Helicobacter pylori infections, as one of the most prevalent among humans, are generally acquired during childhood, and are one of the main causes of chronic gastritis and peptic ulcer disease. A bacterial culture from a gastric biopsy is the gold standard and is the only method that has 100% specificity. However, its sensitivity varies, depending on experience of the laboratory staff, applied culture media, specimen transport conditions, biopsy site, and quality of the sample. The same factors compromise all invasive methods and a culture-based H. pylori infection diagnostic, as well as a recent intake of antibiotics, bismuth-containing compounds, and proton pump inhibitors. Molecular methods have been used for clinical microbiology investigation since the beginning of the 21st century. However, their usefulness for H. pylori infections diagnosis remains unclear, especially in pediatric patients. The aim of the study was to assess the incidence of H. pylori infections in a group of 104 pediatric patients and to compare the results of the PCR test with the corresponding histopathological investigation effects. Among the biopsy samples collected from 104 children, 44 (42.3%) were positive in PCR, while 43 (41.3%) and 39 (37.5%) presented histologically-confirmed signs of inflammation and H. pylori colonization, respectively. Moreover, the mean grades of the parameters of the histopathological examination were higher in the group of PCR-positive samples. The compatibility of both research methods was confirmed, emphasizing the usefulness of molecular methods for detecting H. pylori infections in pediatric patients. Considering that the PCR-based method gives reliable results and is less time-consuming and costly, it is worth discussing this method as a new standard in the diagnosis of H. pylori infections, at least among pediatric patients, for which culture-based diagnostics is not sufficient or histopathological examination is negative, while inflammation signs are observed macroscopically.

Ulcerative colitis (UC) results from a complex interplay between the environment, gut microbiota, host genetics, and immunity. Runt-related transcription factor 3 (RUNX3) regulates Th1/Th2 balance and, thus, the synthesis of cytokines and inflammation. We aimed to analyze the dependence of RUNX3 promoter 2 (P2) methylation level on: age, sex, body mass index (BMI), C-reactive protein (CRP), serum albumin, disease duration, Pediatric Ulcerative Colitis Activity Index (PUCAI), the Paris classification, and exposure to medications. This multicenter, cross-sectional study recruited hospitalized children with UC. Methylation of RUNX3 P2 was measured with methylation-sensitive restriction enzymes in the whole blood DNA. Sixty-four children were enrolled, with a mean age of 14.5 ± 2.8 years. Half of them were female (51.6%), and the average BMI Z-score was −0.44 ± 1.14. The mean methylation of RUNX3 P2 was 54.1 ± 13.3%. The methylation level of RUNX3 P2 did not correlate with age, sex, nutritional status, CRP, albumin, PUCAI, or the extent of colitis (Paris E1–E4). RUNX3 P2 methylation did not differ between patients recruited within two and a half months of diagnosis and children who had UC for at least a year. Current or past exposure to biologics, immunosuppressants, or steroids was not associated with RUNX3 P2 methylation. Methylation of RUNX3 promoter 2 in whole blood DNA does not seem to be associated with the characteristics of UC in children.

Deleted in malignant brain tumours 1 protein (DMBT1) and surfactant protein D (SFTPD) are antimicrobial peptides previously linked to inflammatory bowel disease (IBD) susceptibility. This study attempts to link the most potential IBD-associated polymorphisms in DMBT1 and SFTPD with the disease severity in children. A total of 406 IBD patients (Crohn’s disease (CD) n = 214 and ulcerative colitis (UC) n = 192) were genotyped using hydrolysis probe assay. Clinical expression was described by disease activity scales, albumin and C-reactive protein levels, localisation and behaviour (Paris classification), systemic steroid, immunosuppressive, biological, and surgical treatment, number of exacerbation-caused hospitalisations, relapses and nutritional status. IBD patients with the risk genotype (AA) in DMBT1 rs2981804 had more frequent biological treatment (AA: vs. AG/GG; p = 0.012), concomitant diseases (AA vs. AG vs. GG; p = 0.015) and cutaneous manifestations (AA vs. AG/GG, p = 0.008). In UC, rs2981804 genotypes might be linked with albumin concentrations at diagnosis (AA vs. AG vs. GG; p = 0.009). In CD, DMBT1 rs2981745 was significantly associated with the number of severe relapses per year of disease (p = 0.020) and time-to-immunosuppression (p = 0.045). SFTPD was seemingly found to be associated with age at first immunosuppression in IBD (CC vs. CT vs. TT; p = 0.048). In conclusion, selected polymorphisms of DMBT1 and SFTPD might be associated with some disease severity measures in children with IBD. However, the magnitude of associations and their clinical relevance might be minor.

Background: Helicobacter pylori is a Gram-negative bacterium responsible for various gastrointestinal diseases, including peptic ulcers and gastric cancer. Despite available antibiotic therapies, increasing resistance to clarithromycin—a key antibiotic in eradication regimens—poses a significant challenge. This resistance is primarily linked to point mutations in the 23S rRNA gene, particularly A2143G, A2142G, and A2142C, which hinder clarithromycin binding, reducing its bacteriostatic efficacy. This study aimed to assess the prevalence and variability of clarithromycin resistance mutations in pediatric patients from Bydgoszcz, Poland. Methods: A total of 45 gastric biopsy samples from pediatric patients were analyzed using the Bosphore® Helicobacter pylori Genotyping Kit v1 to detect clarithromycin resistance-associated mutations. Results: Among the 45 tested samples, 30 were classified as wild-type, while 12 contained resistance-associated mutations. The most frequently detected mutation was A2143G (58.3%), followed by A2142G (33.3%). One sample exhibited both A2142G and A2143G mutations, and another contained a mixture of wild-type and mutant strains. The A2142C mutation was not detected in any sample. Conclusions: Our findings confirm the predominance of A2143G among clarithromycin-resistant H. pylori strains, consistent with global trends. The detection of both mutant and wild-type strains in a single patient highlights potential co-infections or subpopulations with varying resistance profiles. Continuous surveillance and improved diagnostic tools are crucial for optimizing treatment strategies. Tailored eradication protocols based on resistance profiling are necessary to enhance treatment efficacy and mitigate the spread of resistant strains. Further research is needed to understand the clinical implications of mixed infections and double mutations in H. pylori resistance development.

In 40 unique pediatric biopsy samples, this study aimed to compare the obtained results of Helicobacter pylori DNA detection using next-generation sequencing (NGS), a real-time PCR-based IVD-certified kit and an established high resolution melting real-time PCR-based method for H. pylori-specific ureA gene. From the same group, the H. pylori DNA was identified in 16 (40.0%) samples in both real-time PCR-based methods, with quantification cycle (Cq) values ranging from 17.51 to 32.21 for the IVD kit. NGS was able to detect H. pylori DNA in 14 (35.0%) samples, with read counts between 7768 and 42,924. While all three methods showed similar detection rates, both PCR variants were slightly more sensitive, identifying H. pylori in two additional samples not detected by NGS. The study highlights the strengths and limitations of each method. NGS, though promising due to its high sensitivity and ability to detect low bacterial load, is still limited by its cost and complexity. Despite these challenges, NGS could complement PCR in diagnosing difficult or ambiguous cases, enabling the detection of multiple pathogens simultaneously. Especially when other infectious etiologies are suspected, NGS could be considered, though PCR variants remain a more attractive and cost-effective option for routine H. pylori detection.