Treatment of peptic ulceration and Inflammatory Bowel disease Flashcards
(75 cards)
1
Q
What are gastric acid secretions required for?
A
- Digestion of food
- Iron absorption
- Killing pathogens
2
Q
What are the protective mechansims against gastric acid?
A
Mucous secreting cells - Trap bicarbonate ions (alkaline) - Creates gel like barrier - Important protective layer Prostaglandins locally produced - Stimulates secretion of mucus and bicarbonate - Dilate mucosal blood vessels - Cytoprotective
3
Q
How much gastric juice is produced per day?
A
2.5L
4
Q
What are proenzymes e.g. prorennin and pepsinogen produced by?
A
Chief / peptic cells
5
Q
What cells produce HCL and intrinsic factor
A
Oxyntic / parietal cells
6
Q
What is intrinsic factor?
A
a substance secreted by the stomach which enables the body to absorb vitamin B12. It is a glycoprotein.
7
Q
What does the production of HCl involve?
A
Proton pump (K+H+ATPase)
8
Q
What does inhibition of the proton pump result in?
A
Less HCl being secreted by cheif cells therefore increased pH
9
Q
What are the 3 endogenous secretagogues? (3 substances which increase HCl production)
A
- Gastrin
- Acetylcholine
- Histamine
10
Q
What is gastrin produced by?
A
Gastrin cells (G cells)
11
Q
What kind of substance is gastrin?
A
Polypeptide hormone
12
Q
Where are gastrin cells located?
A
Gastric antrum and duodenum
13
Q
What have a strong effect on the G cells?
A
Proteins in food
14
Q
How does gastrin work?
A
- Secreted by G cells into blood
- Stimulates secretion of acid by parietal cells (thro the proton pump)
- Also increases pepsinogen secretion - stimulates blood flow and increases gastric motility
15
Q
How does acetylcholine increase gastric acidity?
A
- Released from neurons to stimulate muscarinic receptors on surface of parietal cells and histamine containing cells
16
Q
What does histamine act on to increase gastric acidity?
A
- Parietal cell H2 receptors
17
Q
What cells release histamine?
A
- Mast cells lying close to parietal cell
18
Q
What substances increase histamine release?
A
- Gastrin
- Acetylcholine
19
Q
How does Helicobacter pylori damage the stomach?
A
- Damages mucosal barrier
- Creates inbalance between protective and destructive factors
20
Q
What percentage of the population are infected in Helicobacter pylori?
A
Roughly 50% (30% in UK)
21
Q
Where can peptic ulcers be found?
A
- Stomach or duodenum
- Gastric and duodenal ulcers = peptic ulcers
22
Q
What can H pylori infection increase the chances of?
A
- Gastric cancer (adenocarcinoma)
- Strong link with MALT (Mucosa Associated Lymphoid Tissue) Lymphoma
- GORD, Dyspepsia, Atrophic gastritis, iron deficiency anaemia, idiopathic thrombocytopenic Purpura
23
Q
What is dyspepsia?
A
Indegestion
24
Q
What is the clinical name for bad breath?
A
Halitosis
25
What symptoms can an H pylori infection present with?
- Nausea
- Dyspepsia
- Malaise
- Halitosis
Acute infection lasts about 2 weeks
26
What happens to the mucosa as a result of H pylori infection?
- Gastric mucosa becomes inflammed with neutrophils and inflammatory cells with marked persistant lymphocyte penetration
27
What does the outcome of H pylori infection depend on?
- Pattern of inflammation
- Host response
- Bacterial virulence
- Enviromental factors
- Patient age
28
What does a h pylori chronic infection result in?
Local inflammation and gastritis
29
What are the tests used to diagnose H pylori infection?
- Urea breath test
- Stool antigen
- CLO test (rapid urease test)
30
What test would be used to diagnose H pylori infection in primary care?
- Urease breath test or stool antigen test as they are non-invasive
- Stool antigen test cannot be undertaken to check eradication
31
WHat is the problem associated with stool antigen test for diagnosing H pylori?
Antigen will stay positive even if infection cleared (n
32
What test can be done simulatneously with an endoscopy?
- Biopsy based diagnostic test: Rapid urease test CLO test
33
What does the urea breath test really test for?
- Isotope labelled carbon dioxide
- Fromed from C-urea which is broken down by Urease (produced by H pylori) into the NH3 and isotope labelled carbon dioxide
34
What should patients who test positive for H pylori be treated with? (non-penicillin allergic)
- 7-day, twice-daily course of treatment with:
- PPI
- Amoxicillin
- Clarithromycin or Metronidazole
35
Name some proton pump inhibitors used for the first-line treatment of H pylori infection
- Esomeprazole
- Lansoprazole (common)
- Omeprazole (common)
- Pantoprazole
- Rabeprazole
36
What diseases can Proton pump inhibitors be used to treat?
- Peptic ulcer disease
- Dyspepsia
- GORD
- Treatment and prevention of NSAID associated ulcers
- Reflux oesophagitis
- Zollinger-Ellison syndrome
37
How does omeprazole work?
- Inhibits K+H+ATPase irreversibly (proton pump)
- Basal and simulated gastric acid secretion reduced
- Drug is weak base and accumulates in acid environment of the canaliculi of the stimulated parietal cell
- Usually oral administration
38
What are the unwanted side-effects and cautions of ppis?
- Relatively uncommon
- Headaches
- Diarrhoea
- Rashes
- Dizziness
- Somnolence
- Confusion
- Impotence
- Gynaecomastia
- Pain in muscles / joints
- Caution in:
- Liver disease
- Pregnancy
- Breast feeding
- May mask the symptoms of gastric cancer
39
Give some examples of Histamine H2 Receptor Antagonists?
- Ranitidine
| - Cimetidine
40
What are Histamine H2 Receptor Antagonists used to treat?
- Peptic ulcers
| - Reflux oesophagitis
41
What do Histamine H2 Receptor Antagonists inhibit?
- Histamine
- Gastrin
- Ach stimulated acid production
- Pepsin secretion also falls with reduction in volume of gastric juice
42
What are some of the differences between Ranitidine and Cimetidine?
```
- Bioavailability
Ranitidine ~ 50%
Cimetidine > 60%
- Half-life (renal excretion)
Ranitidine 2.5 hrs
Cimetidine 2 hrs
```
43
What drugs which reduce gastric acid secretions can be bought over the counter?
Histamine H2 Receptor Antagonists
44
What is the better tolerated Histamine H2 Receptor Antagonist Ranitidine or Cimetidine?
Ranitidine
45
What are the side-effects of Histamine H2 Receptor Antagonists?
```
Rare
- Diarrhoea
- Dizziness
- Muscle pains
- Alopecia
- Transient rashes
- Hypergastrinaemia
Can mask symptoms of gastric cancer
```
46
What are some of the unwanted side-effects specific to Cimetidine and why is this?
```
- Can interact with androgen receptors
Gynaecomastia
Decreased sexual function
- Inhibits cytochrome P450
Slows metabolism (and potentiates action) of range of drugs e.g oral anticoagulants and tricyclics
- Confusion in elderly
```
47
What differntiates dyspepsia from GORD?
- Dyspepsia = pain or discomfort centered in upper abdomen exac by food
- GORD = acid reflux, assoc with waterbrash
48
What is waterbrash?
A sudden flow of saliva (watery acidic taste) associated with indegestion
49
How is dyspepsia and GORD treated in adults?
- Stop NSAIDs where applicable
- OTC Remedies e.g antacids, Alignates and Simeticone
- Consider PPI for symptomatic treatment
- H2 receptor antagonist potential alternative
- Consider H pylori testing -> treat if positive
50
What are antacids?
- OTC medication used to treat Dyspepsia + GORD
- Directly neutralise acid + inhibit the activity of peptic enzymes
- Salts of magnesium and aluminium (gaviscon, alka-seltzer)
51
What are Alignates?
- OTC medication used to treat GORD + dyspepsia
| - Increase viscosity and adherence of mucus to oesophageal mucosa
52
What is Simeticone?
Antifoaming agent (helps bloating, flautulence)
53
What are the mucosal-damaging factors?
- Acid
| - Pepsin
54
What are the mucosal-protecting factors?
- Mucus
- Bicarbonate
- Prostaglandins
- Nitric oxide
55
What simply can be used to treat dyspepsia and GORD in the absence of red flag symptoms?
Dietary and lifestyle advice
56
How are peptic ulcers treated when H pylori positive?
Offer H pylori eradication if peptic ulcer disease and H pylori +ve
57
How are NSAID associated peptic ulcers treated?
Stop the use of NSAIDs where possible. Offer full-dose PPI or H2RA therapy for 8 weeks and, if H pylori is present, subsequently offer eradication therapy
58
How is peptic ulcer disease treated when H pylori negative; no NSAID?
Offer full-dose PPI or H2RA therapy for 4 - 8 weeks
59
What do PPIs usually end in?
-prazole
60
What do H2 Receptor Antagonists usually end in?
-idine
61
When should a repeat endoscopy be done?
- 6 - 8 wks later depending on size of lesion
| - Perform re-testing for H pylori using carbon-13 urea breath test if no peptic ulcer
62
What should be done with an individual with an unhealed ulcer?
- Exclude non-adherence, malignancy, failure to detect H pylor, inadverent NSAID use, other ulcer-inducing medication and rare causes such as Zollinger-Ellison syndrome or Crohn's disease
63
What should be done if symptoms continue to recur after peptic ulcer treatment?
- Offer a PPI to be taken at the lowest possible dose to control symptoms
- Discuss using the treatment on an as-needed basis with people to manage own symptoms
64
What is Zollinger-Ellison syndrome?
a condition in which a gastrin-secreting tumour or hyperplasia of the islet cells in the pancreas causes overproduction of gastric acid, resulting in recurrent peptic ulcers
65
What are the 2 types of Inflammatory Bowel Disease?
- Ulcerative colitis
| - Crohn's disease
66
Where does Ulcerative colitis affect?
Colon and rectum, inner lining
67
Where can Crohn's disease affect?
Any part of GI tract, through whole wall
68
How prevelant is UC and Crohn's in the UK?
- UC: 1 in 400
| - Crohn's: 1 in 700
69
What is the age of onset usually of UC and Crohn's?
Peaks at 15-30 and 50-70
70
What are the symptoms of IBDs?
- Abdo pain
- Diarrhoea
- PR blood
- Weight loss
- Systemic upset
- Ulcers
- Fever
Very variable prognosis
71
What kind of lesions are usually present in Crohn's disease?
Skip lesions
72
What can the complications of IBDs be?
- Stoma
- Anaemia
- Perforation
- Obstruction/stricture
- Fistulae
- Toxic megacolon
- malnutrition
- Increased risk of bowel cancer
73
What tests would be carried out to test for IBD?
- FBC, CRP
- Stool MCS
- Faecal calprotectin
- CT scan/MRI
- Endoscopy (sigmoidoscopy, colonoscopy) + biopsies
74
What can differentiate IBS from IBD?
IBS does not have any inflammatory markers
75
What are the treatments availabke for IBDs?
- Aminosalicylates e.g. mesalazine
- DMARDS e.g azathioprine, methotrexate decrease immune response
- Biologics e.g inflixamab
- Corticosteroids
- Symptomatic relievers (analgesics, lazxatives, "constipators")
- Surgery
