Efficacy of Loop-Mediated Isothermal Amplification for H. pylori Detection as Point-of-Care Testing by Noninvasive Sampling

Abstract

For targeted eradication of Helicobacter pylori (H. pylori) to reduce gastric cancer burden, a convenient approach is definitely needed. The purpose of this study was to evaluate the LAMP assay for H. pylori detection using samples collected by noninvasive and self-sampling methods. The available LAMP assay for H. pylori detection was appraised and verified using reference and clinically isolated H. pylori strains. In addition, a clinical study was conducted to assess the LAMP assay on 51 patients, from whom saliva, oral brushing samples, feces, corpus, and antrum specimens were available. Clarithromycin resistance was also analysed through detection of A2143G mutation using the LAMP-RFLP method. The validation and verification analysis demonstrated that the LAMP assay had an acceptable result in terms of specificity, sensitivity, reproducibility, and accuracy for clinical settings. The LAMP assay showed a detection limit for H. pylori down to 0.25 fg/µL of genomic DNA. An acceptable consensus was observed using saliva samples (sensitivity 58.1%, specificity 84.2%, PPV 85.7%, NPV 55.2%, accuracy 68%) in comparison to biopsy sampling as the gold standard. The performance testing of different combinations of noninvasive sampling methods demonstrated that a combination of saliva and oral brushing could achieve a sensitivity of 74.2% and a specificity of 57.9%. A2143G mutation detection by LAMP-RFLP showed perfect consensus with Sanger sequencing results. It appears that the LAMP assay in combination with noninvasive and self-sampling as a point-of-care testing (POCT) approach has potential usefulness to detect H. pylori infection in clinic settings and screening programs.

The validity evaluation of different 16srRNA gene primers for helicobacter detection urgently requesting to design new specific primers

“…The clinical precision testing by PCR was applied on gastric biopsies from dyspeptic patients introduced to the endoscope unit in the mentioned hospitals, revealing that all PCR results are consistent with the invasive methods applied (RUT and Histopathology). The positive PCR by sequencing confirmed the presence of Helicobacter DNA in the samples 48 – 50 The ConsH detected 40.7% positive samples, from the positive Helicobacter spp. PCR, the nested PCR detected 61.3% H. pylori and 39.7% Non-Helicobacter pylori Helicobacters (NHPH).…”

Design of novel specific primers for helicobacter detection with diagnostic utility evaluation of different 16srRNA genus-specific primers: A comparative study

“…The clinical precision testing by PCR was applied on gastric biopsies from dyspeptic patients introduced to the endoscope unit in the mentioned hospitals, revealing that all PCR results are consistent with the invasive methods applied (RUT and Histopathology). The positive PCR by sequencing confirmed the presence of Helicobacter DNA in the samples [51–53]. The ConsH detected 40.7% positive samples, from the positive Helicobacter spp.…”

Review of foodborne helicobacteriosis

“…Polymerase chain reaction (PCR) is an emerging option that can be categorized as both invasive and non-invasive tests. The PCR approach is beneficial for detecting H. pylori from gastric biopsies without the need for cultures (Sohrabi et al, 2021).…”