Gastroenterology

Question 1

First line pharmacological management for primary biliary cholangitis?

Answer 1

Ursodeoxycholic acid -
slows disease progression and improves symptoms

Question 2

Main cause of anal cancer?

Answer 2

HPV infection is the strongest risk factor for anal cancer.

Anal intercourse and a high lifetime number of sexual partners increases the risk of HPV infection.

Question 3

Antibody for primary biliary cholangitis?

Answer 3

Anti-mitochondrial antibodies (AMA) M2 subtype are present in 98% of patients and are highly specific.

Question 4

First line treatment for C.Diff infection?

Answer 4

First episode of C. difficile infection:
- First-line is oral vancomycin for 10 days.
- Second-line therapy: oral fidaxomicin.

Question 5

Antibiotic choice in life threatening C.Diff infection?

Answer 5

Oral Vancomycin and IV Metronidazole.

Question 6

Most common site of pathology for ischaemic colitis?

Answer 6

The splenic flexure is the most commonly affected site in ischaemic colitis, which is a watershed area where the blood supplies of the inferior mesenteric artery and superior mesenteric artery change.

‘Thumbprinting’ may be seen on abdominal x-ray due to mucosal oedema/haemorrhage.

Question 7

Most common organism in ascitic fluid culture in SBP?

Answer 7

Spontaneous bacterial peritonitis: most common organism found on ascitic fluid culture is E. coli.

Question 8

Treatment of choice in small bowel bacterial overgrowth syndrome?

Answer 8

Rifaximin is now the treatment of choice due to relatively low resistance. Co-amoxiclav or metronidazole are also effective in the majority of patients.

Question 9

Second line therapy for C.diff infection?

Answer 9

Oral fidaxomicin.

Question 10

Most useful screening test for hereditary haemochromatosis?

Answer 10

Transferrin saturation is considered the most useful marker.

Ferritin should also be measured but is not usually abnormal in the early stages of iron accumulation.

Testing family members =
genetic testing for HFE mutation

Question 11

Antibody for autoimmune hepatitis?

Answer 11

Smooth muscle antibodies

Question 12

Causes for acute pancreatitis?

Answer 12

• Gallstones
• Ethanol
• Trauma
• Steroids
• Mumps (other viruses include Coxsackie B)
• Autoimmune (e.g. polyarteritis nodosa), Ascaris infection
• Scorpion venom
• Hypertriglyceridaemia, Hyperchylomicronaemia, Hypercalcaemia, Hypothermia
• ERCP
• Drugs (azathioprine, mesalazine*, didanosine, bendroflumethiazide, furosemide, pentamidine, steroids, sodium valproate)

Question 13

Commonest cause of HCC in UK and Worldwide?

Answer 13

• Hepatitis C most common cause in Europe and UK. The virus causes chronic inflammation leading to cirrhosis, which predisposes to the development of HCC.
• Hepatitis B most common cause worldwide.

Question 14

Electrolyte imbalance seen in refeeding syndrome?

Answer 14

Hypophosphataemia, hypokalaemia and hypomagnesaemia are the characteristic electrolyte disturbances seen in patients with refeeding syndrome.

Question 15

Investigation for Zollinger-Ellison Syndrome?

Answer 15

• Fasting gastrin levels: the single best screen test
• secretin stimulation test

Zollinger-Ellison syndrome is condition characterised by excessive levels of gastrin, usually from a gastrin secreting tumour usually of the duodenum or pancreas. Around 30% occur as part of MEN type I syndrome.

• Multiple gastroduodenal ulcers
• Diarrhoea
• Malabsorption

Question 16

Mode of inheritance for Peutz-Jeghers syndrome?

Answer 16

Peutz-Jeghers syndrome is an autosomal dominant condition characterised by numerous hamartomatous polyps in the gastrointestinal tract. It is also associated with pigmented freckles on the lips, face, palms and soles.

• Hamartomatous polyps in the gastronintestinal tract (mainly small bowel). Small bowel obstruction is a common presenting complaint, often due to intussusception,
  gastrointestinal bleeding.
• Pigmented lesions on lips, oral mucosa, face, palms and soles

Question 17

Diagnostic investigation for chronic pancreatitis?

Answer 17

CT pancreas is the preferred diagnostic test for chronic pancreatitis - looking for pancreatic calcification.

Question 18

Drug choice for prophylaxis of variceal bleeding?

Answer 18

Propranolol -
reduced rebleeding and mortality compared to placebo

Question 19

Which cell secretes the hormone Gastrin?

Answer 19

Gastrin hormone is secreted from the G cells in the antrum of the stomach and increases acid secretion from gastric parietal cells.

Question 20

Which cells secrete somatostatin?

Answer 20

Somatostatin is secreted by D cells in the pancreas and stomach and is stimulated by fat, bile salts and glucose in the intestinal lumen. It acts to decrease acid, pepsin and pancreatic enzyme secretion.

Question 21

What is the first line management for alcoholic hepatitis?

Answer 21

Prednisolone is often used during acute episodes of alcoholic hepatitis.

Maddrey’s discriminant function (DF) is often used during acute episodes to determine who would benefit from glucocorticoid therapy.

it is calculated by a formula using prothrombin time and bilirubin concentration.

Question 22

Most common affected site in UC?

Answer 22

Rectum.

The rectum is the most commonly affected site in UC, with inflammation usually starting at the rectum and extending proximally in a continuous manner throughout the colon. In some cases, it may involve only the rectum (proctitis) or extend to involve other parts of the colon.

Question 23

Management for life threatening C.Diff infection?

Answer 23

Oral vancomycin AND IV Metronidazole.

Question 24

How to diagnose SBP and most common organism?

Answer 24

The diagnosis of SBP is made when the neutrophil count in the ascitic fluid is greater than 250 cells/ul.

The most common organism found on ascitic fluid culture is E. coli.

Question 25

Abx choice for SBP?

Answer 25

IV Cefotaxime.

Question 26

Which Cells secrete which GI hormone?

Answer 26

G cells secrete Gastrin.

S cells secrete secretin.

I cells secrete CCK.

D cells secrete somatostatin.

Question 27

First line investigations for Coeliac disease?

Answer 27

• Tissue transglutaminase (TTG) antibodies (IgA) are first-choice.
• Endomyseal antibody (IgA)
  needed to look for selective IgA deficiency, which would give a false negative coeliac result.

Anti-casein antibodies are also found in some patients

• Endoscopic intestinal biopsy
  the ‘gold standard’ for diagnosis - this should be performed in all patients with suspected coeliac disease to confirm or exclude the diagnosis.

Traditionally done in the duodenum but jejunal biopsies are also sometimes performed.

• Findings supportive of coeliac disease:
  villous atrophy
  crypt hyperplasia
  increase in intraepithelial lymphocytes
  lamina propria infiltration with lymphocytes

Question 28

First line test for small bowel overgrowth syndrome?

Answer 28

Hydrogen breath test.

The large amounts of bacteria in the small bowel compete with the patients gut for nutrients. In the hydrogen beath teat, the patient is fasted and then given a glucose drink. Bacteria will metabolise the glucose and produce hydrogen compounds which are then measured in the breath. A significant rise in hydrogen compounds from baseline indicates small bowel overgrowth syndrome.

Question 29

GOLD standard test for GORD?

Answer 29

24hr oesophageal pH monitoring. This investigation is considered the gold standard for diagnosing gastro-oesophageal reflux disease (GORD) because it allows for the direct measurement of acid exposure in the oesophagus over a 24-hour period. It provides quantitative data on the frequency and duration of acid reflux episodes, including those that do not cause symptoms, thus offering a highly sensitive and specific test for GORD.

Question 30

Mode of inheritance for Familial Adenomatous Polyposis (FAP)?

Answer 30

Autosomal dominant.

Familial adenomatous polyposis (FAP) is an autosomal dominant disorder, which means that it only requires one copy of the mutated gene from either parent to be passed on for the offspring to develop the condition. This mode of inheritance results in a 50% chance of each child inheriting the disorder if one parent carries the mutation. The APC gene located on chromosome 5 is responsible for FAP and mutations in this gene lead to uncontrolled growth of cells in the colon, resulting in polyp formation.

Question 31

What is the H.Pylori eradication regime?

Answer 31

Eradication may be achieved with a 7-day course of:
- PPI + Amoxicillin + (Clarithromycin OR Metronidazole)

• if penicillin-allergic: PPI + Metronidazole + Clarithromycin

Question 32

Management for eosinophilic oesophagitis?

Answer 32

Eosinophilic oesophagitis is characterised by an allergic inflammation of the oesophagus. An oesophageal biopsy will show dense infiltrate of eosinophils in the epithelium.

• Dietary modification: This is both effective in adults and children. There are three methods available to begin excluding food from the diet. The elemental diet (involves taking an amino acid mixture for six weeks), exclusion of six food groups (involves avoiding foods commonly associated with allergy e.g. nuts, soy, egg, seafood), and the targeted elimination diet (involves excluding foods that have been identified as allergy-triggering during allergy testing). It is important to involve a dietitian when attempting to modify diet.

Topical steroids e.g. fluticasone and budesonide are options when dietary modification fails. This requires the patient to swallow solutions of the steroid to line the oesophagus. This should be done for eight weeks before being reassessed.

Oesophageal dilatation: 56% of patients require this at some point in their treatment to reduce the symptoms associated with oesophageal strictures

Question 33

Diagnostic imaging for pancreatic cancer?

Answer 33

High-resolution CT scanning is the diagnostic investigation of choice for pancreatic cancer.

Question 34

First line investigation for ascending cholangitis?

Answer 34

Ultrasound is generally used first-line in suspected cases to look for bile duct dilation and bile duct stones.

Mx:
- Intravenous antibiotics
- Endoscopic retrograde cholangiopancreatography (ERCP) after 24-48 hours to relieve any obstruction.

Question 35

Which cells produce CCK?

Answer 35

cholecystokinin (CCK) from the I cells of the duodenum.

CCK promotes gallbladder contractility, causing the release of bile into the small intestine to aid with lipid emulsification.