jaundice(redirected from prehepatic jaundice)
Also found in: Dictionary, Thesaurus, Medical.
jaundice(jôn`dĭs, jän`–), abnormal condition in which the body fluids and tissues, particularly the skin and eyes, take on a yellowish color as a result of an excess of bilirubin. During the normal breakdown of old erythrocytes (red blood cells), their hemoglobin is converted into bilirubin. Normally the bilirubin is removed from the bloodstream by the liverliver,
largest glandular organ of the body, weighing about 3 lb (1.36 kg). It is reddish brown in color and is divided into four lobes of unequal size and shape. The liver lies on the right side of the abdominal cavity beneath the diaphragm.
..... Click the link for more information. and eliminated from the body in the bilebile,
bitter alkaline fluid of a yellow, brown, or green color, secreted, in man, by the liver. Bile, or gall, is composed of water, bile acids and their salts, bile pigments, cholesterol, fatty acids, and inorganic salts.
..... Click the link for more information. , which passes from the liver into the intestines. There are several conditions that may interrupt the elimination of bilirubin from the blood and cause jaundice. Hemolytic jaundice is caused by excessive disintegration of erythrocytes; it occurs in hemolytic and other types of anemia and in some infectious diseases like malaria. Another type of jaundice results from obstruction in or about the liver; usually a stone or stricture of the bile duct blocks the passage of bile from the liver into the intestines. A third type of jaundice occurs when the liver cells are damaged by diseases such as hepatitis or cirrhosis of the liver; the damaged liver is unable to remove bilirubin from the blood. Treatment of jaundice is directed to the underlying cause. Many instances of obstructive jaundice may require surgery.
a yellow coloring of the body tissues in man, as a result of excess accumulation in the blood of the bile pigment bilirubin and of its metabolic products. Several types of jaun-dice are discerned, according to the mechanism of its origin—prehepatic and posthepatic.
Prehepatic jaundice is caused by an increased content of free bilirubin circulating in the blood, formed as a result of increased decomposition of the erythrocytes (hemolytic jaundice), or of congenital or acquired deficiency of enzymes that participate in binding bilirubin with glucuronic acid. Hemolytic jaundice appears in hemolytic disease of the new-born and in poisoning with hemolytic toxins; it is characterized by increased excretion of the products of bilirubin metabolism in the urine (urobilin) and feces (stercobilin, which causes the saturated pigmentation of the feces). Other types of jaundice caused by disruption in the capture and bonding of bilirubin and proceeding without substantive affection of liver cells are physiological jaundice of the new-born, nuclear jaundice, and juvenile jaundice. Hepatogenic jaundice (parenchymatous jaundice) is a function of organic (infectious, parasitic, or toxic) affection of the liver itself and is conditioned by the formation of an anastomosis between blood and bile capillaries and also by intrahepatic stasis of bile during inflammations of the liver. There appear, along with other symptoms of liver affection, a saturated pigmentation of the urine and faintly colored feces.
Posthepatic, or mechanical, jaundice develops due to disruption of the patency of the bile ducts, as a result of their stenosis or obstruction or from external pressure, and is manifested by the complete absence of stercobilin in the feces (colorless stools); it sometimes appears as a result of spasm of the sphincter at the point of influx of the bile duct into the duodenum. Pure forms of jaundice are not ordinarily found: in hemolytic jaundice, a mechanical component is added due to concentration of the bile and obstruction of the bile path-ways; affection of the liver cells is added to mechanical jaun-dice and it acquires some features of hepatogenic jaundice. As a result of the increased blood content of the bile components, jaundice is accompanied by itching, which is sometimes extremely distressing. In complete mechanical jaun-dice, there is disruption of the intestinal digestion and of fat and vitamin absorption, and the body is depleted of lime.
In a number of instances, a yellow coloring of the skin and other body tissues may be caused by pigments in food (for example, the carotene contained in carrots) or medications (acrichin).
REFERENCESBondar’, Z. A.Zheltukhi. Moscow, 1965.
Bondar’, Z. A. Klinicheskaia gepatologiia. Moscow, 1970.
A. S. MUKHIN