Antibiotyping and Prevalence of Virulent Genotypes Among Helicobacter Pylori and Their Impact on Response to Therapy

Summary

* Detection of primary antimicrobial susceptibility and resistance of Helicobacter Pylori infection.
* Detection of resistance and virulence genes of Helicobacter Pylori infection.
* Assessment of H pylori carcinogenicity gene.
* Evaluation of outcome and efficacy of antibiotics regimen will be used in our research.
* Evaluation of effect of other factors as diet (fatty and spicy meal), drugs as NSAIDs use, antibiotics for any cause on response of H pylori to antibiotics regimen.

Conditions

• H Pylori Infection

Interventions

GENETIC

detection of vacuolating cytotoxin A (Vac A) and cytotoxin-associated gene A (Cag A) virulent H.Pylori genotypes by polymerase chain reaction amplification(PCR) in gastric biopsies :

Extraction of DNA, using Wizard® Genomic DNA Purification Kit (Promega-USA), will be done following the manufacturer instructions. For detection of vacuolating cytotoxin A and cytotoxin-associated gene A gene, polymerase chain reaction amplification will be performed with a 9 minutes' initial denaturation at 94˚C, followed by 35 cycles of 1 minute at 94˚C, 45 seconds at 60˚C, and 45 seconds at 72˚C. Final extension will be performed for 5 minutes at 72˚C. For detection of vacuolating cytotoxin A (S1/S2, m1, m2), PCR will be performed with a 9 minutes' initial denaturation at 94˚C, followed by 35 cycles of 1 minute at 94˚C, 45 seconds at 56˚C, and 45 seconds at 72˚C. Final extension will be performed for 5 minutes at 72˚C. Amplified DNA will be analyzed by agarose gel electrophoresis. A positive sample will give bands at DNA fragment 138-bp for cytotoxin-associated gene A, at 259/286-bp for vacuolating cytotoxin A s1/s2, and 290-bp and 352-bp for m1 \& m2, respectively

DIAGNOSTIC_TEST

Culture and sensitivity of endoscopic gastric biopsies:

During endoscopy, three biopsies will be taken from antrum and/or corpus of and will be examined by rapid urease test also known as Campylobacter-like organism test (Kimberly-Clark,USA). Culture of the bacterium on Columbia agar plus 5-7% defibrinated horse or sheep blood and selective Dent supplement under microaerophilic condition at 37degree Celsius for 3-5days.

OTHER

Histopathological examination endoscopic gastric biopsies:

Histological sections from the antrum and body regions will be stained with Giemsa stain. Giemsa stain working solution was prepared as follows: 40 ml Giemsa stock solution with 60 ml of distilled water. Giemsa stock solution will be prepared as follows: Giemsa powder 4 g, glycerol 250 ml and methanol 250 ml. Histological sections will be examined by a gastrointestinal pathologist to standardize the classification of gastritis. Histopathological classification will be recorded as following (acute gastritis, mild-moderate- severe chronic gastritis, Glandular atrophy or Intestinal metaplasia).

PROCEDURE

Upper endoscopy

it will be done patient before start empirical therapy and multiple antrum and/or corpus biopsies will be taken . Patient will be fasting at least 8 hours.Upper and findings will be recorded in the report as presence of gastroesophageal reflux disease, diffuse or localised gastric and/or duodenal redness, mucosal swelling, atrophy of mucosa, nodularity, intestinal metaplasia, erosions or ulcers.

DRUG

empirical H.pylori regimens

Start empirical antibiotics regimens patient triple therapy ((levofloxacin 400 mg once , amoxicillin 1000 mg twice for 2 weeks) and (Proton pump inhibitor twice for 1 month)). Follow up after 2 weeks after finishing regimen by Stool Ag in stool

DIAGNOSTIC_TEST

H.Pylori Ag in stool

Any symptomatic patient is above 18 years old with H pylori infection patients diagnosed by positive H pylori Ag in stool will be included. assessment of laboratory response, 2 weeks after finishing empirical therapy.

Sponsors & Collaborators

• Assiut University

  lead OTHER

Study Design

Allocation

NA

Purpose

TREATMENT

Masking

NONE

Model

SINGLE_GROUP

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2024-01-20

Primary Completion

2024-09-15

Completion

2025-01-20

Countries

• Egypt

Study Locations