in the guidance of further clinical investigations while treatment is dependent of the particular metabolic defect that is identified.