diease

Jaundice


Jaundice overview and Definition

Bilirubin is a tetrapyrrole produced by the normal breakdown of heme. Most bilirubin is produced during the breakdown of hemoglobin and other hemoproteins. Accumulation of bilirubin or its conjugates in body tissues produces jaundice (ie, icterus), which is characterized by high plasma bilirubin levels and the deposition of yellow bilirubin pigments in the skin, sclerae, mucous membranes, and other less visible tissues.

 

Because bilirubin is highly insoluble in water, it must be converted into a soluble conjugate before elimination from the body. In the liver, uridine diphosphate (UDP)-glucuronyl transferase converts bilirubin to monoglucuronides and diglucuronides, referred to as conjugated bilirubin, which is then secreted into the bile by an ATP-dependent transporter. This process is highly efficient under normal conditions, so plasma unconjugated bilirubin concentrations remain low.

 

A large number of disease states lead to bilirubin accumulation in plasma. Diseases that increase the rate of bilirubin formation, such as hemolysis, or diseases that reduce the rate of bilirubin conjugation, such as Gilbert syndrome, produce unconjugated hyperbilirubinemia.

 

Diseases that reduce the rate of secretion of conjugated bilirubin into the bile or the flow of bile into the intestine produce a mixed or predominantly conjugated hyperbilirubinemia due to the reflux of conjugates back into the plasma. Elevated conjugated bilirubin levels usually indicate hepatobiliary disease.


Structure of Jaundice

The liver is located in the upper right-hand portion of the abdominal cavity, below the diaphragm, and on top of the stomach, right kidney, and intestines.

Shaped like a cone, the liver is a dark reddish-brown organ that weighs about 3 pounds.

There are 2 distinct sources that supply blood to the liver, including the following:

  • Oxygenated blood flows in from the hepatic artery
  • Nutrient-rich blood flows in from the hepatic portal vein

The liver holds about one pint that is 13% of the body's blood supply at any given moment. The liver consists of 2 main lobes. Both are made up of 8 segments that consist of 1,000 lobules (small lobes). These lobules are connected to small ducts (tubes) that connect with larger ducts to form the common hepatic duct. The common hepatic duct transports the bile made by the liver cells to the gallbladder and duodenum (the first part of the small intestine) via the common bile duct.

 


Pathophysiology

Conjugated hyperbilirubinemia results from reduced secretion of conjugated bilirubin into the bile, such as occurs in patients with hepatitis, or from impaired flow of bile into the intestine, as in patients with biliary obstruction. Bile formation is sensitive to various hepatic insults, including high levels of inflammatory cytokines, as may occur in patients with septic shock.

 

High levels of conjugated bilirubin may secondarily elevate the level of unconjugated bilirubin. Although the mechanism of this effect is not fully defined, one likely cause is reduced hepatic clearance of unconjugated bilirubin that results from competition with conjugated bilirubin for uptake or excretion.

 


 


Clinical signs & symptoms

Fever.

Chills.

Abdominal pain.

Flu-like symptoms.

Change in skin color.

Dark-colored urine and/or clay-colored stool

 


Differential Diagnosis

  • Blood test:

In blood test for liver the alpha fetoprotein levels may shoot up and this is considered as the tumour marker.

  • Angiogram:

During this test, a dye is injected into an artery to show liver tissue and any tumors.

  • Laproscopy:

The doctor uses a thin tube with a light (laparoscope) to observe the liver and other organs inside the stomach area.

  • Biopsy:

The removal of tissue for study under a microscope. It may be done using a laparoscope. A biopsy is the most reliable way to determine cancer.

  • CT scan: is shows the 3D images of the liver
  • MRI(magnetic resonance imaging):

It uses magnetic and radiofrequency waves to view the soft tissues. It alos used to reveal the metastasis of the cancer cells.

  • PET scan(positron emission tomography):

It also reveals the metastasis that the cancer cells has spread to the distant organ or not.

  • Bruising of the skin.
  • Spider angiomas (abnormal collection of blood vessels near the surface of the skin).
  • Palmar erythema (red coloration of the palms and fingertips).
  • Urinalysis (urine testing) that's positive for bilirubin shows that the patient has conjugated jaundice. The findings of urinalysis should be confirmed by serum testing. The serum testing will include a complete blood count (CBC) and bilirubin levels.
  • Your doctor will also do an exam to determine the size and tenderness of your liver. He or she may use imaging (ultrasonography and computer tomographic (CT) scanning) and liver biopsy (taking a sample of the liver) to further confirm diagnosis


Prevention

Avoid intake of alcohol

Maintain healthy lifestlyle.

Avoids hepatitis infection

Avoid consuming large amounts of alcohol

avoid overweight