What Causes Hepatitis A?
Last reviewed: 23.04.2024
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The pathogenesis of hepatitis A
When hepatitis A is allowed to direct the cytopathic effect of the virus on the liver parenchyma. In view of this situation, the pathogenesis of the disease can be represented in the following form. The virus with saliva, food or water penetrates into the stomach and then into the small intestine, where it appears to be absorbed into the portal bloodstream and penetrates into the hepatocytes through the related receptor, where it interacts with biological macromolecules involved in detoxification processes. The consequence of this interaction is the release of free radicals, initiators of lipid peroxidation processes of cell membranes. The intensification of peroxidation processes leads to a change in the structural organization of lipid components of membranes due to the formation of hydroperoxide groups, which causes the appearance of "holes" in the hydrophobic barrier of biological membranes and, consequently, increases their permeability. There is a central link in the pathogenesis of hepatitis A - cytolysis syndrome. There is a movement of biologically active substances along the concentration gradient. In the blood serum, the activity of liver-cell enzymes with cytoplasmic, mitochondrial, lysosomal and other localization increases, which indirectly indicates a decrease in their content in intracellular structures, and consequently, a lower bioenergetic regime of chemical transformations. Violated all types of metabolism (protein, fatty, carbohydrate, pigment, etc.), resulting in a deficiency of energy-rich compounds and bioenergetic potential of hepatocytes decreases. The ability to synthesize albumin, clotting factors, various vitamins is impaired, glucose, amino acids are used for protein synthesis, complex protein complexes, biologically active compounds; the processes of transamination and deamination of amino acids are slowed down, difficulties arise in the excretion of conjugated bilirubin, cholesterol esterification and glucuronization of many other compounds, which indicates a sharp disturbance in the detoxifying function of the liver.