Obstructive Jaundice

Question 1

Stem

Answer 1

You are on-call for general surgery and are asked by the Emergency Department to see a 45-year-old female describes dark urine, and on examination she is jaundiced and has mild epigastric tenderness, Blood tests and patient. She complains of a 2-day history of epigastric pain, nausea and vomiting. On direct questioning she urinalysis results are available

Question 2

what type of jaundice is suggested by the blood results and urine analysis?

Answer 2

obstructive jaundice due to high enzymes( see the blood) and absent urobilinogen which is a laboratory finding in OJ

Question 3

In what forms does bilirubin circulate within the plasma?

Answer 3

Bilirubin circulates as free bilirubin( ie unconjugated )and conjugated to glucuronic acid (bilirubin diglucuronide).

Question 4

How are urobilinogens formed and how do they circulate?

Answer 4

Urobilinogens are formed by gut bacteria from bilirubin, with some excreted in feces and others reabsorbed into portal circulation.

Question 5

How does enterohepatic circulation maintain the bile salt pool?

Answer 5

Over 90% of bile salts are reabsorbed in the terminal ileum and returned to the liver for re-excretion, maintaining the pool.

Question 6

Why are Urobilinogens not detectable in urine in this scenario?

Answer 6

An obstruction to bile flow prevents bilirubin from reaching the gut, leading to undetectable Urobilinogens.

Question 7

What is the physiological role of bile salts?and how do they achieve the function?

Answer 7

They are crucial for the digestion and absorption of fats by emulsifying them and reducing surface tension.

bile salts aid in fat digestion and absorption as they produce micelles that keep lipids in solution and transport them to the intestinal brush border for absorption.

Question 8

What is the likely diagnosis for a patient with high temperature and rigors?

Answer 8

The likely diagnosis is acute or ascending cholangitis, which is an infection of the bile duct. Management should follow sepsis 6 protocols, including oxygen therapy, fluid resuscitation, and broad-spectrum antibiotics to cover Gram-negative organisms.

Question 9

What finding on an abdominal ultrasound can confirm obstructive jaundice?

Answer 9

Dilatation of intrahepatic and extrahepatic biliary ducts indicates obstructive jaundice.

Question 10

Which clotting studies will be abnormal due to bile salt reduction?

Answer 10

Prothrombin time will be prolonged and INR will be raised; vitamin K supplementation can correct this.

Question 11

Why might clotting be deranged in a patient with reduced bile?

Answer 11

Absence of bile leads to reduced absorption of vitamin K, decreasing production of vitamin K dependent clotting factors.

Question 12

What are the clinical consequences of reduced bile salts in the small intestine?

Answer 12

Fat malabsorption (steatorrhea) and poor absorption of fat-soluble vitamins (A, D, E, K).

Question 13

What are the causes of jaundice across pre-hepatic, hepatic, and post-hepatic categories?

Answer 13

Jaundice causes include:

Pre-hepatic: hemolytic anemia, autoimmune conditions like hereditary spherocytosis, transfusion reactions, and drug toxicity;

Hepatic: viral hepatitis, alcoholic liver disease, and congenital syndromes like Gilbert’s and Crigler-Najjar;

Post-hepatic: choledocholithiasis, biliary strictures, and extrinsic compression from tumors or pancreatitis.

Question 14

What is the name of the system responsible for bilirubin production?

Answer 14

Reticuloendothelial system

Question 15

What are the types of stents used in ERCP and their indications?

Answer 15

Plastic biliary stents (straight or pigtail) are indicated for :
benign biliary strictures needing temporary therapy.

bile leaks post-cholecystectomy.

malignant obstructions when metallic stents are unsuitable.

Self-expanding metal stents are used for :
palliation of malignant extrahepatic obstruction, especially when longer patency is desired.

Question 16

What are the complications associated with ERCP procedures?

Answer 16

Complications of ERCP include post-ERCP pancreatitis (the most common), bleeding (typically after sphincterotomy), infection such as cholangitis or bacteremia due to incomplete biliary drainage, and perforation of the duodenum or duct, which can lead to peritonitis.

Question 17

What are the blood findings associated with hepatic encephalopathy?

Answer 17

1. elevated plasma ammonia levels,

2.deranged liver function tests (LFTs) such as increased bilirubin,

3. prolonged PT/INR,
4. electrolyte imbalances like hyponatremia and hypokalaemia, indicating synthetic dysfunction and potential renal issues.

Question 18

What is the role of lactulose in managing secondary biliary cirrhosis?

Answer 18

Lactulose, as a non-absorbable disaccharide, reduces gut ammonia production and absorption by acidifying the colon and exerting a cathartic effect, which ultimately decreases the systemic ammonia load.