Jaundice (icterus) is the name given to the yellow or yellow-green color of the skin and visible mucous membranes. Jaundice is the result of an increased amount of yellow bilirubin in the blood, which is not deposited in the skin but in all tissues and body fluids, but is most easily noticed on the skin. The color of bilirubin in the body is continuously formed by the breakdown of red blood cells. Red blood cells perform the most basic task of the blood - they carry oxygen. In a red blood cell, oxygen binds to the blood color, a blood pigment called hemoglobin. The lifespan of a red blood cell is 4 months on average. More than 100 million red blood cells die every minute, and bilirubin is formed from the hemoglobin of broken down bodies; most of it is excreted through the liver into the intestines. Bilirubin is a distinct yellow color: it paints the baby's stool gold. In adults, it is converted in the intestines, under the action of bacteria, into other chemical compounds, which then give the stool its characteristic brown color. One part of these chemical compounds is absorbed from the intestines into the blood and excreted in the urine. A more abundant accumulation of bile in the skin can cause many disturbances; there is a very strong itching of the skin, heart rate may slow down, due to colored eye water such patients see all things around them in yellow (xanthopsy).

Although the causes of jaundice are many and varied, there are three basic ones:
1. Jaundice occurs in all those diseases that lead to excessive breakdown of red blood cells. Sudden breakdown leads to the fact that an otherwise healthy liver cannot immediately process such a large amount of bilirubin, i.e. the liver cannot excrete bilirubin at the rate at which it enters the liver. The amount of bilirubin in the blood increases so it is deposited in the skin and other tissues. In most cases, jaundice is not very pronounced, and the color of the skin is yellow like straw. It is understandable that the resulting jaundice is accompanied by anemia due to a reduced number of red blood cells. The cause of this hemolytic jaundice may be an inherited weakness of red blood cells that break down well before normal blood cells. Decomposition can also be caused by bacteria in the blood that create toxins, which destroy red blood cells (sepsis). Strong and sudden decay is also caused by the cause of malaria. Hundreds of millions of red blood cells suddenly break down in occasional bouts accompanied by shivering. Some toxins are also dangerous for red blood cells. Their decomposition (hemolysis) regularly causes arsenic or arsenic gas poisoning. Jaundice is the main and most noticeable sign of poisoning by this poison.

2. Jaundice also occurs due to an obstruction in the flow of bile from the liver to the intestines, mainly in persons over 40 years of age. A mechanical obstacle that occurs suddenly and out of full health. Patients complain of sudden yellowing, but more often with pain in the upper abdomen, below the ribs on the right side. The most common cause of obstruction is gallstones that get stuck in the bile ducts accompanied by severe, cramping pain, but they can also be painless. In addition to stones, the bile duct can be blocked by a swollen bile duct mucosa due to inflammation. A large white worm or other parasite can also enter the bile duct and close the bile ducts. Due to bile stasis, the yellow color of bilirubin changes somewhat, so the skin has a greenish admixture. If the obstruction is complete, nothing bile enters the intestine; the stool becomes grayish-white, like clay or mortar. Mechanical obstruction of bile passage may develop gradually. The cause can be scars after inflammation, malignant and benign tumors of the liver, gallbladder, bile duct, pancreas, duodenum. Tumors and inflammation of the surrounding tissue can be the cause if they press on the bile duct from the outside; these can be cysts and enlarged lymph nodes in inflammation and malignancies. Prolonged bile stasis leads to severe changes in the body. The digestion of fats and other food ingredients is disturbed. Over time, liver damage and dysfunction of other organs of the body, such as the kidneys, occur.

3. The most common cause of jaundice is liver damage. The damage is mostly caused by infectious viruses, bacteria and parasites. Of all the inflammations, the most common cause of the virus is acute infectious inflammation of the liver (acute infectious hepatitis). The main transmission route of the virus: food and water. There is also inoculating hepatitis when the infection occurs exclusively through blood transfusion or insufficiently sterilized injection needles. With these inflammations, jaundice can last only a few days, in severe cases 6 weeks, and due to severe liver damage even longer. Yellow fever is common in the tropics of Africa and South America. Liver damage and jaundice are the main features of this disease: it is caused by a virus transmitted by a species of mosquito.

The largest number of liver damage is caused by the use of ethyl alcohol in the form of alcoholic beverages, wine, brandy, cognac. Alcohol is a poison that directly damages the liver. The liver of some people is particularly sensitive to alcohol, so the damage occurs quickly. Some people are more resistant and can take alcoholic beverages for years, but alcohol is the main culprit for the premature death of these people as well. Short-term jaundice can also be caused by some medications, eg due to taking sulfonamides, medications to treat tuberculosis, tablets to treat diabetes, some antibiotics; Some women are too sensitive to antibaby pills. Any case of jaundice must be reported to a doctor. Treatment is mandatory at the hospital. With today's diagnostic capabilities, a doctor can very quickly determine what type of jaundice it is. Once the diagnosis of the underlying disease that led to jaundice is made, treatment begins. Sometimes urgent surgical intervention is needed.

False jaundice is the yellow color of the skin that is not caused by an increase in the color of bilirubin in the blood. Yellow skin color can be caused by dyeing the skin with chemical agents that can get into the skin or blood or are applied externally to the skin; the most common cause is medications and food. Yellow skin may occur if large amounts of the drug atebrin are taken. At one time, along with quinine, it was the only anti-malarial drug, and today it is used very rarely. Yellow skin color is also caused by consuming larger amounts of food rich in carotene. Carotene is a precursor (provitamin) of vitamin A. Carotene is very abundant in carrots, which it gives a characteristic yellow and orange color. By consuming larger amounts of food that is high in carotene, it turns yellow first on the palms, soles and nostrils, and can affect the skin of the whole body. The skin is lemon-colored and unlike jaundice, it does not occur on the sclera. By stopping taking such food, the yellow color of the skin quickly disappears. People who have it more often may have a damaged liver and a disorder in the production of vitamin A from its pre-stage carotene.

More than 50% of newborns get a mild form of jaundice the second or third day after birth. On the fifth day, the yellow color is most pronounced, after which it gradually disappears. This form of jaundice is not dangerous for the child's health and is considered a natural, normal (physiological) phenomenon. Jaundice occurs due to the increased breakdown of red blood cells after childbirth. In the mother's womb, the baby has an increased number of red blood cells because the oxygen supply to the mother's blood is weaker than the amount of oxygen the body receives through respiration. When he begins to breathe, the baby receives significantly more oxygen than it received from the mother's blood, so a significant number of red blood cells are no longer needed. The breakdown of excess blood cells sharply increases the amount of bilirubin. Liver cells are not yet mature enough to break down and excrete the increased amount of bilirubin that comes into the liver. Due to that, its amount in the blood constantly increases and jaundice occurs. In 10 to 12 days at the latest, jaundice disappears even in the most severe forms. Any prolonged duration of jaundice above 12 days is a sign of the disorder and requires hospital treatment.

A life-threatening condition occurs if jaundice occurs in the first hours after birth. After 24 hours it is already very pronounced. Despite the fact that the child otherwise seems completely healthy, every case of early jaundice requires the most urgent transport to the hospital. More than 80 percent of such children have died before, and those who have survived are most often retarded in physical and mental development, some time to the point of complete idiocy. The main cause is mismatch of blood groups of mother and child, especially mismatch of Rh-factor. In rare cases, the cause may be differences in other blood groups. This condition occurs when an Rh positive fetus is found in an Rh negative mother. Injury or increased permeability of the placenta allows the Rh-positive factor to pass into the mother’s blood, the mother then produces a “defensive weapon” against a foreign blood group, the Rh-antibody. Antibodies destroy red blood cells that contain Rh-positive factor. In the same way that an Rh-positive factor came into a mother’s blood, so an Rh-antibody gets into a baby’s blood. The arrival of these antibodies in the bloodstream of a child is the cause of abortion and premature stillbirth. Especially a lot of antibodies get into the baby's blood during birth, so there is an increased breakdown of red blood cells in the first hours after birth.

Such a disorder does not occur in every pregnancy. It occurs more often in later pregnancies, since one or two healthy children have already been born. The cause is that the mother's blood in the first pregnancy does not produce enough antibodies. But even the first pregnancy can end in a “yellow baby,” even a dead baby, if the mother once received an Rh-positive blood transfusion. In order to prevent side effects, childbirth must be performed in a hospital if the mother is Rh negative and the father is Rh positive. Today’s diagnostic and treatment options have significantly reduced mortality and complications. The basis is the treatment of exanguinotransfusions. It is a procedure that replaces up to 90% of a newborn's blood in the first hours after birth. Blood is given from the umbilical vein, and medications are also given. Today, there is a possibility that in certain cases a blood transfusion is given to a child before it is born, while it is still in the mother's womb.