Commercial real-time PCR kit results for the detection of Helicobacter pylori and clarithromycin resistance in stool...

Helicobacter pylori (H. pylori) is a bacterium that infects half of the world's population, and, unless treated, colonization usually persists throughout the lifespan. Noninvasive tests for the detection of H. pylori infections have indeed been valuable because of their ease of use and reduced discomfort. However, many noninvasive tests primarily focus on identifying the presence of bacteria rather than determining antimicrobial susceptibility. The purpose of this work was to use real-time PCR on stool samples to identify H. pylori infections and the point mutations that resulted in clarithromycin resistance.

A total of 63 patients attending to Gastroenterology Department of Hacettepe University Hospital were included between January 2021 and July 2022. Gastric biopsy culture, rapid urease test, histopathological analysis, stool antigen test, gastric biopsy and stool real-time PCR (RT-PCR) procedures were performed for the diagnosis of H. pylori. As the study's reference standard, a combination of two positive procedures were used.

Among the 63 patients included in the study, 42.9 % tested H. pylori positive, while 57.1 % tested H. pylori negative. When the reference standards were compared to stool RT-PCR; for H. pylori detection, sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy were determined 66.6 %, 100 %, 100 %, 80.0 %, 85.7 % respectively. In the detection of clarithromycin point mutations from stool samples with RT-PCR, the overall agreement was 65 % when compared to the results obtained from gastric biopsy RT-PCR.

In conclusion, the outcomes of this study indicate that utilizing RT-PCR from stool samples holds potential as a diagnostic tool for detecting H. pylori. This is particularly relevant in circumstances where invasive tests present challenges. However, further studies are recommended to validate and refine the method for clarithromycin resistance detection.