Gastroenterology

Question 1

Causes of increased ALP

Answer 1

Increased in bile duct obstruction

Question 2

What is ALP and where is it distributed in the body

Answer 2

Alkaline Phosphatase

High levels in cell membranes of:
- Biliary tree
- intestine
- placenta
- bone
- renal tubular cells

“Plate of Liver and Kidney beans”

(N.B. low levels in liver)

Question 3

Hepatitis picture of LFTs

Answer 3

High transaminases (AST / ALT) with proportionally less of a rise in ALP

Question 4

Criteria for Acute Liver failure

Answer 4

1. Increase in PT (by 4-6 seconds) - INR >1.5
2. Development of hepatic encephalopathy
3. WITHOUT pre-existing cirrhosis & illness for > 6 months

Question 5

What is GGT

Answer 5

Gamma-glutamyl transpeptidase

Enzyme found around body but particularly in the liver (primarily biliary epithelium)

Increased in bile duct obstruction

Question 6

Causes of metabolic alkalosis

Answer 6

Vomiting / aspiration
Diuretics
Hypokalaemia
Primary hyperaldosteronism (Conn’s syndrome)
Cushing’s syndrome

Question 7

Biochem disturbance from prolonged vomiting

Answer 7

Metabolic alkalosis + hypokalaemia

Question 8

Why does vomiting cause hypokalaemia and metabolic acidosis?

Answer 8

Large amounts of hydrochloric acid are lost –> loss of H+ ions and fluid

Fluid loss –> activation of the renin-angiotensin-aldosterone system (RAAS) due to reduced renal perfusion –> increased aldosterone secretion.

Aldosterone promotes the reabsorption of Na+ in exchange for H+ and K+ in the kidneys.

In general, where Na+ goes, water follows, meaning the blood volume is increased, however, more potassium and H+ are lost, leading to hypokalaemic metabolic alkalosis

Question 9

Prolonged diarrhoea ABG

Answer 9

hypokalaemia
hypovolaemic shock
metabolic acidosis (due to the loss of bicarbonate ions from the gut)

Question 10

What is Primary sclerosing cholangitis?

Answer 10

biliary disease of unknown aetiology characterised by inflammation and fibrosis of intra and extra-hepatic bile ducts

Question 11

What condition is primary sclerosing cholangitis associated with ?

Answer 11

Ulcerative colitis

8% of people with UC have PSC
80% of people with PSC have UC

(also Crohns and HIV but a lot less common)

Question 12

What is primary sclerosing cholangitis?

Answer 12

intrahepatic or extrahepatic ducts become strictured and fibrotic

Question 13

Hepatic consequence of primary sclerosing cholangitis

Answer 13

Chronic bile obstruction eventually leads to liver inflammation (hepatitis), fibrosis and cirrhosis.

Question 14

Presentation of Primary sclerosing cholangitis

Answer 14

Jaundice
Chronic right upper quadrant pain
Pruritus
Fatigue
Hepatomegaly
Signs of cirrhosis if they have developed this

Question 15

LFTs “cholestatic picture”

Answer 15

ALP = most derranged LFT and may be the only abnormality at first

May be a rise in bilirubin as strictures become more severe and prevents bilirubin from being excreted through the bile duct

Other LFTs (i.e. transaminases: ALT and AST) can also be deranged, particularly as the disease progresses to hepatitis.

Question 16

Role of autoantibodies in primary sclerosing cholangitis

Answer 16

Not helpful in diagnosis (Not specific/sensitive)

Can indicate where there is autoimmune element –> may respond to immunosuppression

• p-ANCA - in up to 94%
• Antinuclear antibodies (ANA) - in up to 77%
• Anticardiolipin antibodies (aCL) in up to 63%

Question 17

What is an MRCP and what is it used for?

Answer 17

MRI of Liver, bile ducts and pancreas

Diagnosis of:
- PSC
-

Question 18

Fat soluble vitamins

Answer 18

Vitamins A, D, E, and K

(Amelia Doesnt Even Know)

Question 19

Management of primary sclerosing cholangitis

Answer 19

1. Only definitive = liver transplant
2. ERCP - stents to open strictures
3. Ursodeoxycholic acid - may slow progression of disease
4. Colestyramine - bile acid sequestrate in that it binds to bile acids to prevent absorption in the gut and can help with pruritus due to raised bile acids

Question 20

Where foes ECRP scope pass through from GI tract –> biliary system

Answer 20

sphincter of Oddi and into the ampulla of Vater

Question 21

“Beads on a string” appearance of bile ducts

Answer 21

Primary sclerosing cholangitis

Question 22

What is Primary Biliary Cirrhosis?

Answer 22

Chronic, progressive, autoimmune condition leading to destruction of intrahepatic ducts

The first parts to be affected are the intralobar ducts, also known as the Canals of Hering. This causes obstruction of the outflow of bile, which is called cholestasis. The back-pressure of the bile obstruction and the overall disease process ultimately leads to fibrosis, cirrhosis and liver failure.

Question 23

Which conditon is autoimmune out of PBC and PSC ?

Answer 23

Primary Biliary Cirrhosis

Question 24

Conditions associated with Primary Biliary Cirrhosis?

Answer 24

Coeliac disease
Thyroiditis
Middle aged women
Rheumatoid conditions (e.g. systemic sclerosis, Sjogrens and rheumatoid arthritis)

Question 25

Autoantibodies associated with primary biliary cirrhosis?

Answer 25

Anti-mitochondrial antibodies - most specific to PBC, part of the diagnostic criteria) Anti-nuclear antibodies (35% of patients)

Question 26

Ursodeoxycholic acid role

Answer 26

used in the management and treatment of cholestatic liver disease

Question 27

Treatment of primary biliary cirrhosis

Answer 27

Ursodeoxycholic acid (better response to this compared to PSC) Colestyramine - symptomatic management of itching Immunosuppresants (some patients)

Question 28

What is aminosalicylates (e.g. mesalazine) used for?

Answer 28

To control inflammation in GI tract Used in Ulcerative colitis I) Inducing remission in mild to moderate disease II) Maintaining remission

Question 29

Treatment of Severe flare of UC

Answer 29

Admit + IV hydrocortisone

Question 30

Treatment of flare of Crohns

Answer 30

Steroids (e.g. oral prednisolone or IV hydrocortisone) If steroids don't help, consider immunosuppression: Azathioprine Methotrexate

Question 31

Effect of smoking on IBD ?

Answer 31

Crohns - smoking increases risk UC - smoking decreases risk

Question 31

Effect of smoking on IBD ?

Answer 31

Crohns - smoking increases risk UC - smoking decreases risk

Question 32

Severe disease criteria IBD

Answer 32

if >= 6 bowel movments per day PLUS at least 1 feature of systemic upset Other features: Blood in stool clearly visible Pyrexia HR >90 bpm Anaemia ESR >30 (Trulove & Witts' criteria)

Question 33

Which IBD has tenesmus

Answer 33

UC

Question 34

Rome IV criteria for IBS

Answer 34

Recurrent abdo pain at least one day/week over the past three months (with symptom onset at least six months ago) and two of the following: 1. It is related to defecation and/or 2. it is associated with a change in stool frequency, and/or 3. It is associated with a change in stool appearance.

Question 35

What is Charcot's triad?

Answer 35

Suggestive of ascending cholangitis (bacterial infection of the biliary tree - typically E.Coli) 1. Fever 2. Jaundice 3. Right upper quadrant pain

Question 36

What is Reynold's pentad?

Answer 36

Suggestive of severe ascending cholangitis = Charcot's triad + hypotension and confusion SO 1. Fever 2. Jaundice 3. Right upper quadrant pain 4. Hypotension 5. Confusion

Question 37

Management of ascending cholangitis

Answer 37

1. IV antibiotics 2. ERCP after 24-48 hours to relieve any obstruction

Question 38

Key differentiating features between chronic liver disease and acute failure

Answer 38

In acute but not chronic - Prothombin time raised - Very high bilirubin - presence of encephalopathy

Question 39

Causes of acute liver failure

Answer 39

Paracetamol overdose Alcohol Viral hepatitis (A & B) Acute fatty liver of pregnancy

Question 40

Pancreatitis scoring system

Answer 40

P - PaO2 <8kPa A - Age >55-years-old N - Neutrophilia: WCC >15x10(9)/L C - Calcium <2 mmol/L R - Renal function: Urea >16 mmol/L E - Enzymes: LDH >600iu/L; AST >200iu/L A - Albumin <32g/L (serum) S - Sugar: blood glucose >10 mmol/L