Upper gastrointestinal bleeding (UGIB) is a significant concern in children, contributing to 6–20% of cases in pediatric intensive care units. This study evaluates the roles of Helicobacter pylori (H. pylori) infection and non-steroidal anti-inflammatory drug (NSAID) usage in the etiology of UGIB in children, with a particular focus on trends observed during the COVID-19 pandemic. We conducted a retrospective analysis of 103 pediatric patients who underwent esophagogastroduodenoscopy (EGD) for UGIB between January 2015 and December 2023. Of these, 88 patients were included in the final analysis, where the source of bleeding was successfully identified. Hematemesis was the most common presentation, and the source of bleeding was identified in 85.43% of cases. The prevalence of H. pylori infection remained stable across the pre-pandemic (39.7%) and post-pandemic (36.7%) periods. However, NSAID usage increased nearly threefold during the pandemic, with 36.7% of post-pandemic UGIB cases associated with NSAID use, compared to 12.1% pre-pandemic. These findings underscore the significant roles of H. pylori and NSAID use in pediatric UGIB, with a notable increase in NSAID-related cases during the pandemic.

Background: Pediatric gastroesophageal reflux disease (GERD) presents with heterogeneous phenotypes across ages, and diagnostic challenges persist. Multichannel intraluminal impedance and pH (MII-pH) monitoring is the current gold standard, while mean nocturnal baseline impedance (MNBI) has emerged as a marker of mucosal integrity in adults. Pediatric normative data are still lacking. We aim to characterize age-related reflux patterns and assess the association between MNBI and pathological acid exposure in children undergoing MII-pH monitoring. Methods: We retrospectively analyzed 226 children evaluated with 24 h MII-pH monitoring between 2017 and 2025. Clinical and laboratory data were reviewed. Children were stratified by age ( 10% in infants and >7% in older children. MNBI was measured at distal channels (Z5, Z6) during nocturnal recumbency. Correlations between MNBI and RI were assessed. Diagnostic performance of MNBI for pathological acid exposure was evaluated using ROC analysis. Results: Infants had more total reflux episodes, particularly weakly acidic and liquid, whereas older children exhibited more gas reflux. MNBI correlated inversely with RI (Z6 r = −0.337; Z5 r = −0.281; both p < 0.0001). In infants, MNBI poorly discriminated pathological acid exposure. In older children, MNBI showed better performance, with optimal cut-offs of ~2525 Ω (Z6) and 3079 Ω (Z5) yielding specificities > 85%. Conclusions: MNBI is a reproducible, age-sensitive marker of reflux burden in children, best suited for older children where it complements RI in diagnosing acid-mediated GERD. Larger prospective studies are needed to establish pediatric reference values.