Inflammatory bowel diseases (IBD), including colitis ulcerosa and Crohn’s disease, are chronic diseases of the gastrointestinal tract for which the cause has not been fully understood. However, it is known that the etiology is multifactorial. The multidirectional network of interactions of environmental, microbiological and genetic factors in predisposed persons lead to an excessive and insufficiently inhibited reaction of the immune system, leading to the development of chronic inflammation of the gastrointestinal walls, the consequence of which is the loss of the function that the intestine performs, inter alia, through the process of fibrosis. Detailed knowledge of the pathways leading to chronic inflammation makes it possible to pharmacologically modulate disorders and effectively treatthese diseases. In this review, we described the primary and adaptive immune system response in the gut and the known immune pathogenetic pathways leading to the development of IBD. We also described the process leading to intestinal tissue fibrosis, which is an irreversible consequence of untreated IBD.

Endoscopic ultrasonography (EUS) is a diagnostic endoscopy of the upper gastrointestinal tract, during which ultrasound of nearby organs is also performed. It is also possible to perform a fine needle aspiration biopsy. Currently, EUS is performed more frequently in adults. Despite some limitations, this diagnostic method is also more and more often performed in pediatric patients. Eosinophilic esophagitis (EoE) is a chronic inflammatory disease of the esophagus, which also occurs in children, and leads to irreversible fibrosis of the esophagus wall, if left untreated. Traditional methods of diagnosing and monitoring EoE treatment have significant limitations, and the use of EUS and total esophageal wall thickness (TWT) assessment may bring measurable benefits. Several studies have shown an increased thickening of TWT in EoE in children compared to pediatric patients with gastroesophageal reflux disease, and a decrease in TWT in adults who responded to EoE treatment. These results suggest that EUS and TWT measurement may become an important test in diagnostics, monitoring the effectiveness of therapy, assessing disease progression, and in individualizing the method and duration of EoE treatment also in children.

The coexistence of inflammatory bowel disease (IBD) with pancreatic pathology is rare in children. A retrospective analysis of data from 1538 children diagnosed with IBD in 2014–2021 was conducted to determine the frequency and causes of pancreatitis and asymptomatic hyperlipasemia (HL) or hyperamylasemia (HA) in this group of patients. Among the 176 children (11.4%) with pancreatic involvement (PI), acute pancreatitis (AP) was diagnosed in 77 children (43.8%), and HA or HL was observed in 88 children (50.0%). Only a few patients were diagnosed with autoimmune or chronic pancreatitis (6.2%). PI was observed at the time of the IBD diagnosis in 26.1% of the cases. A total of 54.5% of the patients had moderate to severe IBD, and 96% had colonic involvement at the time of diagnosis of PI. Idiopathic PI was the most common (57%), followed by drug-induced PI (37%) and azathioprine (AZA). In patients with AZA-induced AP, the successful introduction of 6-mercaptopurine (6-MP) to therapy was noted in 62.5% of the children. Our results suggest that routine monitoring of pancreatic enzymes in patients with IBD should be performed, especially after the initiation of the AZA treatment. The presence of transient HA/HL in IBD does not necessarily indicate pancreatic pathology.

Helicobacter pylori and Candida spp. are widespread microorganisms found in the human gastrointestinal tract, often coexisting in the same ecological niche. H. pylori, a Gram-negative bacterium, is a well-known pathogen responsible for gastritis, peptic ulcers, and gastric cancer. In contrast, Candida fungi, often detected in food, particularly Candida albicans, are generally considered commensal organisms, but can become opportunistic pathogens under certain conditions. Recent studies suggest a possible link between these microorganisms, highlighting a new survival strategy of H. pylori, that is, its ability to internalize in Candida vacuoles. This phenomenon, confirmed by various microscopic and molecular techniques, may provide H. pylori with protection against adverse environmental conditions, especially clinically important antibiotic therapy. The basic premise of this theory is the ability of H. pylori to penetrate vacuoles in fungal cells, which then become a reservoir of infection, allowing the infection to recur. Understanding the interaction between H. pylori and Candida may offer new insights into the pathogenesis of gastrointestinal diseases and may lead to the development of treatments targeting both organisms simultaneously. The purpose of this article is to review the literature, considering the first observations on this problem in the literature and the current state of knowledge, and to suggest a direction for further research.

Background/Objectives: Crohn’s disease is a chronic inflammatory condition with periods of exacerbation and remission that can involve any part of the gastrointestinal tract. The basic intestinal manifestation is frequently accompanied by extraintestinal involvement and may lead to complications such as perforations, fistulas and abscesses. Despite Crohn’s disease being the most common reason of intestinal perforation, the other causes should be considered as well. Internalization of a foreign body, although rare, may still occur, especially in the pediatric population. Methods: The following case report presents the medical history of an 11-year-old patient who developed an enterocutaneous fistula two years after the diagnosis of Crohn’s disease. Data analysis was carried out on the basis of patient medical records. Results: The fistula formed in the course of biological treatment during a period free of other symptoms indicating disease exacerbation. The imaging tests revealed the presence of a foreign body in the gastrointestinal tract, which could have been a potential cause of the observed inflammation that resulted in the development of the fistula. Conclusions: The presented case report as well as the literature indicate a correlation between the formation of intestinal fistulas and an active disease process. However, in the absence of symptoms of Crohn’s disease exacerbation, other causes should be considered.

Pentraxin 3 [PTX3] is an acute-phase protein playing an important role in the regulation of the humoral arm of immune response. As one of the molecules from the conservative family of pentraxins, PTX3 is a soluble mediator involved in the transduction of pro-inflammatory signals between immunocompetent cells. Additionally, recognizing damage-associated molecular patterns (DAMPs) during tissue injury mediates wound healing; therefore, its concentration potentially correlates with the severity of fibrosis. The aim of our study was to evaluate the value of the PTX3 measurement as a phenotypic marker of the stenotic form of Crohn’s disease. The research covered 63 patients, 35 with the narrowing type (B2) and 28 with the inflammatory type (B2) of CD. The mean concentrations of PTX3 in the study were as follows: 3.06 ng/mL (95% CI: 1.27–6.99) for the B1 phenotype, 4.89 ng/mL (95% CI: 2.98–13.65) for the B2 phenotype, and 3.04 ng/mL (95% CI: 1.01–4.97) for the control group. PTX3 concentrations reached the highest values in the B2 group and the lowest in the control group. The differences between the B1 and B2 groups were statistically significant at p < 0.001. The presented studies indicate the potential role of PTX3 in the monitoring of tissue remodeling and the development of fibrosis in CD.