Granulomatous Upper Gastrointestinal Inflammation in Pediatric Ulcerative Colitis

"Brunner gland inflammation in Crohn's disease and Celiac disease: Overlapping inflammatory patterns suggest a possible link"

Similar to celiac disease, inflammatory bowel disease frequently manifests in the duodenum. Histopathologic studies focused on mucosal alterations with little attention to submucosal Brunner glands. Recently, several studies have demonstrated overlapping features between Crohn's disease and celiac disease suggesting a putative link. However, histopathologic studies evaluating this possible link are limited, and those that are focused on Brunner glands are lacking. The present study aims to explore whether Crohn's disease and celiac disease display shared or overlapping inflammatory changes in Brunner glands. We performed a retrospective review study over 17-years retrieving duodenal biopsy specimens containing Brunner gland lobules in patients with Crohn's disease, celiac disease, and ulcerative colitis. We found 10 out of 126 duodenal biopsies (8 %) in patients with Crohn's disease and 6 out of 134 (4.5 %) duodenal biopsies in patients with celiac disease sharing inflammatory patterns in duodenal Brunner gland lobules. Both diseases showed interstitial intralobular and interlobular mixed chronic inflammation with variable fibrosis. Focally enhanced active inflammation of Brunner gland lobules was more characteristic of Crohn's disease. Intralobular epithelioid granulomas and multinucleated giant cells were specific to Crohn's disease. Ulcerative colitis patients did not show similar features. The interstitial focally enhanced chronic inflammatory pattern was significantly (p < 0.05) associated with both diseases, while the other inflammatory patterns were not (p > 0.05). This overlapping inflammatory pattern in Brunner glands in patients with Crohn's disease and celiac disease is supportive of the previously reported link between the two diseases. Pathologists should pay more attention to Brunner glands when evaluating duodenal biopsies. Further studies are warranted to validate these observations and their relevance in the pathogenesis of autoinflammatory gastrointestinal diseases.

Mitochondrial Control in Inflammatory Gastrointestinal Diseases

Mitochondria play a central role in the pathophysiology of inflammatory bowel disease (IBD) and colorectal cancer (CRC). The maintenance of mitochondrial function is necessary for a stable immune system. Mitochondrial dysfunction in the gastrointestinal system leads to the excessive activation of multiple inflammatory signaling pathways, leading to IBD and increased severity of CRC. In this review, we focus on the mitochondria and inflammatory signaling pathways and its related gastrointestinal diseases.

SPP1 in infliximab resistant ulcerative colitis and associated colorectal cancer: an analysis of differentially expressed genes

OBJECTIVE

Infliximab, a tumour necrosis factor-α (TNFα) antagonist, has advanced the management of ulcerative colitis. Although efficacious, considerable percentage of patients are resistant to treatment. Accumulative inflammatory burden in long-term ulcerative colitis patients refractory to therapy increases the risk of developing colorectal cancer (CRC). Our study investigated anti-TNFα-naïve patients with active ulcerative colitis to identify gene biomarkers whose dysregulated expression correlated with resistance to infliximab (IFX) treatment and poor prognosis in CRC.

METHODS

Differentially expressed genes (DEGs) from two studies (GSE73661 and GSE14580) with colonic mucosal samples were retrieved. Noninflammatory bowel disease controls were compared with those with active ulcerative colitis that either responded or were resistant to IFX before treatment. DEGs from ulcerative colitis samples resistant to IFX were used to construct a protein-protein interaction network, and clustering gene modules were identified. Module DEGs that overlapped with ulcerative colitis samples responsive to IFX were analysed, based on topological closeness and radiality. Hub genes were obtained, and their correlation with CRC progression was evaluated. Their expression in CRC tissues and their tumour microenvironment immune status was estimated.

RESULTS

Three clusters composed of 582 DEGs from ulcerative colitis samples resistant to IFX were retrieved. Comparative analysis identified 305 overlapping DEGs with ulcerative colitis samples responsive to IFX. Topological analysis revealed a hub gene - SPP1 - whose overexpression in CRC tissues and patients correlated with increased infiltration of immune signatures and poor prognosis.

CONCLUSION

SPP1 may serve as potential gene biomarker and predictor of resistance to IFX therapy in ulcerative colitis and CRC development.

Mucosal lesions of the upper gastrointestinal tract in patients with ulcerative colitis: A review

Ulcerative colitis (UC) is a chronic, nonspecific, relapsing inflammatory bowel disease. The colorectum is considered the chief target organ of UC, whereas upper gastrointestinal (UGI) tract manifestations are infrequent. Recently, emerging evidence has suggested that UC presents complications in esophageal, stomachic, and duodenal mucosal injuries. However, UC-related UGI tract manifestations are varied and frequently silenced or concealed. Moreover, the endoscopic and microscopic characteristics of UGI tract complicated with UC are nonspecific. Therefore, UGI involvement may be ignored by many clinicians. In addition, no standard criteria have been established for patients with UC who should undergo fibrogastroduodenoscopy. Furthermore, specific treatment recommendations may be needed for patients with UC-associated UGI lesions. Herein, we review the esophageal, gastric, and duodenal mucosal lesions of the UC-associated UGI tract, as well as the potential pathogenesis and therapy.

Differentiation of Colonic Inflammatory Bowel Disease: Re-examination of Paediatric Inflammatory Bowel Disease Classes Algorithm With Resected Colon As the Criterion Standard

OBJECTIVES

Differentiation of Crohn disease (CD) from ulcerative colitis (UC) is challenging when inflammation is predominantly colonic. The paediatric inflammatory bowel disease (PIBD) classes algorithm was developed to bring consistency to labelling, but used physician-assigned diagnosis as the criterion standard. We aimed to reassess the PIBD classes using pathology of subsequently resected colon as the criterion standard.

METHOD

Single-centre study of patients diagnosed with colonic IBD between 2002 and 2017 and subsequently treated with colectomy. Baseline pretreatment data were reviewed and the PIBD classes algorithm was independently applied by 2 reviewers to assign a label of UC/IBD-unclassified (IBD-U)/colonic-CD. Concordance between the algorithm-based, precolectomy clinical, and pathologic examination of resected colon diagnosis were assessed. Changes in diagnosis during postcolectomy follow-up were recorded.

RESULTS

Sixty-two children underwent colectomy for medically refractory colonic IBD. Diagnosis based on pathologic review of resected colon CD:4;UC:56;IBDU:2. The clinical, PIBD classes algorithm, and colectomy diagnoses were concordant in 51 of 62 patients (81%, Fleiss kappa 0.48). Precolectomy clinical diagnosis was concordant with colectomy diagnosis in 58 of 62 patients (94%, weighted-kappa 0.65). The PIBD classes label was concordant with colectomy diagnosis in 51 of 62 patients (82%, weighted-kappa 0.38); resected colon pathology was typical of UC in 6 patients with PIBD classes label of IBD-U based on single class 2 feature and in 3 with PIBD classes label of CD based on single class 1 feature.

CONCLUSIONS

Concordance of PIBD classes algorithm diagnosis applied before colectomy with a diagnostic label based on pathologic examination of a subsequently resected colon is only fair. Caution is needed in stringent application of colonic CD and IBD-U labels based on presence of single feature.