GI tract disorders Flashcards
How does the oesophagus normally function (and what is the diagram that represents this)?
The upper oesophageal sphincter relaxes
Food enters and a peristaltic wave is triggered in the striated muscle
Lower oesophageal sphincter relaxes as swallow is initiated and food enters stomach
Seen below:
What are common oesophageal disorders?
Gastro-oesophageal reflux disease
Oesophageal motility disorders
Eosinophilic oesophagitis
Oesophageal cancer
What are different manifestations of GORD (gastro-oesophageal reflux disease)?
Oesophagitis
Barett’s oesophagus
Benign oesophageal stricture
What are symptoms of oesophageal disease?
COMMON
Dysphagia and odynophagia (difficulty and pain swallowing)
Heartburn
Acid regurgitation
Waterbrash
LESS COMMON
Chest pain
Food regurgitation
Food bolus obstruction
Cough
Altered voice- dysphonia
Globus (sensation of food being stuck but swallowing not affected)
Why can cough and altered voice in oesophageal disease?
Cough= when acid gets into respiratory system
Altered voice= irritated vocal chords
What are the different types of dysphagia?
What are the two main types of GORD (gastro-oesophageal reflux disease) and how are they different?
Transient lower relaxations= Usually acid is immediately cleared so no inflammation
Lower sphincter pressure decrease= inflammation due to chronic acid
What are the typical symptoms of GORD (gastro-oesophageal reflux disease)?
HEARTBURN= burning discomfort behind the breast bone spreading upwards
ACID REGURGITATION= often meal related or postural
WATERBRASH= hypersalivation secondary to gastro-oesophageal reflux
What are different investiagtions that can be done in oesophageal disease?
Endoscopy and biopsy
Barium swallow= x-ray after barium is swallowed.
Oesophageal function tests (Manometry, pH and Impedence monitoring)
CT, CT-PET scans or endoscopic ultrasound for tumours
What is a manometry test?
The manometry test senses the pressure and constriction of muscles in the esophagus as you swallow. It can detect patterns of muscle activity throughout the length of the esophagus, including contractions that are too weak or too powerful
What is impedence monitoring?
Esophageal 24-hour pH/impedance reflux monitoring measures the amount of reflux (both acidic and non-acidic) in your esophagus during a 24-hour period, and assesses whether your symptoms are correlated with the reflux.
What is oesopahgitis?
Inflammation of the oesophagus
Secondary to acid reflux
Can cause stricture
What is oesophageal stricture?
An esophageal stricture refers to the abnormal narrowing of the esophageal lumen; it often presents as dysphagia
What is Barrett’s oesophagus?
The squamous (oesophagus) is replaced by columnar (stomach) epithelium
Way for oesophagus to defend against large amounts of acid in chronic acid reflux
Often asymptomatic and commenest in obese men >50
If untreated can lead to adenocarcinomas
What is the treatment for Barrett’s oesophagus?
Barrets can be ablated (removed) so it does not become malignant. PPI are given long term (omeprazole ect)
What is the general treatment of gastro-intestinal reflux disease?
Lifestyle= smoking, alcohol, diet, weight
Mechanical= posture, elevate head in bed
Antacids
Acid supression= PPIs e.g. omeprazol, H2RA e.g. randitidine
Surgical- fundoplication (stomach wrapped around lower oesophagus)
What is an example of a oesophageal motility disorder?
Achalasia
What is achalasia and what does it present with?
Failure of the LOS relaxation together with absence of peristalsis
Degenerative lesion of oesophageal innervation
Typically presents in younger people with dysphagia to liquids and solids, weight loss, chest pain
What is the treatment for achalasia?
BoTox (paralyses LOS)
Endoscopic Dilatation
Surgical myotomy (surgeon cuts LOS)
POEM (Peroral endoscopic myotomy- cut without incision through skin)
What does achalasia look like on a barium swallow scan?
Dilated oesophagus, tight sphincter, ‘rat tail’
What is eosinophilic oesophagitis?
Eosinophilic esophagitis
is a chronic, immune/antigen-mediated esophageal inflammatory disease associated with esophageal dysfunction resulting from severe inflammation
What does eosinophilic oesoiphagitis present with?
Common presentation with Food bolus obstruction, dysphagia
Younger age, M>F, prevalence 50/100,000
History of atopy (asthma, hay fever)
What does an endoscopy of eosinophilic oesophagitis look like?
Endoscopy - furrows (lumps), rings, exudates, strictures
How is eosinophilic oesophagitis diagnosed?
Biopsy required for diagnosis
What is the treatment for eosinophilic oesophagitis?
Diet changes (eliminate egg, wheat, milk, nuts, soya, fish)
Drugs – PPI, topical sterois ( budesonide fluticazone known as jorvesa)
Dilatation – for strictures
What can cause oesophageal stricture?
GORD
Barett’s
Extrinsic compression (lung tumour)
Corrosive (ingestion)
Oesophageal cancer
Post-radiotherapy
What is the treatment for oesophageal stricture?
Proton pump inhibitors if it is caused by inflammation
Treatment of cancer
Push and balloon dilators
What are the different types of oesophageal cancer?
Adenocarcinoma- lower 1/3
Squamous cell carcinoma- mid and upper oesophagus
What is the staging of oesophageal cancer?
Use TNM classification ( T=tumour N=Nodes M= metastases)
What is the treatment of oesophageal cancer?
Sugery
Chemotherapy
Radiotherapy
Targed therapy/ immunotherapy
Palliation- symptom management
What is pharyngeal pouch?
PP= pouch just before the cricopharynheous, patients eats, the pouch fills and the patient experiances dysphasia then the pouch is emptied and food from previous days brought up
What is the first thoughts of younger and older patients presenting woith dysphagia?
In the elderly think of neurological causes particularly if intermittent / long standing or sinister causes (oesophageal Ca) if new, progressive with regurgitation and weight loss.
Oesophageal Ca presents with progressive dysphagia for solids first then liquids.
In the younger think of dysmotility (achalasia, or 2ndary to acid reflux,).
In dysmotility syndromes dysphagia for liquids is as bad as for solids.
Young patients with food bolus obstruction: think of eosinophilic oesophagitis.
What does tarry black stool indicate?
Chronic blood loss in the GI tract
What drugs can cause bad stomach ulcers?
Aspirin or NSAIDs
What is Helicobacter Pylori?
Bacterium that resides in stomach
Interferes with acid secretion and alters the lining of stomach. End result is ulceration
Helicobacter utilises UREA and interacts with it. Splits it into bicarb and ammonia, bicarb neutralises acid- how is survives
What is the diagnosis of H. pylori?
Breath test
Antibody test- only IgG so cannot tell if currently have infection
Stool antigen test
Culture
Histology
CLO test
What is a CLO test?
CLO test= petri dish containing ammonia where a biopsy is placed. If H. pylori is present it will split the urea and petri dish will become alkaline and can be tested with pH paper
What is the breath test in diagnosis of H. pylori?
Radiolabeled urea can also be drank (C13), splits urea and this will be exhaled as radiolabeled CO2 and if there is any radioactivity this will be proportional to Hp in stomach
What is maldigestion and malabsorption?
Maldigestion= Impaired breakdown of nutrients in the lumenal phase
Malabsorption= defective mucosal uptake and transport of adequately digested nutrients
What is the term for diseases that cause both maldigestion and malabsoption?
Malassimilation
Where are the 3 areas that malabsorption can occur?
Luminal phase of absorption
Mucosal phase of absorption
‘Post mucosal’ phase of absorption
What can cause enzyme problems that leads to malabsoption?
Enzyme deficiency: pancreatic insufficiency
Enzyme inactivation: ZE syndrome
Inadequacy of mixing: rapid transit, surgical resection (remove part of GI)
What bile salt problems can cause malabsorption?
Decreased bile salts: cholestasis, cirrhosis
Bile salt deconjugation: bacterial overgrowth
Bile salt loss: ileal disease or resection
What problems can occur in the luminal stage of digestion that causes malabsorption?
Enzyme problems
Bile salt problems
Bacterial overgrowth- competes for food
B12 deficiency
What problems can occur in the mucosal stage of digestion that causes malabsorption?
Brush border hydrolysis: lactase deficiency (post gastroenteritis, alcohol, radiation)
Epithelial transport:
Reduced absorptive surface - resection
Damaged absorptive surface – coeliac disease, tropical sprue, Crohn’s disease, ischaemia
Infections – Giardia, SIBO
Infiltration – lymphoma, amyloid
What problems can occur in the post- mucosal stage of digestion that causes malabsorption?
Lymphatic obstruction (lymphangectasia, neoplastic, TB) that prevents transport of fat through lympthatics
What are the clinical features of malabsoption in general?
Diarrhoea and weight loss despite adequate intake
Bloating, distension, cramps and borborygmi (excess noise)
Lethary or malaise
Symptoms often mild and non specific
What are the symptoms of malabsorption syndrome?
Steatorrhoea (pale, oily stools that float), distention, weight loss, oedema
RARE presentation
What is intestinal ‘angina’?
After a meal get abdominal pain
What clues on examination will you get of someone who is malabsorbed?
Evidence of malnutrition
Cracking of skin around mouth (angular cheilitis) inflammation of tongue (glossitis), oedma, rash, psychosis, dementia, ataxia and neuropathy
What neurological symptoms will you see in someone who is B12 deficient?
Peripheral neuropathy
Ataxia- balance, coordination, speech
Psychosis, dementia
What is the rash called often seen in coeliac disease?
Dermatitis herpetiformis
What can happen to red blood cells in malabsorption?
Microcytosis- iron deficiency (coeliac)
Macrocytosis- B12 and folate deficiency but also in coeliac and alcohol
What are the 3 main causes of malabsorption?
Coeliac disease
Pancreatic insufficiency
Small bowel bacterial overgrowth (SIBO)
What main test is used to diagnose coeliac disease?
Tissue transglutaminase (TTG) antibody test
Or a small intestinal biopsy if antibody levels not high enough
What main test is used to diagnose pancreatic insufficiency?
Faecal elastase - Enzyme measure in stool
What main test is used to diagnose SIBO?
Quantitative culture of jejunal fluid is the gold standard (> 105/mL is abnormal)
Glucose/Hydrogen breath test more practical
Small bowel radiology to look for anatomical abnormalities
What are the 3 main features of coeliac disease?
- Mucosal inflammation
- Villous atrophy
- Crypt hyperplasia
Which occur upon exposure to dietary gluten and which demonstrate improvement after withdrawal of gluten from the diet.
What causes coeliac disease?
Gentic predisposition- need specific HLA
Exposure to gluten as well as triggering event (immunological challenge e.g. illness, pregnancy)
This results in gliaden reactive T lymphocytes and an autoimmune attack on the intestine
What changes in a microscopic view of villi in coeliac disease?
Villi lost, crypts are longer and epithelium lining full of inflammatory cells
What are the symptoms of coeliac disease?
Diarrhoea
Anaemia
Dyspepsia (indigestion)
Abdominal pain and bloating
Weight loss
Mouth ulcers
Fatigue
Children- short stature, delayed puberty
Osteomalacia
What clues on investigation would link to coeliac disease?
Anaemia
Iron and folate deficiency
Low calcium and elevated alkaline phosphatase (metastatic bone disease)
What diseases does coeliac disease cause?
Osteoporosis
Infertility
Dermatitis herpetiformins (rash)
Lymphoma
Ulcerative jejunitis
What is the treatment for coeliac disease?
Gluten free diet (life long)
Nutritional supplements
Screen for complications (e.g. bone disease
Very rarely is immunosupressant medication
What is pancreatic exocrine insufficiency and what are the symptoms of it?
Any disease of exocrine pancreas in theory can lead to this- lack of production of bicarbonate and enzyme-rich fluid
Symptoms do not occur until disease has progressed (90%) of function lost
Steatorrhoea, weight loss, vitamin deficiency (A,D,E,K)
What are the main causes of pancreatic exocrine insufficiency?
Chronic pancreatitis (alcohol)
Pancreatic cancer
Cystic fibrosis
Haemochromatosis
Pancreatic or gastric resection
What is haemochromatosis?
Abnormal Fe deposits in liver/pancreas
What can cause chronic pancreatitis?
Alcohol
Duct obstruction – tumours, stones
Cystic fibrosis, other genetic causes
Systemic disease eg lupus
Autoimmune pancreatitis
All can lead to pancreatic exocrine insuffiency
How is pancreatic endocrine insufficiency diagnosed?
Symptoms
Pancreatic imaging (CT, MRI)
Tests- faecal elastase, secretin stimulation tests
What is the treatment for PEI?
Pancreatic enzyme replacement- taken with meals and snacks
Gastric acid suppression and vitamin supplements
What is small intestinal bacterial overgrowth?
Bacteria from colon moves up and grows the in the small intestine. Competes with you for food and ferments food higher in the GI tract
Loss of balance between gram - and +
What are the causes of bacterial overgrowth?
STASIS
- strictures- Crohn’s disease or TB
- hypomolitity- old age, opiates, diabetes
BLIND LOOPS
- surgery
What are blind loops?
Seen in patients with surgical change of GI
The part of loop where food not passing through= stagnant overgrowth
What are the consequences of small bowel bacterial overgrowth?
Vit B12 malabsorption (bacteria competes for it)
Bile acid deconjugation
Intraluminal protein utilisation
Brush border damage
Ulceration of mucosa
Bowel dysmotility
What is the glucose/ H2 breath test?
Human cells do not produce hydrogen therefore any H2 in breath is coming from bacteria. Drink glucose drink and if there is abnormal numbers of bacteria in small intestine H2 will rise
What is the treatment of SIBO?
Treatment with 2 weeks of antibiotics e.g. tetracycline, ciprofloxacin, rifaximin
What can impair bile acid reabsorption?
Ileal disease or resection
Post-cholecystectomy
Rapid transit
Coeliac, SIBO, chronic pancreatitis
What is giardia lamblia?
Non-invasive pathogen
Causes malabsorption- brush border damage and bile acid utilisation
What is Whipple’s disease?
Uncommon bacterial infection
Presents with diarrhoea, arthritis, fever, cough, headache, muscle weakness
Antibiotic therapy for months to years.
What is the screening test done for colorectal cancer?
The Quantitative Faecal ImmunochemicalTest(qFIT) is atestto detect hidden or ‘occult’ blood in stool samples. qFIT testuses antibodies and can quantify the level of blood in stools
What is a polyp?
A polyp is a projecting growth of tissue from a surface in the body, usually a mucous membrane. Polyps can develop in the: colon and rectum.
Polypoid lesion on a stalk, projecting into the lumen of the colon
What medications pre-dispose a polyp to bleeding?
Blood thining medication e.g. aspirin
What are the different features of this polyp?
A= dysplastic (abnormal) glands forming tubular and villous structures- adenoma
B= Abnormal gland that is invading the wall of the colon and the glandular appearance a lot more disorganised- started becoming malignant- adenocarcinoma
What histological features of a polyp would indicate an adenocarcimona?
High nucleus: cytoplasm ratio (for proliferatiuon)
Hyperchromasia= increased staining, production of nuclear material
Pleomorphism= differences in size and shape between cells
What are the red and blue parts of this polyp?
Adenoma circled in blue; adenocarcinoma circled in red
What are the different types of colonic polyp and do they have malignant potential?
Adenomas have the highest progression potential to adenocarcinoma
Hyperplastic ( metaplastic) polyps don’t have malignant potential. These are small lumps that are essentially projections of normal lining
A special type of hyperplastic polyp called serrated polyp has some malignant potential. These are flat and difficult to remove
What is the adenoma-carcinoma sequence?
Theadenoma-carcinoma sequencerefers to a stepwise pattern of mutational activation of oncogenes (e.g.K-ras) and inactivation oftumour suppressor genes(e.g.p53) that results in cancer.
Anoncogeneis a gene that has the potential to cause cancer. In tumour cells, these are often mutated or expressed at high levels.
A tumour suppressor gene is a gene that is involved in dampening the cell cycle or promotion of apoptosis or both. Examples include inactivation ofp53.
Deletion of the APC gene (suppressor) predisposes to cancer.
What is the timeframe for normal epithelium to progress into cancer?
Takes many decades for early adenomas to occur
Once these are present it can take 4-10 years to develop into a cancer
What are alarm features that suggest colorectal cancer?
Rectal bleeding
Anaemia or thrombocytosis (high platelet count)
Persistant diarrhoea with frequent noctural symptoms
Weigh loss
New onset on symptoma > 50 years
Family history of bowel cancer or past medical history of IBD
What is the difference between grading and staging of cancer?
GRADE The grade of a cancer is based on how the patterns of cancer cells look under a microscope: normal (or differentiated) or abnormal. Higher grade tumors tend to grow and spread faster than lower grade tumors. SHOWS POTENTIAL FOR GROWTH
STAGE The stage of colorectal cancer is a standard way for doctors to sum up how far the cancer has spread. SHOWS EXTEND OF GROWTH
What is the TNM staging system for cancer?
T refers to how far the primary tumor has grown into the wall of the nearby organs.
N refers to cancer spread to nearby lymph nodes.
M indicates whether the cancer has metastasized (spread to distant organs).
What constitutes a T1-4 stage for cancer?
1= mucosa, 2= muscle, 3= serosa and 4= nearby organs
What are risk factors for colorectal cancer?
A diet high in redmeatsand processedmeats and low in fibre
Cookingmeatsat very high temperatures (frying, broiling, or grilling)
Obesity, physical inactivity, smoking, alcohol excess
Older age
Family history of colorectal cancer/ polyps
History of IBD
Where are the most common sites of colorectal cancer?
50% occurin rectum and sigmoid colon
Caecum and ascending colon also important
Who is screened for colorectal cancer?
Population > 50 years every 2 years via a stool sample taken at home
If at risk- colonoscopy every 5 years from the age of 45
What is a functional gastrointestinal disorder?
Functional gastrointestinal disorders (FGID) are a group of disorders characterised by chronic gastrointestinal (GI) symptoms (eg abdominal pain, dysphagia, dyspepsia, diarrhoea, constipation and bloating) in the absence of demonstrable pathology on conventional testing.
Associated with the motility of the gut. There is significant brain-gut interaction that leads to the symptoms