Helicobacter pylori Infection and Antimicrobial Resistance Surveillance over 25 Years in Children in Gipuzkoa, Northern Spain

The diagnosis and treatment of <i>Helicobacter pylori</i> infection in children represent a major public health problem worldwide, and although prevalence in developed countries has declined, concern about antibiotic resistance continues to grow. This retrospective study aimed to analyze <i>H. pylori</i> infections in children under 15 years of age in Gipuzkoa (Basque Country, Spain) over a 25-year period and to describe patterns of primary and secondary antimicrobial resistance. All diagnostic tests received at a tertiary referral hospital between 2000 and 2024 were reviewed: urea breath test, gastric biopsy culture, string test, and stool antigen detection. Antimicrobial susceptibility testing was performed using the E-test gradient diffusion method. Out of 2855 children investigated, 26.9 were infected with <i>H. pylori</i>. Eradication control was performed in 62.5% (<i>n</i> = 480) of cases. Antimicrobial susceptibility testing was achieved in 96.5% out of the 400 isolates studied. All isolates were sensitive to amoxicillin and tetracyclines. Primary resistance to clarithromycin, metronidazole, and levofloxacin was 28.9%, 19.4%, and 8.9%, respectively, and secondary resistance was 38.7%, 29.7%, and 5.9%, respectively. <i>H.pylori</i> infection remains a challenge in pediatric patients, and the high resistance observed to clarithromycin and metronidazole makes it necessary to monitor the susceptibility of <i>H.pylori</i> and confirms the need for targeted treatment.