Helicobacter Pylori (H. Pylori)

What sample is needed for Helicobacter Pylori?

1. It is performed on the patient’s serum using techniques such as ELISA.
2. H. pylori can be diagnosed with a duodenal biopsy.
3. The H. pylori sample can be cultured.
4. Various samples available are:
5. Serum, for specific antibodies. This is a non-invasive method and easy to perform. This antibody appears 2 months after infection and remains elevated for over a year after treatment.
   1. Initially, IgM is formed, followed by IgG and IgA. These are found in the blood and the mucosa and are of high titer in chronic cases.
   2. Types of antibodies:
      1. IgG – anti-H. pylori
      2. IgA – anti- H. pylori.
      3. IgM – anti-H. pylori
6. Biopsy:
   1. These bacteria can be seen in the gastric mucosal biopsy. (Giemsa stain shows these bacteria). This is a more specific and confirmatory test.
7. Culture:
   1. A mucus sample can be obtained via a gastroscope for culture.
8. Rapid urease test:
   1. For this test, the sample can be gastric mucosa or gastric mucus.
9. Breath test:
   1.  This detects gastric urease and measures CO2 in the breath. The patient needs to be at rest for this test.
10. The stool examination:
    1. The stool is examined for the H. Pylori antigen. Try to do the test on a fresh sample.

What are the precautions taken for Helicobacter Pylori?

1. For culture:
   1. Stop antibiotics.
   2. Antacids.
   3. Bismuth therapy 5 to 14 days before the procedure.

What are the Indications for Helicobacter Pylori?

1. These tests are used to diagnose H. Pylori infection.
2. In the patient with chronic gastric or duodenal ulcers.

How will you define Helicobacter Pylori?

1. Helicobacter Pylori was formerly called Campylobacter pylori or pyloridis.
2. It is S-shaped, curved, “gull-winged” like Campylobacter.
3. It is a gram-negative bacillus found in the mucus covering the gastric mucosa.
4. It lies next to the gastric lining epithelial cells and the gastric pits.

 How will you discuss the bacteriology of Helicobacter pylori?

1. This is a small, gram-negative, spiral, rod-shaped bacterium discovered in 1982.
2. Helicobacter pylori (H. pylori) was formerly known as Campylobacter pylori.
3. These are strongly urease-positive.
4. Gram-negative spiral-shaped rods.
5. It has a feature in common with Campylobacter.
6. It has multiple flagella at one pole and is actively motile.
7. H. Pylori growth takes 3 to 6 days when grown at 37 °C in a microaerophilic atmosphere.
8. Culture media used are:
   1. Skirrow medium.
   2.  Can add vancomycin, polymyxin B, and trimethoprim.
   3. Chocolate medium and selective media with antibiotics.
9. The colonies are translucent and measure 1 to 2 mm in diameter.
   1. These colonies have characteristic morphology.
   2. H. pylori is oxidase-positive and catalase-positive.
   3. Bacteria are motile and strong urease producers.

How will you summarize the bacteriology of Helicobacter pylori (H. pylori)?

What are the complications and associations of Helicobacter Pylori (H. pylori) infection?

1. This bacterium causes gastritis, gastric, and duodenal ulcers.
   1. This may even cause an oesophageal ulcer.
2. This bacterium is also associated with gastric carcinoma.
3. H. pylori is lying in the mucous of the gastric mucosa.
4. This bacterium is seen in various conditions:
5.  It is found in the antrum of the stomach in acute and chronic gastritis and is positive in 90% of patients with duodenal ulcers.
   1. 95% to 98% of the patients with a duodenal ulcer (another reference says 100%).
   2. 70%  (70% to 75%) positive in gastric ulcers.
   3. This is also seen in gastric ulcers in 60% to 70% of patients.
   4. 20% to 25% of patients with gastric cancer are positive for H.Pylori.
   5. 10% of healthy people in the younger age group, around 30 years old, are positive for H. pylori.
6. It is positive in 50% of the cases with non-ulcer dyspepsia.
7. The positivity of H. pylori increases with increasing age.
8. Gastric colonization by H. pylori increases with age.
9. Most of the people with H. Pylori colonization are asymptomatic.
10. Helicobacter pylori antibodies are found in 20% to 25% of healthy US citizens.
11. It shows that Helicobacter Pylori infection is subclinical.

How will you discuss the pathophysiology of Helicobacter Pylori (H. pylori) infection?

1. H. Pylori growth has an optimum pH of 6.0 to 7.0 and would be killed, or it can not grow at a pH within the gastric lumen.
2. Gastric mucus is impermeable to acid and acts as a buffer system.
3. H. Pylori produces a protease enzyme that modifies gastric mucus and reduces the acid’s ability to diffuse through it.
4. H. Pylori produces urease activity, leading to NH3 production and further acid buffering.
5. H. Pylori was given to volunteers; later on, it was found that those people developed gastritis and hypochlorhydria.
6. When antibiotics were given to these patients, they found improvement in gastritis and duodenal ulcers.
7. Toxins and lipopolysaccharides may damage mucosal cells, while NH3 can directly damage epithelial cells.
8. Microscopic findings are:
   1. Gastritis is characterized by the infiltration of chronic and acute inflammatory cells.
   2. Neutrophils and mononuclear phagocytic cells are seen within the epithelium and lamina propria.
   3. There are vacuoles in the epithelial cells.
   4. The epithelium is damaged.
   5. There is glandular atrophy.

How will you discuss the pathogenesis of Ulcer due to Helicobacter Pylori (H. pylori)?

1. These bacteria enter the body and damage the stomach lining.
2. The stomach mucus protects the mucosa from acid (HCl).
3. When these bacteria damage the mucosa, acid can pass through the lining, leading to ulcer formation.
4. These bacteria may be dormant, and the patient may be asymptomatic.

What is the mode of the spread of Helicobacter Pylori?

1. Its transmission is from person to person.
2. These bacteria can enter the body from:
   1. Food.
   2. Water.
   3. Utensils.
   4. Saliva and body fluids through close contact.

How will you discuss the clinical presentation of Helicobacter Pylori infection?

1. The incidence of H. pylori is age-related.

2. H. pylori is associated to a lesser degree with focal areas of gastritis in the body of the stomach.
3. In the case of acute infection:
   1. There may be nausea and abdominal pain.
   2. These S/S may last for many days.
   3. Histologically, there is gastritis with neutrophil infiltration.
4. The above stage may go into a chronic stage.
   1. There is diffuse mucosal involvement (chronic gastritis).
   2. There is the infiltration of neutrophils and lymphocytes.
   3. Chronic H. pylori infection with gastritis may be seen in 30% to 50% of patients, which may be asymptomatic.
5. Chronic or recurrent duodenal ulcer is associated with excessive acid production and the presence of Helicobacter pylori.
   1. In the case of Zollinger-Ellison syndrome, duodenal ulcers and H. pylori infection are almost negative.

How will you discuss the pattern of H. pylori infection?

What is the outcome of Chronic H. Pylori infection?

1. 10% develop a duodenal or gastric ulcer.
2. 0.1 to 3% develop gastric cancer.
3. 0.01% develop B-lymphocyte lymphoma called MALT (mucosa-associated lymphoid tissue lymphoma).

What is the normal value of Helicobacter Pylori (H. pylori) infection antibodies?

H. pylori antibody

• The negative antibody test result from Eliza indicates there is no infection.
• The positive antibody test indicates the IgG-H-Pylori antibody in serum.

How will you diagnose Helicobacter Pylori?

1. Endoscopic biopsy for culture of the tissue:
   1. The gold standard for diagnosis is the endoscopic gastric mucosa biopsy for culture.
   2. This biopsy is placed in 2 to 3 mL of isotonic saline.
   3. It is plated on enriched media (chocolate agar or selective media, Skirrow’s).
   4. It is then incubated for 5 to 7 days at 37 °C.
   5. 75% of cases are positive for culture.
   6. If you do a Giemsa stain on the biopsy, you will detect 90% of the cases.
   7. The Warthin-Starry silver stain yields better results than the Gram stain and the Giemsa stain.
   8. Culture takes several weeks to reach the final result.
   9. Disadvantages:
      1. It is invasive and expensive.
      2. More than 2 samples are needed for better sensitivity.
2. Rapid Urease test:
   1. This bacteria produces a urease enzyme that acts on urea. This makes the basis for other tests. This can be done by:
      1. Gastric mucosa tissue.
      2. The gastric mucosa is placed on the paper, and its color will change.
      3. The special tablet is placed in the test tube, and gastric mucosa is added.
      4. Specificity and sensitivity = 90%/>90%
3. The breath test:
   1. It is noninvasive because H. pylori can produce CO2 by the urease enzyme acting on urea.
   2. The patient is given radiolabel Carbon-13 or carbon-14. It is given orally.
   3. Then, expired air is tested for radioactivity 20 to 120 minutes later.
   4. This test sensitivity is >95%, and specificity is also >95%.
   5. This test is considered the gold standard test, not the culture.
4. Serology:
   1. Specificity and sensitivity = >90%.
   2. These tests of the Helicobacter Pylori (antibody test) are:
   3. The anti-IgG H. pylori are most commonly used.
      1. Its level rises after two months of infection and remains raised for a year after the treatment.
   4. The anti-IgM rises first in about 3 to 4 weeks after the infection.
      1. It disappears in 2 to 3 months after the treatment.
   5. IgM and IgA antibody levels fall after the treatment in about 4 weeks.
      1. While IgG level is not affected by the treatment.

5. By ELIZA: Antibodies are positive in almost 100% of the duodenal ulcer.
   5. 80% in gastric ulcers.
   6. Positivity increases with increasing age.
   7. Positive results do not confirm the diagnosis, but negative results rule out H. pylori infection.
6. H. pylori antigen:
   5. It is done on a fresh stool.

What are the causes of a positive breath test for H. pylori?

1. Acute and chronic gastritis.
2. Gastric ulcer.
3. Recurrent duodenal ulcer.
4. Carcinoma of the stomach.

What is the outcome of H. Pylori infection?

What are the common tests for the diagnosis of H. Pylori infection?

How will you treat Helicobacter Pylori infection?

1. Usually, a gastroenterologist advises the tripple regime.
   1. Most clinicians advised Amoxicillin, clarithromycin, and PPI.
   2. Some advised clarithromycin, metronidazole, and tinidazole.
   3. In addition, proton pump inhibitors and H2 blockers are advised.
2. Avoid non-steroidal anti-inflammatory drugs.

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