Pathology MCQ Answer 53

The Correct Answer is B

Jaundice, also known as icterus, is a condition which is characterised by a yellowish discolouration of the skin and the whites of the eyes. It is a symptom or clinical sign, not a disease by itself. The yellow colouration is caused by an excess amount of the bile pigment known as bilirubin in the body. Normally, bilirubin is formed by the breakdown of haemoglobin during the destruction of worn-out red blood cells. The pigment is then excreted by the liver into the bile via the bile ducts.

Cause and Pathogenesis

Excess amounts of bilirubin in the body can be caused by the overproduction of bilirubin, the failure of the liver cells to metabolise or excrete the bilirubin produced, or a blockage of the bile ducts. Overproduction of bilirubin may be caused by the destruction of an unusually large number of red blood cells, which occurs in a condition known as haemolytic anaemia. In this condition the liver cannot excrete the bilirubin which is formed more rapidly. This may occur in diseases such as malaria, thalassemia, and haemolytic disease (due to destruction of the red blood cells) of the new-born . Often, mild jaundice occurs as a common and normal condition in new-born babies because at birth there is both a deficiency in the enzyme that helps to eliminate bilirubin and also an increased breakdown of red blood cells (RBC) in the body. In babies, the condition generally disappears within a few days after birth as the enzyme is formed in the body. Sometimes, deficiency of this enzyme can also cause jaundice in adults. Jaundice may also result from various diseases or conditions that can affect the liver, such as hepatitis, cirrhosis, or cancer. A blockage of the bile ducts, may cause jaundice. The ducts may be blocked by various factors including inflammation and infection (cholangitis), gallstones (cholelithiasis), or cancer of the pancreas or the common bile duct.

The clinical types of jaundice include haemolytic jaundice which is due to the breakdown of RBC; hepatocellular jaundice caused by hepatic pathology due to viruses, drugs, alcohol abuse, etc; and Cholestatic jaundice due to biliary tract obstruction.

There are various strains of hepatitis viruses including hepatitis A (HAV), hepatitis B (HBV), hepatitis C (HCV), hepatitis D (HDV), and hepatitis E (HEV). Viruses F and G also exist and may cause primary hepatitis. HAV is transmitted by contaminated food and water and by the faecal-oral route; HBV and HDV are transmitted by contact with bodily fluids, HCV by percutaneous exposure to blood, and HEV, by contaminated water and by the faecal-oral route. Hepatitis A is seen most often in children and young adults, but the incidence is rising among those who are HIV positive. Hepatitis B affects all age groups and is associated with blood transfusion. Hepatitis C accounts for most transfusion-related cases. It is seen in all age groups. Hepatitis D is seen in individuals who are susceptible to HBV or may be HBV carriers, such as haemophiliacs and IV drug users. The disease manifestation is severe in children. Hepatitis E is seen primarily among young adults in developing countries. It is most severe in pregnant women. Congenital non-haemolytic hyperbilirubinemia such as Gilbert's Syndrome also causes jaundice. Sometimes certain drugs such as chlorpromazine (an anti-psychotic drug) may inhibit bilirubin excretion by the liver, causing jaundice.

Category: Pathology MCQs