Improving diagnosis and treatment of Helicobacter pylori
Eye on Innovation
Eye on Innovation features exciting advances taking place at Mayo Clinic Laboratories. This monthly series shines a spotlight on recently developed tests and highlights how Mayo Clinic translates ideas and discoveries into testing resources that improve diagnosis and care for patients across the globe.
Helicobacter pylori (H. pylori), a gastric pathogen, is one of the most common chronic bacterial infections in the world. As the main cause of peptic ulcer disease and a major risk factor for gastric cancer, H. pylori can lead to life-threatening medical conditions if left untreated. Timely, accurate diagnosis and successful treatment of H. pylori are critical for improving patients’ gastrointestinal health and preventing further harm.
Due to the increasing prevalence of antimicrobial resistance and the global emergence of multidrug-resistant strains of this pathogen, successful H. pylori eradication has become a challenge. Antibiotic resistance is not a small problem. For example, Mayo Clinic Laboratories found a 70% resistance rate to clarithromycin among 413 H. pylori isolates tested.
“Treatment of Helicobacter pylori has become more complex because of antimicrobial resistance,” says Robin Patel, M.D., the Elizabeth P. and Robert E. Allen Professor of Individualized Medicine and a professor of medicine and microbiology in the Division of Clinical Microbiology at Mayo Clinic in Rochester, Minnesota.
“Helicobacter pylori is typically treated with combinations of antibiotics along with a proton pump inhibitor. The initial course of therapy generally offers the greatest likelihood of treatment success. Therefore, careful attention must be paid to selection of the most appropriate first-line therapy for an individual patient.”
Robin Patel, M.D.
A crucial step in choosing the most appropriate therapy for H. pylori is accurately identifying its susceptibility to certain antibiotics. Until recently, that could only be accomplished via an invasive endoscopic procedure, and that procedure is not performed in many patients who are infected with this bacterium. Because of that, therapy has been a bit of a guessing game for many, based on resistance rates in other patients who undergo invasive endoscopic procedures that enable isolation of H. pylori in culture and its testing for antibiotic susceptibility.
Mayo Clinic Laboratories now offers a noninvasive option that uses a fecal specimen for the molecular detection of H. pylori, with results delivered within 24 hours of the laboratory receiving a sample.
The test is called Helicobacter pylori with Clarithromycin Resistance Prediction, Molecular Detection, PCR, Feces. Not only does the assay identify H. pylori infection, it also predicts clarithromycin resistance or susceptibility by the three most common H. pylori 23S ribosomal RNA gene single nucleotide variations (A2143G, A2142G, and A2142C) that lead to clarithromycin resistance. In addition, the test can be used to assess the effectiveness of treatment by confirming that H. pylori has been eradicated once treatment is complete. This is the only test of its kind that is clinically available in the microbiology industry.
In a recently published evaluation using this assay, clarithromycin resistance was found in 28% of Mayo Clinic patients who had not received treatment for H. pylori infection. Importantly, clarithromycin-based therapy success was lower when resistance was predicted by PCR than when no resistance was predicted.
Using results of this assay, clinicians are able to determine the best therapy for eradicating H. pylori in each patient on an individual basis without the guesswork — an approach that helps patients get the right treatment, right away.
For more information about H. pylori and the research Mayo Clinic has conducted regarding its diagnosis and resistance to antibiotics, view the Mayo Clinic Laboratories Education Hot Topic: What’s new in Helicobacter pylori testing, presented by Dr. Patel.