Gallbladder Disease - Gallstones

Question 1

What is a gallstone?

Answer 1

A small stone that forms within the gallbladder.

Question 2

Pathophysiology of gallstones (2).

Answer 2

1. Normally Cholesterol is solubilised in bile as a micelle with bile salts. An imbalance between the proportions of Cholesterol and Bile Salts lead to precipitation of the excess component as gallstones.
2. 75% Mixed (Calcium Salts, Bile Pigment and Cholesterol); 20% Cholesterol (Large Yellow); 5% (Bilirubinate (Small Pigmented).

Question 3

Clinical Presentation of gallstones.

Answer 3

1. Asymptomatic.
2. Biliary Colic.

Question 4

Complications of gallstones (6).

Answer 4

1. Acute Cholecystitis (>90%).
2. Ascending Cholangitis.
3. Pancreatitis.
4. Obstructive Jaundice.
5. Gallstone Ileus.
6. Gallbladder Cancer.

Question 5

Biliary System Anatomy (4).

Answer 5

1. Right Hepatic Duct + Left Hepatic Duct leave the liver and converge to form the Common Hepatic Duct.
2. Cystic Duct from gallbladder joins the Common Hepatic Duct halfway along to become the Common Bile Duct.
3. Pancreatic Duct from pancreas joins the Common Bile Duct at the Ampulla of Vater where everything drains into the duodenum.
4. The Sphincter of Oddi (ring of muscle that surrounds the ampulla of Vater to control the flow of bile and pancreatic secretions into the duodenum).

Question 6

What is Cholestasis?

Answer 6

Blockage to the flow of bile.

Question 7

What is Cholelithiasis?

Answer 7

Presence of gallstones.

Question 8

What is Choledocholelithiasis?

Answer 8

Presence of gallstones in the bile duct.

Question 9

Risk Factors of gallstones (5D).

Answer 9

5Fs :-
1. Fat (Obesity enhances Cholesterol synthesis and secretion).
2. Forty.
3. Female (Oestrogen increases activity of HMG-CoA Reductase and Pregnancy is a risk factor).
4. Fair.
5. Family History.
* Increased levels of cholesterol.
A. Diabetes Mellitus.
B. Crohn’s disease.
C. Rapid Weight Loss e.g. Surgery.
D. Drugs - Fibrates, COCP.

Question 10

Why is Crohn’s disease associated with gallstones? (2)

Answer 10

1. Malabsorption of bile salts from the terminal ileum.
2. Depletion of bile salts so not enough bile to maintain the cholesterol dissolved in bile.

Question 11

What type of anaemias are associated with gallstones?

Answer 11

Haemolytic Anaemias - increased bilirubin production.

Question 12

Features of Biliary Colic (6).

Answer 12

1. Intermittent (Temporary obstruction to the drainage of the gallbladder, getting lodged at the neck of the gallbladder or in the cystic duct and falling back into the gallbladder to resolve symptoms).
2. Severe Colicky Epigastric/RUQ Pain.
3. Triggered by Meals (especially high-fat meals) = postprandial.
4. Lasting between 30 minutes and 8 hours.
5. Associated N&V.
6. Radiates to Right Shoulder/Interscapular Region.

Question 13

Why are high-fat meals associated with biliary colic? (2)

Answer 13

1. Fat entering the digestive system causes CCK (Cholecystokinin) secretion from the duodenum.
2. CCK triggers contraction of the gallbladder = biliary colic.

Question 14

Gallstone LFTs (3).

Answer 14

OBSTRUCTIVE PICTURE :
1. Raised Bilirubin.
2. Raised ALP.
3. Smaller (than ALP) rise in ALT/AST.

Question 15

What is ALP?
Give 4 other causes of raised ALP.

Answer 15

Alkaline Phosphatase - non-specific marker enzyme originating in liver, biliary system and bone; can be raised in pregnancy due to placental production; liver/bone malignancy; PBC/ Paget’s Disease of the Bone.

Question 16

What are ALT and AST?

Answer 16

ALT - Alanine Aminotransferase and AST - Aspartate Aminotransferase - enzymes produced in the liver; markers of hepatocellular injury.

Question 17

ALT and AST Pictures (2).

Answer 17

1. OBSTRUCTIVE Picture : ALT and AST increase slightly but higher rise in ALP.
2. HEPATITIC Picture : ALT and AST are high compared with the ALP level - intrahepatic + hepatocellular injury.

Question 18

Investigations of Gallstones (3).

Answer 18

1. 1st Line - US Scan (limited by patient’s weight, gaseous bowel obstructing view, discomfort from probe).
2. MRCP (if US does not show stones in the duct but there is bile duct dilation or raised bilirubin, suggestive of obstruction).
3. CT Scan - more suitable for other differential diagnoses.

Question 19

What is MRCP?

Answer 19

Magnetic Resonance Cholangio-Pancreatography - an MRI scan that produces a detailed image of the biliary system.

Question 20

What is ERCP?

Answer 20

Endoscopic Retrograde Cholangio-Pancreatography - inserting an endoscope down the oesophagus, past the stomach, to the duodenum and the opening of the common bile duct (Sphincter of Oddi), giving access to the biliary system.

Question 21

What is the main indication for ERCP?

Answer 21

Clear stones in the bile ducts.

Question 22

What can ERCP be used for? (5)

Answer 22

1. Injecting contrast and taking X-rays to visualise the biliary system and diagnose pathology e.g. stones/strictures.
2. Perform a sphincterotomy on the Sphincter of Oddi if it is dysfunctional (blocking flow).
3. Clear stones from the ducts.
4. Insert stents to improve bile duct drainage e.g. with strictures, tumours.
5. Take biopsies of tumours.

Question 23

Give 3 complications of ERCP.

Answer 23

1. Excessive bleeding.
2. Cholangitis (infection in the bile ducts).
3. Pancreatitis.

Question 24

Management of Gallstones.

Answer 24

1. Asymptomatic - Conservative.
2. Symptomatic/Complicated - Cholecystectomy.
3. Frail Patient - US-guided Cholecystectomy.

Question 25

What is a Cholecystectomy? (2)

Answer 25

1. Surgical removal of the gallbladder.
2. Laparoscopic (Right Subcostal ‘Kocher’ Incision > Open Surgery = Less Complications + Faster Recovery.

Question 26

What is a unique complication of a Cholecystectomy?

Answer 26

Post-Cholecystectomy Syndrome : group of non-specific symptoms that can occur after a cholecystectomy, attributed to changes in the bile flow.

Question 27

Give 6 features of Post-Cholecystectomy Syndrome.

Answer 27

1. Diarrhoea.
2. Indigestion.
3. Epigastric/RUQ Pain and Discomfort.
4. Nausea.
5. Intolerance of Fatty Foods.
6. Flatulence.

Question 28

What type of LFT picture does TPN result in?

Answer 28

Obstructive.