Gastrointestinal Flashcards
Define inflammatory bowel disease
Umbrella term for two main diseases causing inflammation of the GI tract:
- Ulcerative Colitis
- Crohn’s disease
They both involve inflammation of the walls of the GI tract and are associated with periods of remission and exacerbation.
Dermatological manifestation:
Erythema nodosum - related to active disease
Pyoderma gangrenosum - not related to disease acitivity
What are the features of Crohn’s disease?
NESTS
N - no blood or mucus
E - entire GI tract
S – “Skip lesions” on endoscopy.
T – Terminal ileum most affected and Transmural (all 4 layers) inflammation
S – Smoking is a risk factor (don’t set the nest on fire)
Crohn’s is also associated with weight loss, strictures and fistulas.
What is the aetiology of Crohn’s?
Still unclear, but genetic links have been found - particularly mutations in the NOD2 pathogen recognition proteins
Environmental factors possibly include smoking, oral contraceptive pill, poor diet, NSAIDs, exposure to antibiotics etc.
What is the pathophysiology of Crohn’s?
Thought to occur in genetically and immunologically susceptible individual.
- Initial inflammatory infiltrate enter into intestinal crypts
- This develops into ulceration of the superficial mucosa
- Ulceration penetrates deeper and forms non-caseating granulomas through all layers
What are the risk factors for Crohn’s disease?
- Jewish
- Affects females more than males
- Presentation mostly at 20-40 years
- Lower incidence than UC
What signs and symptoms might a patient with Crohn’s disease present with?
- Abdominal pain (right lower quadrant)
- Prolonged diarrhoea (no blood/intermittent blood and mucus)
- Weight loss
- Perianal lesions
- Fatigue
- Fever
What investigations/tests would you carry out for a patient with suspected Crohn’s disease?
- FBC - anaemia, leukocytosis
- B12 and folate deficiency
- Faecal calprotectin (released by the intestines when inflamed) - does not differentiate between CD or UC
- GOLD STANDARD:
Colonoscopy with ileoscopy and tissue biopsy is diagnostic - granulomatous transmural inflammation - C-reactive protein (CRP) indicates inflammation and active Crohn’s disease
- Stool sample - rule out C.difficile infection.
- Imaging with ultrasound, CT and MRI to detect fistulas, abscesses and strictures
What is the treatment/management for Crohn’s disease on first presentation or during a flare?
Firsr line: oral prednisolone which is a glucocorticoid steroid
If not effective, consider adding immunosuppressant meds such as Azathioprine and Mercaptopurine
What is the treatment/management for Crohn’s disease to maintain remission?
Talk to the patient, as it is reasonable not to take medication when the patient is well.
Otherwise azathioprine or mercaptopurine for maintenance treatment
When is surgery considered for a patient with Crohn’s disease?
When the disease only affects the distal ileum it is possible to resect this area and prevent further disease flares surgically.
However, Crohns typically involves the entire GI tract
Surgery can also be used to treat strictures and fistulas secondary to Crohn’s disease.
What are the possible complications of Crohn’s disease?
Fistulas, strictures (narrowing of intestine0, abscesses and small bowel obstruction
Oral prednisolone - glucocorticoid steroid
Describe:
1) Use
2) Mechanism of action
3) Main side effects
1) Crohn’s disease - first presentation or flare-up
2) Prednisolone exerts glucocorticoid effects with minimal mineralocorticoid effects
3) Increased appetite, mood swings, Cushing’s syndrome
What are the features of ulcerative colitis (UC)?
UC = CLOSEUP
C – Continuous inflammation
L – Limited to colon and rectum
O – Only superficial mucosa affected
S – Smoking is protective
E – Excrete blood and mucus
U – Use aminosalicylates (e.g. mesalazine)
P – Primary Sclerosing Cholangitis (inflammation of bile ducts)
What is the aetiology of UC?
Recognised as a multifactorial polygenic disease as exact aetiology is still unknown
Theories indicate that genetically susceptible individuals might develop UC in response to environmental triggers.
Likely an autoimmune disease initiated by an inflammatory response to colonic bacteria
What is the pathophysiology of UC?
Macroscopically:
- Limited to the colons and rectum.
- Starts at the rectum, and can progress as far as the ileocaecal valve (junction between small and large intestine)
- Continuous inflammation – no skip lesions (as in CD)
- Ulcers & pseudo-polyps in severe disease
Microscopically:
- superficial mucosa inflamed – no deeper (not transmural)
- Crypt abscesses
- Depleted goblet cells
What are the risk factors for UC?
- Jewish
- Affects males & females equally
- Presentation mostly at 20-40 years
- Higher incidence than Crohn’s
- Smoking protective against UC
What signs and symptoms might a patient with UC present with?
- Abdominal pain (lower left quadrant)
- Rectal bleeding
- Diarrhoea
- Blood in stool
- Arthritis and spondylitis
- Malnutrition
- Abdominal tenderness
What are the risk factors for UC?
- Family history of inflammatory bowel disease
- Human leukocyte antigen-B27 (suggestive of autoimmune disease)
- Non-steroidal anti-inflammatory drugs (NSAIDs)
What investigations/tests would you carry out for a patient with UC?
- GOLD STANDARD!
1) Endoscopy with biopsy and negative stool culture is diagnostic.
- Shallow ulceration
- No inflammation beyond submucosa
- Crypt abcesses and goblet cell depletion
2) Stool studies for infective pathogens - to rule out C.difficile
3) Faecal calprotectin - elevated (detects IBD but cannot differentiate between UC or CD)
4) FBC to check for anaemia, infection, thyroid, kidney and liver function
What is the treatment/management for a patient with first presentation or flare of mild to moderate UC?
To induce remission:
First line: oral or rectal aminosalicylate (e.g. sulfasalazine or mesalazine)
Second line: corticosteroids (e.g. prednisolone)
What is the treatment/management for a patient with first presentation or flare of sereve UC?
To induce remission:
Hospitalisation
First line: IV corticosteroids (e.g. hydrocortisone)
Second line: IV ciclosporin
What is the treatment/management for UC in order to maintain remission?
- Oral or rectal aminosalicylate e.g. mesalazine
- Immunosuppressants such as azathioprine or mercaptopurine
Ulcerative colitis: if conventional therapy fails, what treatment can we try?
Third-line treatment: biologics (TNF-alpha inhibitor e.g. infliximab) and Janus kinase inhibitors
Can surgery be considered for patients with UC?
Yes, as UC only affects the rectum and colon, removing them (panproctocolectomy) is curative. However, be aware of post-op complications
Name one complication of UC
Biliary tract carcinoma
Define irritable bowel syndrome (IBS)
Known as a functional bowel disease - no identifiable organic disease underlying the symptoms.
The symptoms result from the abnormal functioning of an otherwise normal bowel.
What are the risk factors for IBS?
- Physical and sexual abuse
- PTSD
- Age <50 years
- Female sex
- GI infections
What are the 3 types of IBS?
IBS-C – with constipation
IBS-D – with diarrhoea
IBS-M – mixed, with alternating constipation & diarrhoea
What symptoms might a patient with IBS experience?
- Diarrhoea
- Constipation
- Fluctuating bowel habit
- Abdominal pain
- Bloating
- Pain worse after eating
- Pain improved by opening bowels
What investigations/tests are used to diagnose IBS?
IBS is considered once other pathologies are ruled out:
- Normal FBC, ESR (erythrocyte sedimentation rate - shows inflammation) and CRP blood tests
- Faecal calprotectin negative to exclude inflammatory bowel disease
- Negative coeliac disease serology (anti-TTG antibodies)
- Cancer is not suspected or excluded if suspected
If the investigations/tests rule out other pathologies, what are the NICE criteria for a diagnosis of IBS?
Symptoms should suggest IBS:
- Abdominal pain/discomfort:
- Relieved on opening bowels, or
Associated with a change in bowel habit
AND 2 of:
- Abnormal stool passage
- Bloating
- Worse symptoms after eating
- PR mucus (rectal discharge)
What is the conservative (non-medical) management plan for IBS?
Reassure patient that no serious pathology is present - important!
Lifestyle management:
- adequate fluid intake
- regular small meals
- reduce processed foods
- limit alcohol and caffeine
- low “FODMAP” diet (ideally with dietitian guidance)
What are the medical management options for IBS?
First-line
- IBS-D - loperamide for diarrhoea
- IBS-C - laxatives for constipation. Not lactulose as it can cause bloating.
- Antispasmodics for cramps e.g. hyoscine butylbromide (Buscopan)
Cognitive Behavioural Therapy (CBT) can help patients manage their IBS
Define coeliac disease
An autoimmune condition where exposure to gluten causes an autoimmune response that results in inflammation of the small bowel.
What is the pathophysiology of coeliac disease?
- Autoantibodies are produced in response to dietary gluten peptides
- Main two autoantibodies are anti-tissue transglutaminase (anti-TTG) and anti-endomysial (anti-EMA)
- They attack the epithelial cells lining the small intestine - causing inflammation, particularly in the jejunum
- Villous atrophy and hyperplasia of the intestinal crypts
What is the aetiology of coeliac disease?
Almost all people with coeliac disease carry one of two major histocompatibility complex class-II molecules (human leukocyte antigen):
- HLA-DQ2 gene (90%)
- HLA-DQ8 gene
What signs and symptoms might a patient with coeliac disease present with?
Often asymptomatic - low threshold for diagnosis
- Failure to thrive in young children
- Diarrhoea
- Fatigue
- Weight loss
- Mouth ulcers
- Anaemia secondary to iron, B12 or folate deficiency
- Dermatitis herpetiformis (an itchy blistering skin rash typically on the abdomen)
Why do we test patients newly diagnosed with T1DM for coeliac disease?
Coeliac disease and T1DM are closely associated and often occur together
What other conditions is coeliac disease associated with?
Several other autoimmune diseases:
- Type 1 Diabetes
- Autoimmune thyroid disease (e.g. Grave’s)
- Autoimmune hepatitis
What investigations/tests are used to diagnose coeliac disease?
Anti-TTG ( tissue-transglutaminase) and anti-EMA are IgA antibodies.
- Total IgA to exclude IgA deficiency before checking for coeliac disease-specific antibodies:
- Raised anti-TTG antibodies (first choice)
- Raised anti-endomysial antibodies
Endoscopy and intestinal biopsy show:
- Crypt hypertrophy
- Villous atrophy
What is the treatment/management for coeliac diease?
- Lifelong gluten-free diet is curative
- However relapse will occur if patient introduces gluten into their diet again
Define gastroenteritis
Acute gastritis is inflammation of the stomach.
Px = nausea and vomiting.
Enteritis is inflammation of the intestines
Px = diarrhoea
Gastroenteritis is inflammation of the stomach to the intestines
Px = nausea, vomiting and diarrhoea.
Define gastritis
The histological presence of gastric mucosal inflammation.
What are the most common causes of gastritis?
- Helicobacter pylori infection
- Non-steroidal anti-inflammatory drugs (NSAIDs)
- Alcohol
What is the pathophysiology of gastritis caused by H.pylori infections?
Gastritis is characterised by acute and chronic inflammation and gastric mucosal protective layer disruption.
H. pylori infection induces a severe inflammatory response with degradation of the protective gastric mucosa layer, increased mucosal permeability, followed by gastric epithelial cell death
What is the pathophysiology of gastritis caused by NSAIDs?
- NSAIDs inhibit COX-1 (cyclo-oxygenase-1)
- COX-1 needed for prostaglandin production
- Prostaglandins stimulate gastric mucus production
- Reduced mucosal defence
What signs and symptoms might a patient with gastritis present with?
- Dyspepsia/epigastric discomfort (non-specific gastritis)
- Nausea
- Vomiting
- Loss of appetite
Make sure there are no red flag symptoms indicating malignancy
- GI bleeding, anaemia, early satiety, unexplained weight loss (>10% body weight), progressive dysphagia, or persistent vomiting
How is gastritis diagnosed?
- Check for presence of risk factors (H.pylori infection, NSAID use, alcohol use)
- H. pylori urea breath test
- H. pylori faecal antigen test
- FBC
How is gastritis caused by H.pylori treated?
H.pylori eradication therapy
Triple therapy with
- PPI (e.g. omeprazole)
- Two antibiotics (amoxicillin/metronidazole & clarithromycin)
7 day course
Stop NSAIDs if patient are using them
Define peptic ulcer disease (PUD)
Peptic ulcer disease involve ulceration of the mucosa of the stomach (gastric ulcer) or the duodenum (duodenal ulcer).
Duodenal ulcers are more common
What is the aetiology of peptide ulcer disease?
Two main causes:
- Gram-negative H.pylori infection (95% duodenal and 75% gastric ulcers)
- Aspirin and NSAID use
There are suggestions that the two causes are associated with each other
What is the pathophysiology of peptic ulcer disease?
The stomach and duodenum has a protective layer comprised of mucus and bicarbonate - secreted by the stomach mucosa.
The stomach and duodenal mucosa is prone to ulceration from:
- Breakdown of the protective layer of the stomach and duodenum by H. pylori, NSAIDs or steroids
- Increase in stomach acid (stress, smoking, alcohol, caffeine, spicy food)
What signs and symptoms might a patient with peptic ulcer disease present with?
- Epigastric discomfort or pain
- Nausea and vomiting
- Dyspepsia (ingestion without cause)
- Bleeding causing haematemesis, “coffee ground” vomiting and melaena
- Iron deficiency anaemia (due to constant bleeding)
What symptom experienced by the patient can help differentiate between a possible gastric or duodenal ulcer?
Eating - worsens pain caused by a gastric ulcer, and improves pain caused by a duodenal ulcer.
Common SBA question
What investigations/tests would you carry out for a patient with suspected peptic ulcer disease?
- Upper gastrointestinal endoscopy - diagnostic for peptic ulcer
- Helicobacter pylori breath test (patient must be free from PPI 2 weeks and Abx 4 weeks)
- Helicobacter pylori stool antigen test (patient must be free from PPI 2 weeks and Abx 4 weeks)
- FBC- microcytic anaemia or high platelet count
What are some differential diagnoses for peptic ulcer disease?
- Oesophageal cancer
- Stomach cancer
- Gastro-oesophageal reflux disease
What is the management for H.pylori negative peptic ulcer disease?
If no active bleeding ulcers:
Proton pump inhibitors (reduce acid secretion in the stomach + allows ulcers to heal)
- Omeprazole
- Lansoprazole
What is the treatment/management for peptic ulcer disease caused by H.pylori infection?
H.pylori eradication therapy + PPI or H2 receptor antagonist for ulcer healing
Triple therapy with
- PPI (e.g. omeprazole)
- Two antibiotics (amoxicillin/metronidazole & clarithromycin)
7-day course
What treatment would you prescribe for a patient with peptic ulcer disease caused by NSAID or aspirin use?
- Consider stopping causative medication use, discuss with specialist as aspirin as secondary prevention for CVD might need to continue
- PPI or H2 receptor antagonist
- Follwoed by H.pylori eradication therapy
What treatment would you prescribe for a patient with peptic ulcer disease caused by NSAID or aspirin use?
- Consider stopping causative medication use, discuss with specialist as aspirin as secondary prevention for CVD might need to continue
- Proton pump inhibitor
- Followed by H.pylori eradication therapy
What monitoring is carried out for patients with peptic ulcer disease?
Endoscopy - ensure ulcer healing and to detect further ulcer development
What are possible complications that can arise from a gastric ulcer?
Upper GI bleeds - low level > chronic anaemia.
Large haemorrhage > life threatening!
Perforation - ulcer creates a hole in the stomach > “acute abdomen” and peritonitis > urgent surgical repair
Scarring and strictures of the muscle and mucosa > narrowing of the pylorus > difficulty with gastric emptying, known as pyloric stenosis.
What are possible complications that can arise from a duodenal ulcer?
- Upper GI bleeds - low level > chronic anaemia.
- Gastroduodenal artery erosion and rupture if ulcer is deeply penerating - DANGER!
Define gastro-oesophageal reflux disease (GORD)
GORD is defined as ‘the condition in which the reflux of gastric contents into the oesophagus results in symptoms and/or complications
What is the aetiology of GORD?
Causes include:
- Increased intraabdominal pressure - e.g. obesity, pregnancy
- Smoking
- Alcohol use
- Hiatus hernia (part of the stomach pushes through the diaphragm)
What is the pathophysiology of GORD?
GORD is a condition where there is reflux of gastric contents back into the oesophagus.
Normally, two mechanisms prevent reflux at gastro-oesophageal junction (GOJ):
- Lower oesophageal sphincter
- Diaphragmatic sphincter
GORD occurs when there is:
- Increased sphincter relaxation
- Rasied intragastic pressure (beyond what the sphincter can cope with) - e.g. Obesity
- Reduced sphincter tone e.g. CCB
- Anatomical abnormalities of GOJ e.g. hiatus hernia
What signs and symptoms might a patient with GORD present with?
Dyspepsia is a non-specific term used to describe indigestion. It covers the symptoms of GORD:
- Heartburn - retrosternal burning chest pain
- Acid regurgitation
- Retrosternal or epigastric pain
- Bloating
- Nocturnal cough
- Hoarse voice
What investigations/tests are used to diagnose GORD?
Endoscopy - assess for peptic ulcers, oesophageal or gastric malignancy.
Patients with evidence of a GI bleed (i.e. melaena or coffee ground vomiting) need admission and urgent endoscopy.
GORD: What red flag symptoms indicate cancer (urgent referral needed - 2-week wait)?
- Dysphagia (difficulty swallowing) at any age
- Aged over 55
- Weight loss
- Upper abdominal pain/reflux
- Treatment resistant dyspepsia
- Nausea and vomiting
- Low haemoglobin
- Raised platelet count
What is the treatment/medical management for GORD?
Acid-neutralising medication when required:
- Gaviscon
- Rennie
PPI
- Omeprazole
- Lansoprazole
Surgery - laparoscopic (Nissen’s) fundoplication.
This involves tying the fundus of the stomach around the lower oesophagus to narrow the lower oesophageal sphincter.
What lifestyle advice is provided for patients with GORD?
Lifestyle advice
- Reduce tea, coffee and alcohol
- Weight loss
- Avoid smoking
- Smaller, lighter meals
- Avoid heavy meals before bed time
- Stay upright after meals rather than lying flat
- Also provided to patients with Barrett’s oesophagus
What are some possible complications that can arise from GORD?
Barrett’s oesophagus - metaplasia of oesophageal epithelium from stratified squamous to columnar epithelium like in the stomach
- Premalignant condition as it is a risk factor for developing adenocarcinoma of the oesophagus (3 - 5% lifetime risk)
What are the risk factors for developing Barrett’s oesophagus?
- GORD
- Male (7:1)
- Caucasian
- FHx
- Hiatus hernia
- Obesity
- Smoking
- Alcohol
A 45-year-old male with a history of GORD and non-compliance with his PPIs presents with severe dysphagia.
What is the most likely diagnosis?
How would you investigate this?
Ix = upper GI endoscopy with biopsy (diagnostic - abnormal epithelium characteristic of Barrett’s oesophagus)
Dx = Barrett’s oesophagus
What is the treatment for Barrett’s oesophagus?
Treatment of underlying reflux:
- PPIs (e.g. omeprazole)
- Lifestyle changes: weight loss, smoking cessation, alcohol abstinence
Low grade dysplasia:
- Repeat surveillance endoscopy every 5 years
High-grade dysplasia
- Ablation treatment during endoscopy using photodynamic therapy
Ablation treatment destroys epithelium so that it is replaced with normal cells
How are patients with Barrett’s oesophagus monitored?
Patients are monitored for adenocarcinoma by regular endoscopy.
Define Mallory Weiss tear
Tear in the oesophageal mucosa resulting in haematemesis (vomiting blood)
What are the aetiology/risk factors of Mallory Weiss tear?
- Recurrent forceful episodes of coughing or vomiting
- Bulimia
- Alcohol
- Acute abdominal blunt trauma
- Hyperemesis gravidarum (severe N+V in pregnancy)
What is the pathophysiology of Mallory Weiss tear?
Pathophysiology not fully understood
Most cases seem to occur due to a sudden rise in abdominal pressure or pressure gradient across the gastro-oesophageal junction with a corresponding low intrathoracic pressure. When these forces are high enough to cause distention in this area, an oesophageal tear may occur
What signs and symptoms might a patient with Mallory Weiss tear present with?
Haematemesis, melaena, symptoms of hypovolemic shock
What investigations/tests would you carry out to diagnose Mallory Weiss tear?
- Upper GI endoscopy: gold standard to assess for tear appearing as red longitudinal defect
- FBC - assess for anaemia secondary to bleeding; usually normal
- U&Es: urea is raised in an upper GI bleed (protein in RBCs is digested into urea in the GI tract)
- LFTs: typically normal but if deranged may raise the possibility of a variceal bleed
- Erect CXR: performed to rule out oesophageal perforation or perforated peptic ulcer
After endoscopy: Rockall score - assess the severity of upper GI bleed pre- and post-endoscopy: <3 = low risk)
What is the treatment/management for Mallory Weiss tear?
- Resuscitation with ABCDE + adrenaline
- Acute treatment: Terlipressin (vasopressin analogue for hypotension) + Urgent Endoscopy
- Rockall Score + Inpatient Observation
- Clip insertion/band ligation to stop bleeding
- Thermocoagulation - using heat to destroy bleeding tissue
Most MWTs resolve spontaneously after 24 hours!