GI/ LIVER Flashcards
What is GORD?
Gastro-oesophageal reflux disease–> Where acid from the stomach refluxes through the lower oesophageal sphincter, irritating the lining of the oesophagus.
What epithelium lines the oesophagus?
Squamous epithelium, making it more sensitive to the effects of stomach acid.
What epithelium does the stomach have?
Columnar epithelium, protecting it against stomach acid.
What is dyspepsia?
Indigestion–> Feeling of burning, pain or discomfort in the digestive tract
What are the symptoms of GORD?
Dyspepsia: Heart burn Acid regurgitation Retrosternal/ epigastric pain Bloating Nocturnal cough Hoarse voice
What is endoscopy used for and when might it be used in GORD?
Patients with evidence of GI bleed or other concerning features would be reffered.
Assesses for peptic ulcers and oesophageal or gastric malignancies.
What are the key red flags that would make you suspicious of cancer and therefore need a 2 week endoscopy referral?
Dysphagia Over 55 Weight loss Upper abdominal pain/ reflux Treatment resistant dyspepsia Nausea/ vomiting Low haemoglobin/ raised platelets
What lifestyle advice would be given to patients with GORD?
Reduce tea, coffee and alcohol Weight loss Avoid smoking Smaller, lighter meals Avoid heavy meals before bed Stay upright after meals
What medication can be given to manage GORD?
Acid neutralising medicine-> Gaviscon/ Rennie
Proton pump inhibitors (reduce acid secretion)–> Omeprazole/ Lansoprazole
Ranitidine
What is Ranitidine and its action?
Medicine used as an alternative to PPIs to treat GORD. H2 receptor antagonist which reduces stomach acid.
What is the surgery that can be used to treat GORD called?
Laparoscopic fundoplication–> Ties the fundus of the stomach around the lower oesophagus to lower the sphincter.
What stomach bacteria test is offered to anyone with dyspepsia and what kind of bacteria is it?
Helicobacter pylori
Gram negative aerobic bacteria
How does H. pylori avoid the acidic environment in the stomach?
Forces its way into the gastric mucosa
How does H. pylori cause damage?
Causes breaks in the mucosa, exposing the epithelial cells underneath to acid and causing gastritis, ulcers and increased risk of stomach cancer.
What does H. pylori produce to neutralise stomach acid and how does this cause damage?
Ammonia which directly damages epithelial cells.
What tests can be used to look for H. pylori?
Urea breath test
Stool antigen test
Rapid urease test
What is a rapid urease test?
Small biopsy taken of the stomach mucosa during endoscopy. Urea is added to the sample and if H. pylori is present, they produce enzymes that convert the urea to ammonia.
How is H. pylori eradicated?
Triple therapy: Proton pump inhibitor + 2 antibiotics for 7 days
What is Barretts oesophagus?
When the oesophagus epithelium changes from squamous to columnar due to constant acid reflux. (metaplasia).
Why do patients with Barrets oesophagus have to be monitored with regular endoscopy?
It is premalignant and increases the risk of adenocarcinoma development.
How can Barretts oesophagus be treated?
Proton pump inhibitors, ablation treatment during endoscopy.
Where do peptic ulcers most commonly form?
Duodenum (and stomach)
Why do ulcers form?
When there is a breakdown in the protective layer of the stomach or duodenum and an increase in stomach acid.
What makes up the protective layer of the stomach and how can it be broken down?
Mucus and bicarbonate
Can be broken down by medications (Steroids or NSAIDs) or H. Pylori
What can cause an increase in stomach acid?
Stress Alcohol Caffeine Smoking Spicy foods
What are the key presentations of a peptic ulcer?
Epigastric discomfort or pain Nausea and vomiting Dyspepsia Bleeding--> causes haematemesis, 'coffee gound' vomiting and melaena Iron deficiency anaemia
How might you tell the difference between a gastric and duodenal ulcer in terms of their presentation?
Eating worsens pain of gastric ulcers and improves pain of duodenal ulcers.
What is haematemesis?
Vomiting blood
How are peptic ulcers diagnosed?
Endoscopy
(Rapid urease/ CLO test can be performed to check for H. Pylori)
*Biopsy should be considered to exclude malignancy.
How are peptic ulcers treated?
Same as GORD–> usually with high dose proton pump inhibitors.
What complications can peptic ulcers cause?
- Bleeding from ulcer (common and potentially life threatening)
- Perforation resulting in acute abdomen and peritonitis.
- Scarring and strictures of the muscle and mucosa, leading to pyloric stenosis.
What is pyloric stenosis and how does it present?
Narrowing of the pylorus (stomach exit), leading to difficulty in emptying stomach contents. Presents with upper abdominal pain, distention, nausea and vomiting.
What are the causes of an upper GI bleed?
- Oesophageal varices (enlarged veins)
- Mallory-Weiss tear (tear of mucous membrane)
- Peptic ulcers
- Stomach/ duodenal cancers
How do upper GI bleeds present?
- Haematemesis
- ‘Coffee ground’ vomit
- Melaena
- Haemodynamic instability causes large blood loss, causing low blood pressure, tachycardia and other signs of shock
- Symptoms of underlying pathology–> e.g. epigastric pain/ dyspepsia in peptic uclers
What causes ‘coffee ground’ vomit?
Vomiting digested blood that looks like coffee grounds
What is melaena?
Tar like, black greasy stool caused by digested blood.
What is the Glasgow-Blatchford score?
Scoring system in suspected upper GI bleed that scores patients based on their clinical presentation. >0 indicates high risk for upper GI bleed
What features are taken into account in the Glasgow-Blatchford score that indicate an upper GI bleed?
- Drop in Hb
- Rise in urea
- Blood pressure
- Heart rate
- Melaena
- Syncopy
Why do urea levels rise in upper GI bleeds?
Blood in the GI tract gets broken down by the acid and digestive enzymes, releasing urea which is then absorbed in the intestines.
What is the Rockall score?
Used for patients that have had an endoscopy to calculate their risk of rebleeding and overall mortality.
How is an upper GI bleed managed?
ABATED: ABCDE approach to immediate resuscitation Bloods Access (cannula) Transfuse Endoscopy Drugs (stop anticoagulants and NSAIDs)
What is looked for in the bloods taken for a suspected GI bleed?
Haemoglobin (FBC) Urea (U&E's) Coagulation (INR. FBC for platelets) Liver diease (LFTs) Crossmatch
What are the two main types of inflammatory bowel disease?
Ulcerative colitis and Crohn’s disease
What are common of both crohn’s and ulcerative colitis?
Both involve inflammation of the walls of the GI tract and have periods of remission and exacerbation
What makes Crohn’s different to Ulcerative colitis? (NESTS)
No blood or mucus
Entire GI tract
Skip lesions (patchy inflammation)
Terminal ileum most affected and Transmural (full thickness) inflammation
Smoking is a risk factor
Also associated with weight loss, strictures and fistulas
What makes Ulcerative Colitis different to Crohn’s?
Continuous inflammation Limited to colon and rectum Only superficial mucosa affected Smoking is protective Excrete blood and mucus Use aminosalicylates to treat Primary sclerosing cholangitis
What are the main presentations of inflammatory bowel disease?
Diarrhoea
Abdominal pain
Passing blood
Weight loss
How is inflammatory bowel disease tested for?
- Endsocopy with biopsy–> Diagnostic.
- Routine bloods for anaemia, infection, thryoid, kidney and liver function
- CRP indicates inflammation and active disease
- Faecal calprotectin
- Imaging to look to complications
What is Faecal calprotectin ?
Useful screening test for IBD—> Protein released by intestines when they are inflamed
What is the first line treatment for inducing remission in Crohn’s? What can be added if these don’t work alone
Steroids (e.g. oral prednisolone or IV hydrocortisone)
Can add immunosuppressant
What are the first line medications offered to Crohn’s patients to maintain remission?
Azathioprine
Mercaptopurine
When can surgery be offered to those with Crohn’s?
When the disease only affects the distal ileum, it is possible to surgically resect it and prevent further flares.
Can be used to treat secondary strictures and fistulas.
How is mild-moderate Ulcerative colitis treated to induce remission?
First line: Aminosalicylate
Second line: Corticosteroids
How is severe ulcerative colitis treated to induce remission?
First line: IV corticosteroids
Second line: IV ciclosporin
How can the disease be removed in ulcerative colitis?
Panproctocolectomy–> Removing colon and rectum will remove the disease.
What are the two outcomes of surgery used to treat ulcerative colitis?
Permanent ileostomy or ileo-anal anastomosis (J-pouch)
What is a J-pouch?
When the colon and rectum are removed and the ileum is folded back in itself and fashioned into a larger pouch that functions like a rectum. It is attached to the anus and collects stools.
What is Colostomy Surgery?
Part of the colon is removed, and a stoma is created- stoma is when part of the intestine is pulled through the abdominal wall to create an opening through which stool leaves the body.
What is IBS?
Functional bowel disorder- no identifiable organic disease underlying the gut symptoms.
How much of the population has IBS and who are more affectesd?
Up to 20% of population.
More common in women and young people.
What are the main symptoms of IBS?
Diarrhoea Constipation Fluctuating bowel habits Abdominal pain Bloating (Worse after eating, improved by opening bowels)
What is the criteria for diagnosis of IBS?
Diagnosis of exclusion:
- Normal FBC, EST, CRP blood tests
- Negative faecal calprotectin
- Negative coeliac disease serology
- Cancer excluded/ not suspected
- Symptoms that suggest IBS
What is the firstline management of IBS?
Lifestyle advice:
- Adequate fluid intake
- Regular small meals
- Limit processed foods, caffeine and alcohol
- Low FODMAP diet
- Trial of probiotic
- CBT
What is are the medication treatment options for IBS?
First line: -Loperamide for diarrheoa -Laxatives for constipation -Antispasmodics for cramps Second line: - Tricyclic antidepressants Third line: -SSRIs antidepressants
What is coeliac disease?
Autoimmune condition where exposure to gluten causes an autoimmune reaction that causes inflammation in the small bowel.
When does coeliac disease usually develop?
In early childhood (but can at any age)
What are the two auto-antibodies involved in coeliac disease?
- Anti-tissue transglutaminase (anti-TTG)
- Anti-endomysial (anti-EMA)
What happens on exposure to gluten in coeliac disease?
Auto-antibodies are created that target the epithelial cells of the intestine and lead to inflammation.
Where does inflammation caused by coeliac disease particularly affect and what does it cause?
Affects small bowel- especially jejunum
Causes atrophy of intestinal villi which causes malabsorption of nutrients and the symptoms of disease
How does coeliac disease present?
Often asymptomatic
- Failure to thrive in children
- Diarrhoea
- Fatigue
- Weight loss
- Mouth ulcers
- Anaemia (secondary to iron, B12 or folate deficiency)
- Dermatitis herpetiformis (Skin rash)
- Occasional neurological symptoms
What are the genetic associations with coeliac disease?
HLA-DQ2 (90%)
HLA-DQ8 gene
How is coeliac disease tested?
- Investigations must be carried out whilst the patient is on a diet the contains gluten.
- Check IgA levels to exclude IgA deficiency.
- Antibody tests: Raised anti-TGG and anti endomysial antibodies
- Endoscopy and intestinal biopsy–> Show crypt hypertrophy and villous atrophy.
What other conditions is coeliac disease associated with?
Type 1 diabetes Thyroid disease Autoimmune hepatitis Primary biliary cirrhosis Primary sclerosing cholangitis
What are the complications of untreated coeliac disease?
Vitamin deficiency Anaemia Osteoporosis Ulcerative jejunitis Enteropathy-associated T-cell lymphoma of intestine Non-Hodgkin lymphoma Small bowel adenocarcinoma
What is the treatment of coeliac disease?
Lifelong gluten-free diet
What is a Mallory-Weiss tear and what usually causes it?
Linear mucosal tear at the oesophagastric junction that causes an upper GI bleed. Caused by a sudden increase in intra-abdominal pressure (e.g. coughing, retching, dry-heaves)
What cells does the mucose of the upper two thirds of the stomach contain?
Parietal cells
Chief cells
Enterochromaffin-like cells (ECL)
What do parietal cells secrete?
HCl
What do Chief cells secrete and what does this initiate?
Pepsinogen which initiates proteolysis
What do ECL cells release and what does this stimulate?
Histamine- stimulates acid release
What cells does the antral contain and what do they secrete?
Mucus secreting cells–> Release mucin and bicarbonate
G cells–> Secrete gastrin (stimulate acid release)
D cells–> Secrete somatostatin (suppresses acid secretion)
What is achalasia?
Failure of the LES to relax/ open during swallowing.
How does achalasia present?
Intermittent dysphagia (of both solids and liquids)
Regurgitation of food
Substernal cramps
What is scleroderma?
Systemic sclerosis–> a chronic autoimmune disease that causes hardening of connective tissue.
How does scleroderma affect the GI tract?
Diminished peristalsis and oesophageal clearance due to replacement of smooth muscle by fibrous tissue.
Causes GORD.
What is the definition of diarrhoea?
Loose/ liquid stools more than 3 times daily
What is acute diarrhoea?
Diarrhoea lasting < 14 days
What is persistent diarrhoea?
Diarrhoea lasting 14-30 days
What is chronic diarrhoea?
Diarrhoea lasting >14 days
What are the main non-infective causes of diarrhoea?
Cancer IBD IBS Hormonal Radiation Chemical (antibiotics) Anatomical
What are the main infective causes of diarrhoea?
Viral
Bacteria
Parasites
What antibiotics can give rise to diarrhoea?
Climpamycin, Ciprofloxacin, Co-amoxiclav, Cephalosporins can all give rise to C.Diff
What are the main viral causes of diarrhoea?
Rotavirus, Norovirus
What are the main bacterial causes of diarrhoea?
Campylobacter, Shigellla, Salmonella, S.aureus, B.cereus, E.coli, C.Diff, Cholera
What are the main parasitic causes of diarrhoea?
Giardia, crypto.
What causes watery diarrhoea?
Non-inflammatory causes (enterotoxins or superficial adherence/ invasion)
What causes bloody/ mucoid diarrhoea?
Inflammatory causes (invasion/ cytotoxins)
What is gastroenteritis?
Inflammation all the way from the stomach to the intestines that presents with nausea, vomiting and diarrhoea
What is dysentery?
Infectious gastroenteritis with bloody diarrhoea
What is norovirus and how long does it last?
Single-stranded RNA virus. Lasts 24-72 hours.
What is rotavirus and how long does it last?
Double stranded RNA virus. Lasts 3-8 days.
What is E.coli and what does it produce that causes diarrhoea?
Gram -ve bacteria that produces Shiga toxin.
What does Shiga toxin do?
Causes abdominal cramps, bloody diarrhoea and vomiting. Also destroys blood cells which leads to haemolytic uraemic syndrome.
What is campylobacter and what causes it?
Gram negative bacteria- main cause of travellers diarrhoea. Caused by raw/ improperly cooked poultry, untreated water and unpasteurised milk.
What is shigella and how is it spread?
Bacteria spread by faeces contaminated water, pools and food.
What is salmonella and how is it spread?
Bacteria spread by raw eggs, poultry or food contaminated with infected faeces of small animals.
What is Bacillus Cereus and how is it spread?
Gram positive bacteria spread through inappropriately cooked foods. Common on food not refrigerated immediately (e.g. rice)
After how long does Bacillus Cereus cause symptoms and how long does it last?
Cramping and vomiting within 5 hours of ingestion.
Watery diarrhoea after 8 hours when it reaches the intestines.
Resolves within 24 hours.
What is Yersinia Enterocolitica and how is it spread?
Gram -ve bacillus spread by raw/ undercooked pork, and contamintation with the urine/ faeces of other mammals/
How long is Yersinia Enterocolitica incubation and how long does it last?
incubation is 4-7 days.
Can last 3 weeks or more.
How does Staph. Aureus cause infection?
Produces enterotoxins when growing on food. that cause enteritis.
What is giardia lamblia and how does it spread?
Microscopic parasite that lives in intestines of mammales and releases cysts in their stools. These can then contaminate food or water.
What does the pancreas consist of?
Exocrine (98%) and Endocrine cells
What is the function of the exocrine pancreas?
Secretion of digestive enzymes, ions and water into the duodenum.
What is the functional unit of the exocrine pancreas?
Acinus and its draining ductule
Where does the pancreatic duct enter the duodenum?
Joins to the common bile duct to enter at the ampulla of Vater.
What digestive enzymes do acinar cells produce?
Amylase, lipase, colipase, phospholipase, proteases
What is the action of the endocrine pancreas?
Release hormones into blood to control blood glucose levels
What cells does the endocrine pancreas contain and what do they secrete?
Alpha cells- glucagon Beta cells - insulin Delta cells- somatostatin Pancreatic polypeptide cells Enterochrommaffin cells - serotonin.
What is acute pancreatitis?
Rapid onset of pancreatic inflammation and symptoms
What is chronic pancreatitis?
Longer-term inflammation and symptoms with progressive and permanent deterioration in pancreatic function.
What are the three main causes of pancreatitis?
Gallstones
Alcohol
Post-ERCP
What is ERCP?
Procedure that uses an endoscope and X-rays to look at your bile duct and your pancreatic duct.
What is gallstone pancreatitis?
When gallstones get trapped at the ampulla of Vater, blocking the flow of bile and pancreatic juice into the duodenum and resulting in inflammation of the pancreas.
Why does alcohol cause pancreatitis?
Alcohol is directly toxic to pancreatic cells, resulting in inflammation.
What are the causes of pancreatitis?
I GET SMASHED: Idiopathic Gallstones Ethanol (alcohol) Trauma Steroids Mumps Autoimmune Scorpion sting Hyperlipidaemia ERCP Drugs
What are the main presentations of acute pancreatitis?
Severe epigastric pain Pain that radiates to the back Vomiting Abdominal tenderness Systemically unwell (fever, tachycardia)
What are the initial investigations of pancreatitis?
Glasgow score Amylase--> Raised to >3X normal C-reactive protein- monitors inflammation Ultrasound (assesses for gallstones) CT abdomen (assesses for complications)
What is the Glasgow score and what is the criteria needed to work it out?
Used to assess severity of pancreatitis. (0-1= mild 2= moderate 3 or more= severe) PANCREAS pneumonicL Pa02<60 Age >55 Neutrophils (WBC>15) Calcium <2 uRea >16 Enzymes Albumin Sugar (glucose>10)
How is acute pancreatitis managed?
Resuscitation (ABCDE) IV fluids Nil by mouth Analgesia Careful monitoring Treatment of gallstones if needed Antibiotics if needed Treatment of complications
What are the main complications of acute pancreatitis?
Necrosis Infection Abscess formation Acute peripancreatic fluid collections Pseudocysts Chronic pancreatitis
What does chronic pancreatitis cause?
Fibrosis and reduced pancreatic function
What is the most common cause of chronic pancreatitis?
Alcohol
What are the key complications of chronic pancreatitis?
Chronic epigastric pain
Exocrine function loss causing lack of pancreatic enzymes
Endocrine function loss leading to diabetes
Damafe and strictures to duct system causing obstruction in excretion of pancreatic juice and bie
Formation of pseudocysts and abscesses
How is chronic pancreatitis managed?
Abstain form alcohol/ smoking
Analgesia
Replacement of pancreatic enzymes
Subcutaneous insulin regimes if diabetes develops
ERCP with stenting to treat strictures and obstruction.
Surgery may be required.
What are the main functions of the liver?
- Glucose and fat metabolism
- Detoxification and excretion–> Bilirubin, ammonia, drugs, hormones
- Protein synthesis–> Albumin, clotting factors
- Defence against infection
What are the main causes of acute liver injury?
Viral (A,B,EBV) Drugs Alcohol Vascular Obstruction Congestion
What are the main causes of chronic liver injury?
Alcohol
Viral (B,C)
Autoimmune
Metabolic (iron, copper)