Clinical Evaluation of a Real-Time PCR Assay for Simultaneous Detection of Helicobacter pylori and Genotypic Markers of Clarithromycin Resistance Directly from Stool
| Autor: | Erin T Polo, Rebecca M. Marrero Rolon, Robin Patel, Scott A. Cunningham, Jayawant N. Mandrekar |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
0301 basic medicine
Microbiology (medical) medicine.medical_specialty 030106 microbiology Gastroenterology 03 medical and health sciences symbols.namesake 0302 clinical medicine Clarithromycin Internal medicine Genotype Clarithromycin resistance Medicine Sanger sequencing biology business.industry Helicobacter pylori bacterial infections and mycoses biology.organism_classification Regimen Real-time polymerase chain reaction symbols 030211 gastroenterology & hepatology business Clinical evaluation medicine.drug |
| Zdroj: | Journal of Clinical Microbiology. 59 |
| ISSN: | 1098-660X 0095-1137 |
| Popis: | Helicobacter pylori infection is mainly diagnosed noninvasively, with susceptibility testing traditionally requiring endoscopy. Treatment is empirical, with clarithromycin-based triple therapy recommended where resistance rates are below 15%. Rising rates of clarithromycin resistance, resulting in high clarithromycin-based therapy failure rates, are seen worldwide, but U.S. data are limited. We developed a real-time PCR assay for simultaneous detection of H. pylori and genotypic markers of clarithromycin resistance directly from stool specimens. The assay was validated by testing 524 stool samples using an H. pylori stool antigen test as the reference method for detection accuracy and Sanger sequencing to confirm genotypic susceptibility results. A separate set of 223 antigen-positive stool samples was tested and retrospective medical record review conducted to define clinical utility. PCR resulted in 88.6% and 92.8% sensitivity in the validation and clinical study sets, respectively. Sequencing confirmed correct detection of clarithromycin resistance-associated mutations in all positive validation samples. The PCR-predicted clarithromycin resistance rate was 39% in the clinical data set overall and 31% in treatment-naive patients; the clarithromycin-based triple therapy eradication rate in treatment-naive patients was 62%. The clarithromycin-based triple therapy success was lower when resistance was predicted by PCR (41%) than when no resistance was predicted (70%; P = 0.03). PCR results were positive in 98% of antigen-positive stools from patients tested for eradication. The described PCR assay can accurately and noninvasively diagnose H. pylori, provide genotypic susceptibility, and test for eradication. Our findings support the need for susceptibility-guided therapy in our region if a clarithromycin-based regimen is considered. |
| Databáze: | OpenAIRE |
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