The phenomenon of high or elevated bilirubin is called in the medical and scientific field hyperbilirubinemia.
The bilirubin is a yellowish pigment originating from the degradation of hemoglobin present in the red blood cells, this occurs in the spleen . Then, this substance will pass to the liver to be conjugated and later it will be stored in the gallbladder where it will form part of the bile , which is excreted by this organ towards the duodenum (first portion of the small intestine) where it has to contribute with the adequate digestion of food, mainly of ingested fats.
Knowing this, Hyperbilirubinemia can be defined as the increase in bilirubin levels in the blood, normally we get 0.3 to 1 mg of bilirubin for each deciliter of blood but when the levels of this rise above normal the individual will begin to present signs of jaundice , since this pigment easily adheres to tissues, which is why it is common for the patient to turn yellow, especially their mucous membranes since they have a greater amount of elastic tissue.
The increase in bilirubin can be at the expense of direct or conjugated bilirubin which is that which has already been processed by the liver and is ready to be sent to the gallbladder to continue its functions or at the expense of indirect or unconjugated , which represents the bilirubin that is bound to the albumin molecule in the blood and has not yet undergone the proper degradation process to become part of the bile.
Causes of elevated bilirubin
To learn a little more about the subject, we will organize the causes into those that cause elevation of direct bilirubin and those that cause elevation of indirect:
Direct or Conjugated Hyperbilirubinemia
It usually originates in people with liver or biliary diseases that prevent the conjugation of bilirubin or its proper excretion.
- Acute hepatitis: this pathology can be caused by the hepatitis A virus or by other causes, what happens in this is that there is damage to the hepatocytes (functional unit of the liver) so that bilirubin cannot be transported from properly, thus passing into the bloodstream.
- Obstruction of the bile ducts: there are different reasons why the duct that carries bilirubin to the gallbladder could be obstructed, some of these may be cysts, swollen lymph nodes in the hepatic hilum, gallstones, inflammation of the bile ducts, tumors. , parasites, among others.
- Liver cirrhosis: it is fibrosis or scar formation in the liver tissue, which prevent the natural functions of the liver from being carried out .
- Dubin-Johnson syndrome : it is a genetic or inherited disease , where both parents must possess the gene and donate it to their child’s genetic load for it to manifest (Autosomal recessive) . What happens in this pathology is that there will be an elevation of bilirubin without evidence of alterations in liver or liver enzymes and without signs of hyperbilirubinemia at the expense of unconjugated bilirubin. In addition to this, the liver turns a dark color due to the accumulation of pigments.
- Rotor syndrome: like the previous one, it is a hereditary disease that both parents must suffer from and exactly the same thing happens except that in this the organ will not turn a darker color.
Indirect or unconjugated hyperbilirubinemia
- Hemolytic anemia: destruction of erythrocytes or red blood cells that causes the release of bilirubin into the bloodstream before it is metabolized.
- Bruise resorption
- Red blood cell production or ineffective erythropoiesis
- Transfusions: It is usually seen in people who have received large amounts of blood through transfusion.
- Gilbert syndrome: due to a genetic mutation, this disease is harmless in which the liver does not process bilirubin properly.
- Crigler-Najjar syndrome : it is another hereditary disease , in which there is a deficiency of the enzyme glucuronyltransferase , which intervenes in the metabolism of bilirubin. This causes an increase in the levels of this pigment in the blood without being in the presence of hemolysis.
The main symptom in increased bilirubin is jaundice, which refers to the yellowing of the skin and mucous membranes.
It is also common for the patient to refer dark, brownish urine, this is called coluria and is due to the passage of pigment into the urine.
Depending on the cause, gray or white stools may occur, because there is no passage of bilirubin to the digestive tract and therefore it does not reach the stool. Some patients even complain of generalized itching.