Jaundice - B. Pharma 2nd Semester Pathophysiology notes pdf

Jaundice

Content

•       Jaundice

•       Type

•       Pathophysiology

•       Diagnosis

Objective

At the end of this lecture, student will be able to

•       Summarize different types of Jaundice

•       Describe the pathophysiology

•       Explain the diagnosis of jaundice

Jaundice

Normal Range of Bilirubin

•       1～16mmol/l  (0.1 ～1mg/dl)
4/5 are unconjugated bilirubin, others  are conjugated bilirubin.

•       <1mg/dl       normal

•       1-2mg/dl       occult Hyperbilirubinemia

•       >2mg/ dl      jaundice Hyperbilirubinemia

Hyperbilirubinemia

Hyperbilirubinemia: the concentration of blood bilirubin are more than 1mg/dl.

Occult: the concentration of blood bilirubin are increased, but have no clinic sympotom, normally 1-2mg/dl.

Jaundice: (also called icterus) refers to the yellow color of the skin and scleare caused by deposition of bilirubin, secondry to increased bilirubin levels in the blood.

        Although not a disease itself, jaundice is usually a symptom of an underlying disorder.

Mechanism of Jaundice

Based on pathophysiology, jaundice may result from one or more of the following mechanism:

1. Increased bilirubin production (excessive red cell destruction)

2. Decreased hepatic uptake (ligandin, drug, prolonged starvation, and sepsis)

Decreased hepatic conjugation (enzyme,drugs, cirrhossis)

3. Decreeased excretion of bilirubin into bile (gallstone, tumour)

Simple Classification of Jaundice

•       Accordingly, a simple classification of jaundice is to divided into 3 predominant type:

①  Pre-hepatic (hemolytic jaundice)

②  Hepatic jaundice

③  Post – hepatic cholestatic (obstructive jaundice)

Hemolytic Jaundice

      massive lysis of red blood cells (for example, in patients with sickel cell anemia or malaria) may produce bilirubin faster than the liver can conjuagte it.

      More bilirubin is excreted into the bile, the amount of the urobilinogen entering the enterohepatic circulation is increased, and urinary urobilinogen is increased.

      Unconjugated bilirubin is elevated in blood.

Causes of Hemolytic Jaundice

Ø  Malaria

Ø  Side effects of certain drugs :antibiotic and anti-tuberculosis medicines, levodopa,

Ø  Certain drugs in combination with a hereditary enzyme deficiency known as glucose-6-phosphate dehydrogenase (G6PD)

Ø  Poisons Snake and spider venom, certain bacterial toxins, copper, and some organic industrial chemicals directly attack the membranes of red blood cells

Ø  Artificial heart valves

Ø  Hereditary RBC disorders sickle cell disease

Ø  Enlargement of the spleen

Ø  Diseases of the small blood vessels

Ø  Immune reactions to RBCs cancer

Ø  Transfusions

Ø  Kidney failure and other serious diseases

Hepatocellular Jaundice

•       Damage to liver cells (for example in patient with cirrhosis or hepatitis) causes a decrease in both bilirubin uptake and production of conjuagted bilirubin.

•       Unconjugated bilirubin occur in the blood and increased urobilinogen in the urine.

•       The urine is dark in color and stool are pale, clay color.

•       Level of AST and ALT are elevated and the patient experience nausea and anorexia.

Obstructive Jaundice

•       In this instance jaundice is results from obstruction of the bile duct.

•       The presence of a hepatic tumor or bile stone may block the bile ducts, preventing passage of bilirubin into the intestine, patients with obstructive jaundice experience GI pain, nausea and produce stools that are a pale, clay color.

Sample	Indices	Normal	Obstructive Jaundice	Hemolytic Jaundice	Hepatic Jaundice
Serum	Total Bil	＜1mg/dl	＞1mg/dl	＞1mg/dl	＞1mg/dl
	Direct Bil	0～0.8mg/dl	↑↑		↑
	Indirect Bil	＜1mg/dl		↑↑
Urine	Color	normal	deep	deeper	deep
	Bilirubin	—	＋＋	—	＋＋
	Urobilinogen	a　little	↓	↑	uncertain
	Urobilin	a　little	↓	↑	uncertain
Stool	Color	normal	Argilous (complete obstruction)	deeper	lighter or normal

Diagnoses of Jaundice

Summary

•       The main symptom of jaundice is a yellow discoloration of the white part of the eyes (sclera) and of the skin

•       Pre-hepatic jaundice is caused by anything which causes an increased rate of hemolysis

•       Hepatocellular (hepatic) jaundice can be caused by acute or chronic hepatitis, hepatotoxicity, cirrhosis, drug induced hepatitis and alcoholic liver disease

•       Complications of jaundice include sepsis especially cholangitis, biliary cirrhosis, pancreatitis, coagulopathy, renal and liver failure.