2.1. Gastric Disease - Helicobacter Pylori Infection Flashcards
What type of Bacteria is Helicobacter Pylori?
Gram Negative
What percentage of the Population are infected with this at some point?
50%
When is Helicobacter Pylori infection acquired?
In childhood
Where does Helicobacter Pylori colonize?
On the Surface of Gastric-type Mucosa
Does the Helicobacter Pylori infection penetrate the Epithelium?
No
Does the Helicobacter Pylori evoke an immune response?
Yes, even though it does not penetrate the Epithelium, an immune response still takes place
Where does the Immune Response to Helicobacter Pylori take place?
In the Underlying Mucosa
What is the Immune Response dependent on?
The Hosts Genetic Factors
What does the Immune Response cause?
- Chronic Gastritis
- Peptic Ulceration
- Gastric Cancer
What percentage of the Immune Response leads to Asymptomatic Chronic Gastritis?
80%
What percentage of the Immune Response leads to Chronic Atrophic Gastritis?
15-20%
What occurs with Chronic Atrophic Gastritis?
Intestinal Metaplasia
What percentage of the Immune Response leads to Peptic Ulceration?
15-20% - Continuation from Chronic Atrophic Gastritis
What percentage of the Immune Response to Helicobacter Pylori, leads to Gastric Cancer?
Less than 1%
What occurs with Gastric Cancer caused by Helicbacter Pylori?
Mucosa Associated Lymphoid Tissue (MALT)
What does Helicobacter Pylori release?
Urease
What is the action of Urease?
It breaks down Urea into:
- CO2
- Bicarbonate
- Ammonium
What does the Bicarbonate, released from the Urea, cause?
Localized increase in Gastric pH
What does the localised increase in Gastric pH stimulate?
The production of more Gastric Acid throughout the Stomach - which can cause damage to the Gastric Epithelial Cells
What are the Clinical Signs of Helicobacter Pylori infection?
- A raised White Cell Count
2. Inflammatory markers in the blood (CRP and ESR)
What symptoms will a person with a Helicobacter Pylori infection present with?
- None - 80% are asymptomatic
2. Symptoms dependent on how the Disease progresses
What investigations are needed for a Helicobacter Pylori infection?
- Upper G.I. Endoscopy with Biopsy
- Serology
- ELISA test
- Bacterial Cultures
- Urea Breath Test
What is the purpose of the Endoscopy with Biopsy?
- To visualize the inside of the Gastric Lumen
2. This should be taken for a Rapid Slide Urease Test (CLO)
What is the purpose of the Serology?
- To look for IgG produced in response to the infection
- To look for a raised WCC
- To look for inflammatory markers (CRP and ESR)
What is the purpose of the ELISA test?
This is stool antigen test is to look for the presence the associated antigens
What is the purpose of the Bacterial Culture?
To identify the infective organism
What is the purpose of the Urea Breath Test?
As the Ureas will break down Urea, ingestion of a radioactively marked Urea will show it being broken down and exhaled
What is the name of the Treatment of Helicobacter Pylori infection?
Eradication Therapy
What does Eradication Therapy consist of?
1 x Proton Pump Inhibitor
2 x Antibiotics
What Proton Pump Inhibitor is used?
Omeprazole
Which 2 Antibiotics are used?
- Clarithromycin
- Amoxicillin
(Tetracycline if allergic to Penicillin)
