LAUSR

Helicobacter pylori (H. pylori), a microaerophilic gramnegative proteobacterium, is the most common human pathogen colonizing the gastric mucosa of over half the world's population.1,2 Although 70% of infected people are symptomless, H. pylori is recognized as a strong causative factor in many gastrointestinal (GI) diseases such as peptic ulcer, atrophic gastritis, gastric cancer, and mucosaassociated lymphoid tissue (MALT) lymphoma.3 The transmission of H. pylori is usually through persontoperson contact or from environmental sources via oraloral, fecaloral, and gastrooral routes.4 Therefore, its infection rate is linked to familial socioeconomic status, overcrowding, poor hygiene, and environmental contamination in food and water supply.5 While maintaining a spiral rodshaped form in a favorable environment, H. pylori may transform into coccoid shape, a viable but nonculturable (VBNC) form with low metabolic activity, to survive under stressful conditions including oxygen deprivation, antibiotic exposure, and epithelial attachment.6 Treatment of the infection is usually a combination of acid inhibitory agents (eg, Proton Pump Inhibitors PPI) and antibiotics (ie, amoxicillin, clarithromycin, metronidazole, and tetracycline), the choice of which depends on antibiotic sensitivity.7 Efficient diagnosis is required for successful clinical management to relieve symptoms and to eradicate bacteria. Clinicians have developed numerous H. pylori detection methods, which are divided into two groups based on whether samples are collected by invasive endoscopy.8 Serology, urea breath test (UBT), and stool antigen test (SAT) are the noninvasive tests carried out on stool, breath, saliva, or serum samples.9 The invasive tests including endoscopy, histology, culture, and rapid urease test (RUT) are carried out on gastric biopsies.10 All these conventional tests are based on the presence of different components such as enzymes (UBT, RUT), antigens (SAT), bacteria (culture), and antibodies (serology, histology).11 Several reviews have discussed their advantages and disadvantages in accuracy, sensitivity, specificity, simplicity, and cost.1215 To improve conventional methods, especially sensitivity, some molecular techniques based on DNA/RNA have been recently used in both invasive and noninvasive H. pylori diagnosis.16 These new methods include polymerase chain reaction (PCR),17 realtime PCR,18 droplet digital PCR (ddPCR),19 fluorescent in situ hybridization (FISH),20 and nextgeneration sequencing (NGS) including 16S rRNA amplicon sequencing,16 transcriptomics,21 and metagenomics.22 In this issue, Gantuta et al.23 discussed the advantages of 16S rRNA sequencing in H. pylori diagnosis, which brings to attention the need to review molecular detection tests, especially their shortcomings. This editorial summarizes our current understanding of molecular methods, focusing on applications, limitations, and improvements.