Last Updated on February 4, 2024
Jaundice is a symptom complex that is characterized by the yellow coloration of tissues and body fluids due to an increase in bile pigment bilirubin and related products.
Jaundice is also known as icterus.
To understand the causes of jaundice, first, we need to learn about the metabolism of bilirubin.
Liver and Bilirubin Metabolism
Read in detail about the anatomy and function of the liver
Hemoglobin released by the breakdown of aged cells is broken down into globin and heme. The heme is further broken into iron and bilirubin. Bilirubin attaches to serum albumin and is transported to the liver where it is taken up.
In the liver, bilirubin is separated from albumin and conjugated to glucuronide by the enzyme glucuronyl transferase. The conjugated bilirubin is water-soluble and can be excreted by kidneys.
The conjugated bilirubin is excreted through the bile canaliculi and reaches the intestines where it is converted to stercobilinogen and urobilinogen by the intestinal bacteria. About 70% of this is absorbed in the colon and brought back to the liver and re-excreted (enterohepatic circulation). Unabsorbed stercobilinogen gives a brown color to the faces.
Circulating urobilinogen is carried to the kidneys for excretion in the urine as urobilinogen.
Hyperbilirubinemia and Jaundice

Hyperbilirubinemia means an increase in levels of circulating bilirubin in the blood. Increased, bilirubin levels after a threshold start getting deposited in the skin and other organs. Deposition of bilirubin in the skin, and mucous membranes leads to a yellowish tinge. This yellowish tinge is called jaundice. Thus High concentrations of bilirubin (hyperbilirubinemia), the bile product, and its congeners are responsible for yellow discoloration of skin in jaundice. They bind with circulating proteins.
Thus, jaundice is a symptom that indicates that bilirubin levels are increased. Liver function tests are a set of laboratory tests that look for levels of health and other parameters indicating liver health. Normal values related to bilirubin levels are
- Total bilirubin – <1 mg%
- Direct bilirubin – < 0.25 mg%
- Urinary bilirubin is present if direct bilirubin is greater than 0.4 mg% in serum.
- Urine Urobilinogen – 100-200 mg/day
- Fecal stercobilinogen – 300 mg/day
[Read about Liver Function Tests]
Hyperbilirubinemia may arise due to
- Increased bile pigment load to the liver.
- Affection of bilirubin diffusion into the liver cells.
- Defective conjugation.
- Defective excretion.
We will discuss various causes that may lead to jaundice.
Types of Jaundice
Prehepatic
Conditions that affect the breakdown of blood cells and lead to increased formation of bilirubin. Increased bilirubin spreads to tissues as the rate of formation exceeds the rate of uptake by the liver.
Hepatic
The liver has a condition that renders it conjugation or transport of bilirubin though the rate of formation of bilirubin is normal.
Posthepatic
The rate of formation and conjugation by the liver is normal but there is some obstacle in conjugated bilirubin.
Causes of Jaundice
Infections
- Viral hepatitis: Hepatitis means inflammation of the liver. Viral hepatitis means inflammation of the liver resulting from viral infection. Viral hepatitis could be acute or chronic.
- Hepatitis A, B, C, D, and E are viruses t
- Cytomegalovirus
- Epstein-Barr virus
- Yellow fever.
- Weil’s disease (Leptospirosis): Leptospirosis is a multisystem disease that involves the liver
- Septicemia: Septicemia or sepsis can quickly lead to tissue damage, organ failure, and death.
- Other Infections- Dengue, typhoid, salmonella, brucellosis
Toxic Injury
The liver plays an important role in the metabolism of drugs and other chemicals and becomes susceptible to injury from these agents. Apart from drugs, other chemicals may cause hepatotoxicity.
Common agents that may cause hepatic injury are
- Alcohol
- Acetaminophen and other NSAIDs
- Glucocorticoids
- Anti-tubercular drugs (rifampicin, PAS, isoniazid, thiacetazone)
- Amanita mushrooms
- Industrial toxins like arsenic, carbon tetrachloride, vinyl chloride, benzene Hexachloride
- Anesthetic agents- halothane
- Anticoagulants- phenindione
- Metals- arsenic, mercury, gold, bismuth
- Irradiations
Obstruction to Biliary Outflow
- Extra Hepatic Obstruction: It refers to an obstruction to the flow of biliary fluid from the liver to the intestine. Gallstones, duct strictures, cholecystitis, tumors of structures of the bile pathway, and biliary atresia
- Intra Hepatic Obstruction: Intrahepatic obstruction is an obstruction to the bile flow within the liver parenchyma. This may be caused by infective hepatitis and various drugs ( chlorpromazine, sulfonamides, methyltestosterone)
Hemolytic Causes
Hemolysis can leads to increased destruction of red blood cells which causes an increase in the production of bilirubin. Hemolysis may occur due to various reasons.
- Infections like malaria, clostridium welchi
- Drugs like methyldopa, quinine, phenacetin and sulfonamides
- Burns
- Irradiation
- Snakebite
- Mismatched blood-transfusion
- Paroxysmal Cold Hemoglobinuria
- Lymphoma
- Leukemia
- Systemic lupus erythematosus
- Uremia
Congenital Hyperbilirubinemia
This occurs because of the hereditary defect of enzymes taking part in the metabolism of bilirubin. It can be unconjugated and conjugated
- Unconjugated hyperbilirubinemia: Gilbert’s syndrome and Crigler-Najjar syndrome are types of unconjugated Congenital hyperbilirubinemia.
- Conjugated hyperbilirubinemia: Dubin Johnson syndrome and Rotor’s syndrome