Jaundice and Bilirubin Metabolism

Questions and Answers

What does jaundice represent clinically?

Dark urine and pale stools

Increased RBC production

Yellowish discoloration of the skin and mucous membranes (correct)

Decrease in serum bilirubin levels

What is the normal serum bilirubin level in adults?

0.5 to 1.5 mg/l

1 to 2 mg/l

0.3 to 1 mg/l (correct)

0.1 to 0.5 mg/l

Which type of jaundice is caused by increased breakdown of red blood cells?

Post hepatic jaundice

Obstructive jaundice

Prehepatic jaundice (correct)

Hepatic jaundice

Which symptoms indicate obstructive jaundice?

Dark urine and pale stools Signup and view all the answers

What biochemical test is used to confirm jaundice?

Serum bilirubin test Signup and view all the answers

What is the function of bilirubin in the body?

Aid in digestion of fats Signup and view all the answers

What indicates the presence of conjugated bilirubin in urine?

Obstruction of the biliary channel Signup and view all the answers

What condition results in pale stools due to lack of bile in the gut?

Post hepatic jaundice Signup and view all the answers

What is a consequence of the absence of bile in the gut?

Deficiency of fat-soluble vitamins Signup and view all the answers

Which vitamin deficiency is indicated by fat malabsorption due to bile absence?

Vitamin K Signup and view all the answers

What kind of imaging is best for showing intra- and extra-hepatic bile channels?

Magnetic Resonance Cholangiopancreatography (MRCP) Signup and view all the answers

Which of the following is NOT a possible cause of obstructive jaundice?

Hepatitis infection Signup and view all the answers

What treatment is suggested for correcting coagulopathy in a patient with obstructive jaundice?

Injectable vitamin K Signup and view all the answers

What does the Courvoisier Law imply in a jaundiced patient?

If the gallbladder is palpable, stones are unlikely the cause Signup and view all the answers

What is a common diagnostic method for CBD stones in obstructive jaundice?

Endoscopic Retrograde Cholangiopancreatography (ERCP) Signup and view all the answers

Which of the following surgical procedures is suggested for CA head of the pancreas affecting obstructive jaundice?

Whipple operation Signup and view all the answers

Study Notes

Definition of Jaundice

Jaundice is clinically recognized by a yellowish discoloration of the sclera and mucous membranes.
Biochemically, jaundice occurs with serum bilirubin levels exceeding the normal range of 0.3 to 1 mg/l.

Bilirubin Metabolism

Breakdown of red blood cells (RBCs) releases iron and globin, with biliverdin transported to the liver.
In the liver, biliverdin is conjugated with two glucuronide molecules to form bilirubindiglucuronide, making it water-soluble.
Bilirubin is stored in bile, aiding in fat digestion, absorption of fat-soluble vitamins, and contributing to stool color.

Types of Jaundice

Prehepatic: Resulting from increased RBC breakdown.
Hepatic: Caused by liver diseases.
Posthepatic: Due to obstruction of biliary channels, also termed obstructive jaundice.

Clinical Presentation and Assessment

Initial examination to determine if the patient is truly jaundiced, including assessing scleral discoloration under sunlight.
Laboratory tests measure serum bilirubin levels to confirm jaundice.
Symptoms of obstructive jaundice include dark urine, pale stools, and itching due to bile obstruction.

Symptoms of Obstructive Jaundice

Dark urine indicates the presence of conjugated bilirubin, which is water-soluble.
Pale stools result from the lack of bile reaching the gut, affecting fat digestion and absorption.
Fat malabsorption leads to bulky, foul-smelling stools that do not flush easily.
Deficiencies of fat-soluble vitamins, especially vitamin K, occur, impacting coagulation.

Biochemical Assessment

Liver function tests are conducted to assess liver health and function.

Causes of Obstructive Jaundice

Common causes include:
- CBD stones
- Carcinoma of the head of the pancreas
- Carcinoma of ampulla of Vater
- Cholangiocarcinoma
- Iatrogenic causes such as ligation of CBD during surgery
- Intestinal worms migrating to CBD
- External pressure on CBD

Radiological Investigations

Ultrasound (U/S): Identifies CBD stones or obstructions and evaluates the caliber of CBD tumors.
CT Scan: Detects tumors in the pancreas or other structures causing obstruction.
MRCP: Excellent for visualizing intra- and extra-hepatic bile ducts.
ERCP: Offers both diagnostic and therapeutic approaches.

Treatment Strategies

General patient condition improvement through hydration and correcting vitamin K deficiency.
Prophylactic antibiotics to prevent infection complications.
Specific treatments based on obstruction causes:
- CBD stones may be removed via ERCP or surgery.
- Stenting may be used for cholangiocarcinoma or ampulla tumors.
- Whipple procedure or triple bypass surgery for pancreatic cancer management.

Clinical Insight

Courvoisier's Law: In jaundiced patients, if the gallbladder is palpable, it is unlikely that gallstones are the cause; this hints at possible inflammation or fibrosis from previous occurrences.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz covers the clinical definition of jaundice, including its biochemical basis related to serum bilirubin levels. Additionally, it explores the metabolism of bilirubin after the breakdown of red blood cells, detailing the biochemical processes that lead to its conjugation and storage in the liver.