Gastroenterology Flashcards
What is gastro-oesophageal reflux disease (GORD)?
Retrograde flow of gastric contents into oesophagus. Rarely life threatening but frequently chronic and affects QOL, heart pain and can induce premalignant change in esophagus.
What is the anti-reflux barrier?
Lower oesophageal sphincter (LOS) has transient changes in pressure - GORD have lower LOS pressures on average
Diaphragm acts as external sphincter
What is in the refluxed material?
Acid and pepsin
What are the oesophageal defence mechanisms?
- Oesophageal clearance = gravity and peristalsis (?peristaltic dysfunction or hiatus hernia if oesophageal clearance impaired)
- Saliva contains bicarbonate to neutralise acid
- Oesophageal mucosa = mucous, bicarbonate and prostaglandins are protective
What are the risk factors for GORD?
- Pregnancy (pressure against diaphragm)
- Hiatus hernia
- Genetic
- Smokers
- Obesity
- Large meals late at night
- High fat content
- Excess alcohol or caffeine
- Drugs e.g. TCAs, anticholinergics, nitrates, Ca blockers
What are the symptoms of GORD?
- Heartburn related to meals, lying down, relieved by antacids
- Retrosternal discomfort
- Acid brash - regurgitation acid or bile
- Water brash - excessive salivation
- Odynophagia - pain on swallowing due to sever oesophagitis or stricture
What are the atypical symptoms of GORD?
Non-cardiac chest pains
Dental erosions
Respiratory symptoms: asthmatic symptoms ie wheeze, laryngitis, chronic cough, chronic hoarseness
Episodic or chronic aspiration can cause pneumonia, lung abscess and interstitial pulmonary fibrosis
In GORD, what symptoms are alarm symptoms and should be referred immediately?
- Acute GI bleed
- Dyspepsia (indigestion) with:
a) chronic GI bleed
b) Progressive unintentional weight loss
c) Progressive difficulty swallowing
d) Persistent vomiting
e) Iron deficiency anaemia
f) Epigastric mass
What is the management of GORD?
- Drug tx with PPI omeprazole
- Lose weight
What are the causes of upper GI bleeding?
- Peptic ulcer disease
- Duodenitis
- Gastritis
- Varix rupture (varicose veins rupture lower oesophagus)
- Oesophagitis
What are the signs and symptoms of upper GI bleeding?
- General abdominal discomfort
- Haematemesis (vomiting of blood)
- Malaena (blood rectally)
- Shock (from loss of blood)
- Changes in orthostatic vital signs
What are the causes of oesphageal varices (where varicose veins at lower end of oesophagus get larger and burst)?
Portal hypertension:
- Chronic alcohol abuse and liver cirrhosis
- Ingestion of caustic substances
What is the pathophysiology of peptic ulcers?
Erosions caused by gastric acid. Defect in the gastric or duodenal wall that extends through the muscularis mucosae into deeper layers of wall (submucosa or muscularis). Can erode through major blood vessels causing haemorrhage
What are the causes of peptic ulcers?
Drugs - NSAIDs, corticosteroid use Alcohol/tobacco use H.pylori Stress Changes in gastric mucin consistency (may be genetically determined
What are the signs and symptoms of peptic ulcers?
Abdominal pain
Haematemesis and melaena if haemorrhagic rupture
What is the treatment of peptic ulcers?
Surgery only if haemorrhage or perforation.
Must reduce acid secretion, neutralise the acid secretion and protect mucosa
Consider histamine blockers (H2 receptor antagonists), prostaglandin analogues, antacids, PPIs, chelates, antibiotics
What are the signs and symptoms of Crohns disease?
Diarrhoea GI bleeding Nausea/vomiting Abdominal pain/cramping - intestinal obstruction and acute inflammation (appendicitis like) Fever Weight loss
What are the oral signs and symptoms of Chrohns disease?
Cobblestone mucosa
Granulomatous lesions (swollen lower lip, angular cheilitis)
Generalised inflammation
Recurrent aphthous stomatitis
Where do apthous ulcers most commonly present?
Inside of lips, cheeks, on tongue, on base of gums
Does ulcerative colitis have any oral manifestations
No - but secondary to iron deficiency anaemia
What conditions can cause apthous-like ulcers?
- Immune system disorders
- Blood diseases e.g. HIV
- Vitamin deficiencies
- Hormonal e.g. menstrual
- Allergies
- Stress
- Trauma
- GIT problems e.g. Crohns, coeliac disease
What is the treatment for oesophageal varices?
Propanalol to lower BP
What diseases make up inflammatory bowel disease?
Ulcerative colitis = muscosal ulceration in colon
Crohns disease = transmural inflammation in anypart of GI tract
Why is IBS different to IBD?
It is a diagnosis of exclusion
What is the age and sex incidence of inflammatory bowel disease?
Tends to affect younger people Familial pattern (10-25% concordance) but genetic and environmental factors still unresolved
What are the drug groups used in inflammatory bowel disease?
- Symptomatic agents e.g. antispasmodics
- 5-ASA compounds (based on aspirin to reduce inflammation) e.g. sulfasalazine
- Corticoids
- Immunosuppressive
- Antibiotics e.g. metronidazole (against anaerobic)
What is a fistula?
Pathological tract between 2 surfaces and lined with epithelium
What does a barium contrast study show?
Obstructions - black areas = strictures which can lead to infarction of the bowel
What can transmural inflammation develop?
Fistulae
What are the types of fistulae that can be present in the GI tract?
- Mesenteric
- Entero-enteric
- Entero-vesical (bowel and bladder)
- Retroperitoneal
- Entero-cutaneous (bowel and skin e.g. through surgical scar or umbilicus)
- Perianal
What are the systemic complications of IBD?
- Aphthous stomatitis
- Episcleritis (red eye) and uveitis (uneven pupil)
- Arthritis - peripheral large joints, monoarticular - central ankylosing spondylitis and sacroiliitis (base of spine)
- Vascular complications
- E.nodosum causing painful skin rash
- P.gangrenosum on outside of ankle
- Gallstones
- Malabsorption
- Renal stones, fistulae, hydronephrosis, amyloidosis (deposits beta pleated sheets)
- Bleeding with bowel movements - can lead to iron deficiency anaemia (hypochromic, microcytic)
- Malignancy ie colorectal cancer in ulcerative colitis
What two diseases is granulomas seen in and is tested with serum angiotensin converting enzyme to differentiate?
Crohns
Sarcoidosis
What is proctocolitis and which patients is it seen in?
Inflammation of the colon
- Ulcerative colitis
- Crohns
- Radiation pts
- Ischaemia
- Infections with C.diff
- From antibiotics
What is a complication of non-universal ulcerative colitis?
Toxic dilatation/megacolon - can perforate leading to air in abdominal cavity, sepsis and multiorgan failure
What are the indications for surgery in non-universal ulcerative colitis?
- Exsanguinating haemorrhage (pt will bleed to death)
- Growth retardation
- Systemic complications
- Toxicity and/or perforation
- Suspected cancer
- Significant dysplasia (pre-cancerous)
- Intractability
What is the management of non-universal ulcerative colitis?
Medical
Colonectomy will cure condition
What are the features of a peptic duodenal ulcer?
- Intermittent epigastric pain usually post-prandial (1-3hrs post food)
- Posterior ulcer may radiate pain to back
- Haemorrhage - more rapid bleeding = melena (blleding rectal), slower = anaemia.
- H.Pylori in 90%
What are the features of benign peptic gastric ulcer?
- Intermittent epigastric pain
- Chronic
- Can perforate
- H.Pylori in 60%
If a benign peptic gastric ulcer has perforated, what is seen on a chest xray?
Gas under right hemidiaphragm - surgical emergency as free gas in abdominal cavity. (left air normal as this is gastric bubble)
What 3 things are ulcer producing?
What 3 things are protective against ulcers?
Gastric acid, pepsin, H.pylori infection
Prostaglandins, mucus, HCO3-
How do H2 receptor antagonists work in the management of peptic ulcers? Give examples of drugs
Block histamine receptors to reduce gastric acid output
Cimetidine (most popular), Famotidine, Nizatidine, Ranitidine (can be used in hospital)
How do prostaglandin analogues work in the management of peptic ulcers? What drug is most used?
Inhibit gastric acid secretion. PGE2 and PGI2 stimulate mucus and bicarbonate
Inhibit adenylcyclase to reduce cAMP production
Misoprostol (PGE2 analogue)
How do proton pump inhibitors (PPIs) work in the management of peptic ulcers? Give examples of drugs EXAM Q!!
Final step in acid production is action of H+/K+ ATPase (proton pump). PPIs act to inhibit this enzyme. THey are pro-drugs and are activated in an acidic environment
Omeprazole Lansoprazole Esomeprazole Pantoprazole Rabeprazole
How do antacids work in the management of peptic ulcers? What drug is most used?
Weak bases that interact with gastric acid to produce salts. Raise the gastric pH which inactivates pepsin. Magnesium hydroxide, aluminium hydroxide
What are the side effects of magnesium salts? Aluminium salts?
Diarrhoea
Constipation
How do chelates and complexes work in the management of peptic ulcers? Give drug examples
Protect the gastric and duodenal mucosa by coating mucosa. Stimulate bicarbonate and mucous secretion. Inhibit action of pepsin.
Bismuth chelate
Sucralfate (aluminium hydroxide and sulphated sucrose)
How is the presence of H.Pylori in peptic ulcers confirmed?
Blood, breath, stool, biopsy
How is H.pylori eliminated in peptic ulcers
Triple therapy for 1 week:
- PPI
- Clarithromycin
- Metronidazole or amoxicillin
What are the drug interactions of sucralfate (chelate)?
Reduces effects of warfarin
Inhibits absorption of teracycline, ketoconazole and amphotericin
What are the drug interactions of antacids?
Reduced absorption of tetracycline
What are the drug interactions of omeprazole (PPI)?
Inhibits metabolism of diazepam
Inhibits absorption of ketoconazole and itraconazole
Increases effects of warfarin
What are the drug interactions of Cimetidine (H2 receptor antagonist)?
Inhibits absorption of ketoconazole and itraconazole
Inhibits metabolism of anticoagulants, erythromycin, carbamazepine, metronidazole, benzodiazepines and bupivacaine
What are the adverse reactions to Ranitidine (H2 receptor antagonist)?
Erythema multiforme and staining of tongue
What are the adverse reactions to Sucralfate (chelate)?
Xerostomia and metallic taste
What are the adverse reactions to H2 receptor antagonists?
Pain and swelling of salivary glands
What is a side effect of omeprazole?
Dry mouth
What peptic ulcer drug leaves a chalky taste in the mouth?
Antacids
What are the systemic causes of dysphagia?
- Myasthenia Gravis
- Psychological
- Muscle weakness
- Multiple sclerosis
- Parkinsons
- Pseudobulbar palsy (upper motor neurone lesion)
What investigations can be carried out for the oesophagus?
- Oesophagoscopy (OGD)
- Barium swallow (show where strictures are, details of motion)
- CT scan (stages of cancer)
- Oesophageal pressure monitoring
- 24hr pH monitoring (reflux)
What other therapeutic options does an OGD offer?
Dilation, stenting, removal of bolus obstruction, sclerotherapy (for GI bleeds)
What investigations can be carried out for the stomach?
- Gastroscopy (direct vision and biopsy)
- CT scan
- Barium meal (used less)
What investigations can be carried out for the duodenum?
- OGD gastro-duodenoscopy
- Limited view of jejunum - jejunal biopsy (coeliac disease)
- CT for adjacent and associated structures
What are symptoms of small bowel disorders?
Pain/colic - comes in waves
Malabsorption - fatigue and systemic illness
Bleeding
Vomiting
What tumour of the small bowel is very rare?
Carcinoid tumour - originates from endocrine cells - flushing oedema and abdominal cramping
The jejunum and ileum are difficult to investigate - what investigations have some value?
- CT scan
- Special isotope scans - labels RVCs so can see bleeding
- Angiography - can be helpful in GI haemorrhage
What is diverticulitis?
Outpouching of large bowel becomes inflamed - associated with lower left quadrant pain
What investigations can be carried out for the large bowel?
Colonoscopy/ flexible sigmoidoscopy - for biospy, polypectomy, stenting, laser treatment
Barium enema
What investigations can be carried out for ano-rectal?
Direct vision Digital examination Proctoscopy/rigid sigmoidoscopy Flexible sigmoidoscopy (for higher up) Examination under anaestethic Complex radiological assessments e.g. pelvic CT or transrectal ultrasound
What is normal bowel habit?
Bowel movement between 3x day and once every 3 days
What medications commonly cause indigestion?
Aspirin
Bisphosphonates
NSAIDs
What are the indications for a colonoscopy?
Change of bowel habit
Bleeding
Surveillance in ulcerative colitis or polyposis
Diagnosis of non cancerous colonic conditions e.g. Crohns
Screening
What conditions can affect the ano-rectal part of GI system?
IBD e.g. ulcerative colitis Carcinoma of rectum Haemorrhoids Fissure Fistula (tract from bowel to skin often in Crohns)
Why is a hiatus hernia important if the patient has an anaesthetic?
Causes acid reflux
Can result in acid ‘spill over’ under GA - risk of aspiration pneumonia
What are the common causes of rectal bleeding?
Haemorrhoids Anal fissure Diverticular disease Cancer Collitis (infective and inflammatory) Vascular malformation
What can a sigmoidoscopy view?
Lower third of colon up through rectum
Where is the gallbladder positioned? What is its role?
At head of pancreas in groove of duodenum then extends across left abdomen where tail sits in spleen behind stomach.
Stores bile in between meals
What are the 3 benign hepatico-pancreatic biliary (HPB) diseases?
Biliary obstruction e.g. stone disease (choledocholithiasis), strictures
Pacreatitis
Gallbladder disease e.g. gallstones
What are the 3 malignant HPB diseases?
Liver tumpurs- hepatocellular carcinoma, intrahepatic cholangiocarcinoma, metastatic disease
Biliary tumours - cholangiocarcinoma
Pancreatic tumours - pancreatic ductal adenocarcinoma, periampullary tumours
How does biliary disease present?
Pain - epigastric or right upper quadrant of abdomen, may radiate into back
Jaundice - yellowing skin/sclera, intractable itch
Nausea/vomiting
Weight loss
Pancreatic exocrine insufficiency - pale greasy stool, excessive flatulence
Poor diabetic control
What are the causes of acute pain and chronic pain in biliary disease?
Acute = gallstones, pancreatitis Chronic = malignancy or chronic pancreatitis
What type of stones are predominant in gallstone disease?
Cholesterol stone (bile saturated with cholesterol) Pigment stones rare in west
What is biliary colic? What is the treatment?
Pain typically after eating and self limiting over 30mins-2hrs
No systemic upset
Tx: cholecystectomy, non emergency, surgery to remove gallbladder
What is acute cholecystitis? What is the treatment?
Pain typically after eating not self limiting
Associated with fever
Stone in neck of gallbladder, distention gallbladder, inflamed and ischaemic
Treatment with antibiotics and emergency cholecystectomy
What is obstructive jaundice?
Painful - typically associated with stones in the bile duct
Painless - biliary strictures or malignancy
How is obstructive jaundice differentiated from non-obstructive jaundice?
- History
- LFTs - increased alkaline phosphatase, gamma GT, increased ALT
- Biliary dilation on imaging by ultrasound
What is ascending cholangitis?
Medical emergency - charcot’s traid of fever pain and jaundice due to infection in obstructed bile duct. Will need urgent biliary decompression, antibiotic therapy and resuscitation
Why do patients with obstructive jaundice have abnormal coagulation?
Bile essential for fat absorption, vit K absorbed with fat - essential for clotting factors. Prolonged prothrombin time
What is endoscopic retrograde cholangio-pancreatography (ERCP)?
What is used for?
What are the risks?
Endoscopic procedure with access to biliary tree via ampulla of vater. (if obstruction below hylem then down oropharynx into stomach)
Uses: clear gallstones, stent strictures
Risks: pancreatitis, bleeding, perforation of duodenum
What is percutaneous transhepatic cholangiography?
What is it useful for?
What are the main risks?
Percutaneous radiological procedure under ultrasound guidance
Uses: for failed ERCP or more proximal biliary obstruction
Risks: Bile leak, bleeding, pancreatitis (rare)
What is required for diagnosis of acute pancreatitis?
1) Hyperamylasaemia - exocrine enzymes of pancreas increased in blood
2) Appropriate symptoms - upper abdo pain into back
3) Appropriate imaging
What is the aetiology of pancreatitis?
Gallstones (50%) Alcohol (25%) Drugs e.g. steroid, methotrexate, azathioprine, sodium valporate Hyperlipidaemia Autoimmune (IgG4) Hypercalcaemia
What is severe acute pancreatitis defined as?
Multiorgan failure persisting more than 48 hours or the development of late complications which may require intervention (>4weeks) e.g. pancreatic necrosis
What is the management of
a) mild acute pancreatitis?
b) severe acute pancreatitis?
a) fluids, pain control, remove cause e.g. gallstones within 2 weeks
b) organ, nutritional support and intensive care. Manage complication and underlying cause
What can be seen on a CT scan in pancreatitis?
Autodigestion and necrosis. Gas and fluid in retroperitoneum
What is chronic pancreatitis?
Chronic inflammatory process characterised by gland fibrosis with loss of parenchymal function and development to strictures within pancreatic duct
What are the clinical features of chronic pancreatitis?
Pain, exocrine insufficiency e.g. pale greasy stool, endocrine insufficiency e.g. diabetes, jaundice
What are the causes of chronic pancreatitis?
- Alcohol
- Recurrent acute inflammation
- Autoimmune
- Tropical (India)
- Genetic e.g. CFTR (cystic fibrosis)
What thing in a patients history may you think indicates cancer and you must signpost for?
- Dysphagia
If a patient is predisposed to gastritis but you need to prescribe an NSAID, what should you prescribe alongside it?
PPI e.g. omeprazole
On examination, if a patient has finger clubbing what GI disorders may be the cause?
GI lymphoma, inflammatory disorder e.g. Crohns
On examination, what are these two signs that are indicative of GI disorders? Ascites and scaphoid abdomen
Ascites = intraabdominal free fluid, enlarged abdomen and slushing sounds Scaphoid = hollowed out, concave
In malnutrition, why is the abdomen swollen?
Loss of protein from intravascular compartment, changes oncotic pressure so fluid moves extravascular
If a patient presents with Jaundice, what would you expect to find in their history?
Drug/alcohol - erythromycin can predispose jaundice, cirrhosis from alcohol abuse
Bleeding problems (affects vit K clotting factors 7 9 10)
History blood transfusion
History foreign travel - place where jaundice endemic and no vax
History sexual promiscuity i.e. hepatitis
Pale stool/dark urine - obstructive jaundice
What are the physical signs of jaundice?
Yellowed sclera Scratch marks Liver flap/asterixis (ammonium based compounds not detoxified can affect NS) Nail beds (leukonikia -white nail) Spontaneous haemorrhage (bruising) Gynaecomastia (lack of oestrogen metabolism) Palmar erythema Ascites
What investigations can be done for a patient presenting with jaundice?
Stool/urine analysis
Blood tests (LFTs):
- AST and ALT - if raised then liver cells depleted
- gamma glutamyl transferase - for alcohol
- FBCs for macrocytic anaemias
Abdominal US
CT is possibility of cancer
When pain is due to inflammation e.g. appendicitis, peritonitis, when is:
a) Pain poorly localised in initial stages
b) Well localised when it spreads
a) sympathetic nervous system hard to tell which organ
b) supplied by somatic nerves
What is the pain like when a patient has an obstruction?
Comes in waves (apart from biliary colic which is constant)
What signs/symptoms are indicative of peritonitis?
Pain felt in area of inflammation, pain worse with movement, coughing, inspiration
Guarding/rigidity
Rebound tenderness - pain worse on withdrawal of hand
Percussion tenderness
Absent bowel sounds
What are the immediate investigations when someone presents with abdominal pain?
Urine testing - infection, trauma, pregnancy
FBCs - increased if appendicitis
U+E - kidney function
Amylase - pancreatitis
Pain x rays - erect CXRm supine AXR - can show obstructions or perforations
What is a laparoscopy? What is laparotomy?
Keyhole surgery in abdomen - CO2 in abdominal cavity to lift to see structures - if laparoscopic appendicectomy then removed
Open surgery with vertical midline scar
What is appendicitis caused by? What are its presenting symptoms?
Obstruction of lumen by faecolith (calcified faeces), inflammation of localised lymph tissue, carcinoma
Initial central colicky pain then localised to right iliac fossa, mild temperature, increased WBCs
What is mesenteric adenitis?
Enlargement of mesenteric lymph nodes in children/adolescents - often confused with appendicitis and associated with URTI, earache, sorethroat, high temp, tenderness and raised WBCs
What are the symptoms for a perforated peptic ulcer?
Sudden onset of pain in upper abdomen, central abdomen or upper left Q.
History of ulcers, reflux or heartburn
Rigid silent abdomen - generalised peritonitis
Absence of bowel signs
What is diverticular disease?
Large bowel develops pouches on sides of abdominal wall - usually left side of colon. From poor diet without fibre.
What are the 4 cardinal features of intestinal obstruction?
Pain, distension, vomiting, absolute constipation
If an older male C/O severe abdominal pain radiating into back or groin with a pulsatile mass in abdomen, what is the cause?
Ruptured aortic aneurysm (dilation of aorta >3cm) - fatal if untreated
