Gastroenterology question bank

Gastroenterology

Gastroenterology is the branch of medicine that deals with the study of the digestive system and its disorders. It covers a wide range of medical and surgical procedures, from the evaluation of digestive symptoms, such as abdominal pain and heartburn, to the diagnosis and management of more serious conditions, such as inflammatory bowel disease, liver disease, and digestive tract cancers.

With the increasing incidence of digestive disorders, gastroenterology plays a crucial role in modern medicine and has a significant impact on patient health and well-being. If you are a medical student looking to expand your knowledge of this important field, then why not try our free multiple choice questions? They are an interactive way to test your understanding of gastroenterology and challenge yourself to learn more.

Child pugh scoring system

Which of the following are markers of severity of liver disease as adjudged by the child pugh scoring system?

  • Encephalopathy
  • C-reactive protein
  • Albumin
  • HGC
  • Troponin

Crohn’s vs UC

What are the differences in the histology / macroscopic appearances / clinical features to distinguish between Crohn’s and ulcerative colitis?

Crohn’s: Granulomatous transmural inflammation which can affect any part of the GI tract.

UC: mucosal inflammation which extends from the rectum proximally but “never” past the ileocecal valve.

These are powerful pieces of knowledge. For example if the question was relating to a barium meal to look at the small bowel, or the appearance of small bowel on MRI, you can be confident that if its choice between UC and Crohn’s, its going to be Crohn’s.

Crohn’sUC
Biopsy: GranulomaYesNo
Inflammation extent on BiopsyTransmuralSupertficial
Goblet cells*PresentReduced
Crypy abscessesPresent (small amounts)Present (Large amounts
Involves the rectumSeldomAlways
Skip LesionsYesNo
Involvement of Small bowelYesNo
Fistulae (e.g. colovesical)YesNo
Biliary duct involvementNoYes
Cancer RiskLowerHigher
SmokingCommonerRarer
Raised inflammatory markersYesYes

*Goblet cells are cells shaped like goblets that secrete mucous and have villi that extend into the bowel to assist them in this task. They’re picked off by UC.

Follow up to H pylori

A 35 year old salesman is successfully treated for H Pylori infection following being diagnosed with peptic ulcer disease.

Following a compliant 2 week course of triple eradication therapy what would you expect the results to be?

Although there are some resistant strains, eradication therapy is likely to be successful.

The serology will “stay positive” i.e. you will retain antibodies to H Pylori.
However the otehr objective tests will be negative.

Serology is approx 80% specific. To check eradication common practice is to do a C14 breath test:

Carbon 14 Breath Test for H Pylori
Drink radiolabelled urea
The bacteria metabolise the radiolabelled urea and make radiolabelled CO2 (C14O2)
This can then be detected in the patients breath: i.e. if detected then H Pylori is not eradicated!

Lengths of the small bowel

Order the lengths of the different parts of the small bowel from smallest to largest.

  • jejunum
  • ileum
  • duodenum

Remember, chyme passes from the duodenum to the jejunum to the ileum. The duodenum is shorter than the jejunum which is shorter than the ileum. This constitutes the entirety of the small bowel which is about 20 foot long in total (approximately 6 meters / or about one 16th of a football pitch / a bit over half a tennis court / a few cars).

Hep C needlestick

A medical student sustains a needlestick on an intravenous drug user. Unfortunately this user is HIV positive, Hepatitis C positive and Hepatitis B positive.

Regarding Hepatitis C which of the following statements is true?

  • Vaccination to Hepatitis C is routinely available to healthcare professionals and confers some protection
  • The chance of transmission is high (>30%)
  • If transmitted the disease may preclude the clinician from partaking in certain medical career routes
  • Hepatitis C if transmitted has a high chance of cure.
  • None of the listed answers are correct

The chance of transmission is high (>30%)

The chances of transmission are as follows

HIV/AIDS 0.3%
Hep B 3%
Hep C 33%

The rule of 3’s.

Hep C is the most transmissible of all 3 conditions. As a healthcare professional with a transmittable disease it may preclude you from working in certain specialities e.g. some surgical specialities.

Asterixis

Which of the following cause asterixis?

Please choose 2 answers:

  • Crohn’s Disease
  • Irritable Bowel syndrome
  • CO2 retention
  • Wilsons Disease
  • Alcohol related liver disease
  • Ulcerative Colitis
  • Chronic obstructive pulmonary disease
  • Motor Neuron Disease
  • Coeliac Disease

Wilsons Disease
Alcohol related liver disease

Asterixis is also called the “liver flap”: an asymmetrical “flapping of the hands when the arms are help extended with the wrists dorsiflexed: it’s a poor prognostic sign.

As such the question could read:

“which of the following are associated with decompensated/chronic liver disease”

The 2 best answers would be ‘alcohol related liver disease’ and ‘Wilson’s disease’.

It is said to be asymetrical when compared to the flap of CO2 retention.

B12 absorption

A patient with Crohn’s disease has her terminal ileum resected.
Which of the following substances would you specifically expect her to develop a deficiency of as a result of her surgery?

  • Vitamin B12
  • Iron
  • Vitamin D
  • Vitamin A
  • Fat

Vitamin B12

B12 and bile salts are the 2 substances specificaly absorbed in the terminal ileum. Remember to absorb B12 you also need intrinsic factor from the gastric parietal cells in the stomach.

Causes of Chronic liver disease

What is the commonest cause of chronic liver disease in the United Kingdom?

  • Paracetamol Overdose
  • Alcohol Related Liver disease
  • Hepatitis B
  • Hepatitis C
  • Autoimmune liver disease

Alcohol Related Liver disease
Although only approximately 10% of People who abuse alcohol will develop cirrhosis they still form the largest group of patients who develop chronic liver disease.

Anaemic woman case

A healthy 22 year old woman is incidentally found to be anaemic on an insurance medical. She has absolutely no GI symptoms. Blood tests show the following.

Hb 9.6 (11.5-14)
MCV 97 (80-99)
B12 110 (>150)
Ferritin 4 (>10)
Coeliac screen (TTG antibody) – negative
Immunoglobulins:
IgA A low
IgG normal
IgM normal

Which of the following is true?

  • She is suffering from malabsorption
  • Her abnormalities most likely relate to GI blood loss
  • Her Abnormalities most likely relate to a combination of GI blood loss and menorrhagia
  • She has pernicious anaemia
  • She is likely to have a combination of gastritis/ peptic ulcer disease

She is suffering from malabsorption

She has a combined iron and B12 deficiency. This suggests malabsorption. Pernicious anaemia is an autoimmune condition characterised by malabsorption of B12 selectively. The low ferritin is an excellent marker of iron deficiency. The combination of iron and B12 deficiency suggests small bowel disease.

In the above patient what is the most likely disease causing her symptoms?

  • Coeliac disease
  • Crohn’s disease
  • Ulcerative colitis
  • Alcoholic liver disease
  • Viral Hepatitis

In the absence of symptoms a diagnosis of inflammatory bowel disease causing an anaemia and iron deficiency would be very unlikely. Although her TTG antibody is negative, note the low IgA. Low levels of this immunoglobulin make a TTG test unreliable.

This is a classic MCQ question.

Conjugated and unconjugated bilirubin

In prehepatic jaundice serum bilirubin measured on a standard Liver function test is characteristically:

  • Normal
  • Low
  • “Unconjugated” and normal
  • “Unconjugated” and high
  • “Conjugated” and high

“Unconjugated” and high

Bilirubin is formed from the breakdown of haem from red blood cells. It’s conjugated in the liver by hepatocytes (UDP glucuronlytransferase). “Bilirubin” measured on standard LFT’s does not distinguish between conjugated and unconjugated. In prehepatic jaundice (e.g. G6PD deficiency) the bilirubin will be unconjugated as the liver struggles to cope with the increased load of bilirubin.

Regarding a needlestick to a healthcare professional from a “high risk ” patient (e.g. intra-venous drug user).

Regarding consent for taking blood from the patient to test for HIV/ HepB and Hep C

  • Testing will take >1week to complete.
  • Consent is not specifically needed from the patient for the blood tests following the incident.
  • If the patient does not give consent to viral testing then confidential tests can be done on the patients’ serum from previously stored samples, if available. The patient will then not be told of the result.
  • Testing cannot be carried unless the patient gives informed consent.
  • Testing will not alter the management of the needlestick injury.

Testing cannot be carried unless the patient gives informed consent

Remember you can’t test a patient for any illness unless you have their consent. This applies in theory to any test. It’s particularly important for conditions that may affect life expectancy/fitness to work etc like HIV.

It will affect the treatment. For example if the patient was HIV positive: you would elect to offer the healthcare professions HAART [highly active anti retroviral therapy].

If the patient tested negative, they are likely to be HIV negative. This does not rule out HIV however the transmission risk of an “undetectable” viral load is likely to be minimal.

Diagnosis of UC

From the following what is the investigation of choice for the diagnosis of ulcerative colitis?

  • CT abdomen
  • MRI Abdomen
  • Barium meal & follow through
  • Colonoscopy
  • Capsular endoscopy

Colonoscopy

The answer here is simple: colonoscopy. The histological features of UC are the key to making the diagnosis. A colonoscopy not only gives a view of the characteristic ulceration and inflammation extending distally from the anus (may be microscopic only). Remember during a colonoscopy you can take biopsies of any of the suspicious lesions.

Although the answer does not mention a biopsy the macroscopic appearances would still be more useful at this diagnostic stage and therefore it is the “best” answer.

Fat soluble vitamins

Which of the following is not a fat soluble vitamin?

  • Vitamin A
  • Vitamin B
  • Vitamin D
  • Vitamin E
  • Vitamin K

Vitamin B

Another thing you have to “know”.

Fat soluble vitamins are “ADEK”.

So if you have panceratic exocrine failure / a biliary cause of fat malabsorbtion you are likely to become deficient in those vitamins and therefore become vitamin deficient.

Hep B immunity

What is the best method of ensuring adequate protection against hepatitis B in individuals (e.g. doctors) immunised against the virus?

  • Measurement of Hep B surface antibody level
  • Measurement of Hep B surface antigen level
  • lnitial vaccination course x 3 followed by single 5 year booster
  • lnitial vaccination course x 3 followed by repeated 5 year booster
  • Initial Vaccination course x3 is sufficient

Measurement of Hep B surface antibody level

The initial vaccination course x3 should be followed by a (one off) 5 year booster jab. However this does not ensure adequate immunity: to check a vaccinated person has responded you need to check their antibody titres.

Hepatitis B immunity is best measure by checking HepB Surface Antigen antibodies (HepB S Ab). Levels of >100mlU/ml are thought of as adequate protection.

It is currently advocated that if you receive a needlestick from a Hep B positive patient that you receive a booster vaccine.

Helicobacter pylori

Which of the following is NOT true about Helicobacter pylori?

  • Its treatment consists of combination antibiotics.
  • It is a bacteria
  • Testing includes biopsy, serology and carbon breath test.
  • Its role in the predisposition towards peptic ulcer disease was not formulated until the 1990’s
  • Roughly 20% of people colonised with H pylori will develop peptic ulcer disease

Its treatment consists of combination antibiotics.

Hpylori’s role in peptic ulcer disease wasn’t known until the 1990’s.

Everyone with peptic ulcer disease at endoscopy should have an Hpylori test. The most reliable test is a biopsy (culture and histology) along with the rapid urease test which will give a colour indication if the patient has Hpylori infection.

Triple therapy is whats required
i.e. Combination antibiotics but with the addition of a PPI.e.g. amocycillin/clarithromycin/lansoprazole 2 weeks.

Diagnose this anaemic case

A healthy 31 year old woman is incidentally found to be anaemic on an insurance medical. She has absolutely no GI symptoms, Blood tests show the following.

Hb 9.6(13-18 g/dl)
MCV 77(80-99 fL)
Plt 276(150-300 x109/l)
WCC 6.2(4-10 x109/l)
Ferritin 4>10
CRP 76(<4)
TTG antibody negative

She has a painful rash that she describes as bruises on her legs.

What is the most likely diagnosis?

  • Coeliac disease
  • Inflammatory Bowel disease
  • Wilson’s disease
  • Primary biliary sclerosis
  • Viral Hepatitis

Inflammatory Bowel disease

Yes that’s erythema nodosum occurring in a slightly unusual area: painful red lump associated with IBD. Bloods show classical iron deficiency with elevated inflammatory markers.

IBS

Regarding Irritable bowel syndrome:

  • The C reactive protein is characteristically elevated
  • Duodenal biopsy may show villous atrophy
  • Sigmoidoscopy may reveal skip lesion ulceration
  • Mesalazine is used to control disease activity
  • None of the listed answers are correct

None of the listed answers are correct

IBS is characterised by normal test results. Therefore a high CRP, villous atrophy and ulceration would all point towards other diseases. Antispasmodics can provide relief along with probiotics such as Yakult (TM). Mesalazine is a 5ASA compound used to treat inflammatory bowel disease.

Chronic abdominal pain diagnosis

A 45 year old salesman has chronic abdominal pain for the past 6 years worse over the past 1year. He has not lost weight. He opens his bowels between 2 and 3 times a day. He passes large volumes of mucus in his stool. He describes tenesmus,

His investigations show the following:

Hb  15.2 (13-18 g/dl)
MCV  82  (80-99 fL)
Plt  196  (150-300 x109/l)
WCC  6.1 (4-10 x109/l)
Na138(135-145mmol/l)
K4.2(3.5-5.1mmol/l)
U4.1(4-9mmol/l)
Creatinine77(60-100 micromols/l)
CRP7(<5mg/l)
Albumin42(35-45g/l)
Alk Phos83(<110iu/l)
ALT22(<40 iu/l)
Bilirubin11(<20 micromols/l)
GGT 20(0-70)

INR  1.0

Glucose4.1 mmol/l
Amylase 23(<90)
CK143(<150 iu/l)
ESR6

What is the most likely diagnosis?

  • Crohn’s Disease
  • Ulcerative colitis
  • Coeliac disease
  • Irritable bowel syndrome
  • Thyrotoxicosis

Irritable bowel syndrome

Whilst all of the above could have some features of his presentation there are some clues. Tenesmus is the feeling of a continuous desire to pass stool. It’s associated with a number of things including IBS. The slightly high CRP at 7 is non specific and does not suggest a diagnosis of inflammatory bowel disease. Coeliac disease can cause cramps, bloating and diarrhoea but the absence of weight loss and excessive mucus is against that.

IBS remains a diagnosis of exclusion: you must always consider other explanations e.g. colorectal cancer etc.

Markers that would go against diagnosis are:

Age>40

Weight loss

Nocturnal symptoms (diarrhoea)

Mouth ulcers

Blood PR (not mucous)

Abnormal investigations (e.g. anaemia, raised inflammatory markers)

Clinical pearl: Nocturnal diarrhoea is has a high chance of being pathological: think IBD / infection / cancer etc.

Needlestick Hep B

A medical student sustains a needlestick on an intravenous drug user. Unfortunately this user is HIV positive, Hepatitis C positive and Hepatitis B positive.

With regards to hepatits B, which of the following is true?

  • In an unvaccinated person, the chance of transmission is reasonably high (1-10%)
  • The chance of transmission is likely to be low (<1%)
  • The chance of transmission is very high (>30%)
  • Repeated Hepatitis B vaccination with adequate antibody levels completely protects against transmission to the medical student
  • If transmitted, Hepatitis B is treatable but incurable

In an unvaccinated person, the chance of transmisison is reasonably high (1-10%)

All Doctors working in a risk area are required to be vaccinated against hepatitis B. The vaccination will confer protection against the transmission of hepatitis B.

The current regime is 3 vaccines of hep B surface antigen: the immune system will then “recognise” hepatitis B.

Needlestick HIV

A medical student sustains a needlestick on an intravenous drug user. Unfortunately this user is HIV positive, Hepatitis C positive and Hepatitis B positive.

With regards to if the transmission of HIV, which of the following is true?

  • Post exposure prophylaxis is not recommended
  • The chance of transmission is likely to be low (<1%)
  • The chance of transmission is reasonably high (>20%)
  • The infectious risk is unrelated to the patients HIV viral load
  • To date there have been no reported case of HIV transmission in the literature from these events

The chance of transmission is likely to be low (<1%)

Post exposure prophylaxis is reccomended.

You can get an HIV test for a patient in <2 hours if you are uncertain to if they have HIV.
The risk of transmission is related to the viral load that the patient has (copies of the virus /ml of blood).

Asymptomatic jaundice diagnosis

An obese 47 year old presents with asymptomatic jaundice. Examination of her abdomen reveals a palpable gall bladder. There’s extensive pruritis.

Her blood results are as follows

Albumin 32
Alk Phos 456 (<110)
ALT 88 (<40)
Bilirubin 120(<20)
INR 1.6
GGT 400 (0-70)

What’s the most likely diagnosis?

  • Alcoholic Hepatitis
  • Paracetamol Overdose
  • Gallstones
  • Pancreatic cancer
  • Primary billiary cirrhosis

Pancreatic cancer

No marks for anything other than this: the famous Courvoisier’s law:

In the presence of a palpable Gallbladder (GB) in painless jaundice the diagnosis is unlikely to be gallstones.

Why?

Gallstones cause chronic GB fibrosis. A distended GB suggests a more acute obstruction

Why not PBC or alcohol?

The LFT’s are an “obstructive picture (high Alk P/ GGT/ Bili reasonably low ALT). Alcohol would not do this or give the distended GB. PBC could give the obstructive picture but you’d be less likely to find the palpable GB.

Synthetic liver function

Which of the following blood tests is the most accurate marker of acute synthetic liver function?

  • Albumin
  • Alkaline Phosphatase
  • INR
  • ESR
  • Bilirubin

INR

Clotting factors synthesised by the liver have a very short T1/2 (<24 hours). As such in acute liver injury, the INR is the most important prognostic marker of acute synthetic liver function.

In acute liver failure the INR will become elevated, however substances with a longer T1/2 (e.g. albumin has a half life of approximately 21 days)

This applies to many forms of acute liver injury:

E.g. in paracetamol overdose the most important marker is INR, not ALT etc

In acute viral hepatitis a prolonged INR is more important than an ALT of 4000- although the ALT is a marker of hepatocellular injury, it is not as powerful a marker of synthetic function.

Hep B Hepatocellular cancer

Regarding this statement:
“Hepatitis B vaccine is a vaccine that reduces the risk of malignancy”

  • True
  • False

True: Hep B infection leads to a vastly increased risk of hepatocellular cancer.

The Centre for disease Control in Atlanta recognised hepatitis B vaccine to be the first “anti cancer vaccine”.

You can read more on the CDC vaccines pages by following the link here: https://www.cdc.gov/vaccines/