Eradication success and change in antibiotic resistance after the incorporation of PCR in the approach to Helicobacter pylori infection

Introduction: incorporation of PCR in the approach to Helicobacter pylori (HP) infection could improve the diagnosis and eradication rates of this infection, due to its greater diagnostic sensitivity and ability to detect resistance to macrolides. The objective of this study was to compare eradication success according to 3 different diagnostic strategies depending on the microbiological test used. Antibiotic resistance of H.P. was analyzed in the last decade. Patients and methods: retrospective analysis of the eradication rate according to the microbiological approach used (2013-2016: culture; 2017-2019: culture + PCR; 2020-2023: PCR). The cost-effectiveness ratio (CEAR) was calculated based on the costs of direct diagnostic tests. Antibiotic resistance of HP was analyzed between 2013 and 2023. Results: 288 patients (98 detected by culture, 94 by culture + PCR, 96 by PCR), 228 treated. Eradication rates: 67.5%, 86.2% and 95.8% respectively, significant difference between periods 1-2 and 1-3 (p < 0.001), but not between 2-3 (p = 0.087). Strategy 3 was the most cost-effective (CEAR 26.74). Macrolide resistance increased progressively (1-16.3%; 2-53.2%; 3-58%). In absence of PCR, the rates would have been 16.3%, 30.8% and 34.3%, respectively. The rest of antibiotic resistances remained stable. Conclusions: the incorporation of PCR resulted in a significant increase in eradication rates. The combination of culture + PCR did not improve these results, only PCR was the most cost-effective strategy. Macrolide resistance exceeded 50% in periods where PCR was available.