Jaundice and its types

• Jaundice is a clinical condition characterized by the yellow color of the white of the eyes (sclera) and skin.
• It is caused by the deposition of bilirubin due to its elevated levels in the serum.
• Hyper-bilirubinemia is often used to represent the increased concentration of serum bilirubin.
• The normal serum total bilirubin concentration is in the range of 0.2-1.0 mg/dl.
• Of this, 0.2-0.6 mg/dl is un-conjugated while 0.2-0.4 mg/dl is conjugated bilirubin.

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Types of jaundice

• It is considered to be a symptom rather than a disease which is also known as icterus.
• It is caused due to multiple factors so it is quite difficult to classify the jaundice.
• For the sake of convenience to understand the jaundice, it is classified into three major types. They are as follows:

i) Hemolytic jaundice

• This is generally associated with increased hemolysis of erythrocytes which may occur during incompatible blood transfusion, malaria and sickle cell anemia.
• This results in the over production of bilirubin beyond the ability of the liver to conjugate and excrete the same.
• Liver has got capacity to conjugate a large amount i.e. 3.0 g of bilirubin per day against the normal bilirubin production of 0.3 g/day.
• More bilirubin gets excreted into the bile leading to the increased formation of urobilinogen and stercobilinogen.
• This type of jaundice has various characteristics. They are:

1. Elevation of serum unconjugated bilirubin.
2. Increased excretion of urobilinogen in the urine.
3. Dark brown color of feces due to high content of stercobilinogen.

ii) Hepatic ( Hepato-cellular) jaundice

• This type is generally caused by the dysfunction of the liver due to damage to the parenchymal cells.
• This may be caused due to viral infection (viral hepatitis), poisons and toxins (chloroform, carbon tetrachloride, phosphorus, etc.), cirrhosis of liver, cardiac failure, etc.
• Viral hepatitis is the major one among these causes.
• The bilirubin uptake and its conjugation by liver cells is adversely affected by the damage to the liver.
• The various characteristics of hepatic jaundice are:

1. Both conjugated and unconjugated bilirubin level increases in the serum.
2. Dark colored urine due to excessive secretion 0f bilirubin and urobilinogen.
3. Activity of alanine transaminase (SGPT) and aspartate transaminase (SGOT) increases which are released into circulation due to damage to hepatocytes.
4. The patients pass pale, clay colored stools, due to the absence of stercobilinogen.
5. Nausea and anorexia might be experienced by the patients.

iii) Obstructive (regurgitation) jaundice

• Bile duct obstruction may lead to this type of jaundice which prevents the passage of bile into intestine.
• Gall stones and tumors can be the cause of obstruction.
• The conjugated bilirubin enters the circulation from the liver due to the blockage of bile duct.
• The various characteristics of this jaundice are as follows:

1. Concentration of conjugated bilirubin in serum increases.
2. The cells of the damaged bile duct release alkaline phosphatase due to which its level in serum elevates.
3. Elevated excretion of bilirubin in urine gives dark color to the urine and clay colored feces noticed due to absence of stercobilinogen.
4. Excess fat present in feces which indicates impairment of fat digestion and absorption in the absence of bile.
5. Nausea and gastrointestinal pain are noticed by the patients.

References: 

i) https://www.healthline.com/health/jaundice-types#hepatic-jaundice

ii) https://www.medcomic.com/medcomic/types-of-jaundice

Jaundice and its types