Jaundice syndrome is manifested in the staining of the skin and mucous membranes in an icteric color, which is accompanied by other symptoms associated with the accumulation of excess bilirubin in the blood and other tissues. The main cause of jaundice is an imbalance between secretion and excretion of bilirubin. Jaundice is characteristic of pathologies of the hepatobiliary system and diseases that are accompanied by massive hemolysis of red blood cells. There are 3 types of jaundice, each of which has its own causes and features of manifestation. What are the main causes of jaundice?

Causes and mechanism of development of suprahepatic jaundice

Hyperbilirubinemia may be the result of increased secretion of bilirubin, weakening of bilirubin uptake processes and impaired transport of bilirubin by hepatocytes. According to this principle, jaundice is divided into hemolytic (suprahepatic), hepatic (hepatocellular, parenchymal) and subhepatic (obstructive, mechanical) jaundice.

Suprahepatic jaundice. Prehepatic jaundice is characterized by unconjugated hyperbilirubinemia, resulting from excessive production of bilirubin, which the liver is unable to fully conjugate and excrete. This develops under conditions of increased synthesis of bilirubin, which is associated with an increase in hemolysis and pathology of erythropoiesis. Prehepatic jaundice is accompanied by the presence of a large amount of indirect bilirubin in the blood plasma.

Unconjugated hyperbilirubinemia underlies enzymopathic jaundices, which are transmitted autosomal – dominant type. This is Gilbert's syndrome. In Gilbert's syndrome, there is no increase in transaminases, therefore it is called benign hyperbilirubinemia.

Causes of suprahepatic jaundice:

  • microspherocytosis;
  • glucose deficiency – 6 – phosphate dehydrogenase;
  • crescent – cellular anemia;
  • thalassemia, heteroimmune hemolysis;
  • ovalocytosis.

Hemolytic jaundice accompanies diseases of ineffective erythropoiesis (primary bypass hyperbilirubinemia, erythropoietic uroporphyria, B-12 deficiency anemia).

Causes and mechanism of development of hepatic jaundice

In gastroenterological practice, a large percentage of pathologies is occupied by hepatic jaundice. Hepatocellular (hepatic) jaundice is accompanied by mixed or conjugated hyperbilirubinemia. Causes of jaundice – viral lesions of the liver, infectious mononucleosis, leptospirosis, cirrhosis, chronic hepatitis, primary hepatocellular and metastatic liver cancer.

The pathogenesis of the development of hepatic jaundice is due to a violation of the processes of capture and conjugation of indirect bilirubin, which occurs against the background of damage to the integrity and permeability of hepatocyte membranes. As a result, conjugated hemoglobin enters the sinusoids and then into the blood plasma. Cholestasis can be provoked not only by a violation of the formation of bile, but also its excretion.

For hepatic jaundice, pathognomonic is an increase in the activity of liver tests (AlAT and AST), hypoalbuminemia, prolongation of the prothrombin time, a decrease in the prothrombin index.

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Main causes of subhepatic jaundice

In clinical practice, especially surgical, subhepatic cholestasis is more common, which is more often detected with the development of cholelithiasis or choledocholithiasis, with tumors of the head of the pancreas or the papilla of Vater. In such cases, jaundice is called mechanical.

Causes of obstructive jaundice:

  • Choledocholithiasis – one of the manifestations of gallstone disease. In the presence of stones in the hepatic duct or gallbladder, jaundice appears after a painful attack of hepatic colic. This is accompanied by skin itching, icteric coloration of the skin and mucous membranes, dark urine, feces become light.

Charcot's triad – jaundice, hepatic colic and fever. Bile, which continues to flow, fills the duct, its cavity increases, and the stone passes longer (valve obturation).

  • Stenosis of the major duodenal papilla – appears with cicatricial deformities of the papilla, inflammatory edema or tumor.
  • Neoplasms of the common bile duct – while jaundice appears after pain in the right hypochondrium and upper abdomen. Often the pain syndrome takes on the character of biliary colic.

When jaundice is detected in a patient, it is important to find out the cause of this condition, since the tactics of managing a patient with different types of jaundice are radically different.

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