PhD Scientific Days 2024

Pathological and Oncological Sciences I.

Detection of Helicobacter pylori and its clarithromycin resistance from formalin-fixed, paraffin-embedded gastric biopsy samples by quantitative real-time PCR.

Előadó neve

Ms. Biró, Adrienn, MSc

Neptun code

T0PA29

Előadó munkahelye

Department of Pathology, Forensic and Insurance Medicine, Semmelweis University, Budapest, Hungary

Előadó telefonszáma

+36304868448

Előadó e-mail címe

biro.adrienn@phd.semmelweis.hu

Az előadás címe

Detection of Helicobacter pylori and its clarithromycin resistance from formalin-fixed, paraffin-embedded gastric biopsy samples by quantitative real-time PCR.

Szerző(k) neve és munkahelye

Adrienn Biró¹, Anita Kurucz¹, Ákos Jakab¹, Ildikó Szirtes¹, Flóra Elamin¹, György Miklós Buzás², Veronika Papp³, Attila Szijártó³, András Kiss¹, Éva Kocsmár¹, Gábor Lotz¹

1: Department of Pathology, Forensic and Insurance Medicine, Semmelweis University, Budapest, Hungary
2: Department of Gastroenterology, Ferencváros Health Centre, Budapest, Hungary
3: Department of Surgery, Transplantation and Gastroenterology, Semmelweis University, Budapest, Hungary

Bemutatás módja

Szóbeli

Szekció

Pathological and Oncological Sciences I.

Language of the presentation

English

Preferred session

Pathological and Oncological Sciences

Összefoglaló szövege

Introduction: The diagnostic accuracy of detecting Helicobacter pylori (HP) and its clarithromycin susceptibility (Cla-susc) from gastric biopsies by immunohistochemistry (IHC) and fluorescence-in-situ-hybridization (FISH) compared to isolated DNA-based polymerase chain reaction (PCR) methods is still controversial and needs to be investigated.
Methods: Formalin-fixed paraffin-embedded (FFPE) gastric tissue samples from 209 patients were collected. Tissue sections were stained by Helicobacter-IHC and Cla-susc FISH. DNA was isolated for quantitative-PCR (qPCR), and a 122 bp sequence of the bacterial 23SrRNA gene was amplified using a custom designed primer pair.
Results: 108/209 specimens was HP-positive by IHC and FISH and 101 was HP-negative. Quantitative-PCR detected the bacterium from 102/108 IHC/FISH-HP-positive and 25/101 IHC/FISH-HP-negative cases. From the 42 samples Cla-susceptible by FISH, qPCR-melting point analysis identified 34/5/1 as Cla-susceptible/-heteroresistant/-homoresistant (and 2 HP-negative). From the 33 samples Cla-heteroresistant by FISH, 4/19/8 Cla-susceptible/-heteroresistant/-homoresistant (and 2 HP-negative) was found. From the 33 samples Cla-homoresistant by FISH, 0/2/29 Cla-susceptible/-heteroresistant/-homoresistant (and 2 HP-negative) was detected by qPCR.
Conclusion: QPCR performed adequately in detecting both HP and its clarithromycin-susceptibility status in IHC/FISH-positive cases. However, among IHC/FISH-negative cases, a substantial proportion (25%) was found to be HP-positive by qPCR. Owing to the discontinuous mucosal appearance of Helicobacter, it cannot be detected histopathologically in certain biopsy specimens, only by soluble DNA-based PCR, which is therefore recommended in IHC-negative cases.
Funding: The study was funded by the K_22 142604 grant of the National Research, Development and Innovation Office (Hungary), as well as the New National Excellence Program (ÚNKP-23-4-II-SE-24) and KDP-2023 Funding Scheme (2023-2.1.2-KDP-2023-00016) of the Ministry for Culture and Innovation from the source of the National Research, Development and Innovation Fund, Hungary.

University

Semmelweis University

Supervisor

Dr. Gábor Lotz

Publication of my abstract

I give consent to the publication of my abstract on the website of the congress.

Kind

Szabad

Status

elfogadva

Accepted presentation method

szóbeli

Előadás fájl jóváhagyás

nem rendelkezett róla

Előadó

8014

Start

11:00

End

11:10