Neto, Manuel B. Braga

ABSTRACT Presented is a 76-year-old man with metastatic melanoma that was successfully treated with pembrolizumab, an immune checkpoint inhibitor (ICI). He underwent 20 months of ICI treatment without dose limiting side effects. Nearly 18 months after ICI discontinuation, the patient developed intermittent epigastric pain and diarrhea. Owing to mild symptoms, he was not immediately evaluated. Three years after ICI cessation, he was diagnosed with stricturing, jejunal Crohn's disease. He was treated with vedolizumab and displayed clinical and radiographic response to treatment. This case serves as an example of potential gastrointestinal-related, long-term autoimmune implications of ICI therapy, even in patients without acute side effects.

Abstract Introduction The aim of this case–control study was to determine if exposure to tumor necrosis factor alpha inhibitors (TNFIs) or immunomodulators (thiopurines or methotrexate) was associated with development of primary gastrointestinal lymphoma (PGIL) in patients with chronic inflammatory conditions. Methods Patients with PGIL and controls evaluated at a tertiary care center over 20 years were matched 1:3 using a medical record informatics search engine based on their chronic inflammatory condition (Crohn’s disease [CD], ulcerative colitis [UC], rheumatoid arthritis, ankylosing spondylitis, and psoriatic arthritis) and duration of follow-up. Patients who started on TNFI within 3 months of PGIL diagnosis were excluded. We extracted demographics, medical history, and medications used. Univariate models using conditional logistic regression were used due to the small number of matched pairs. Results Twenty PGIL cases matched with 60 controls were followed for a mean 9.9 ± 6.9 and 9.7 ± 8.6 years, respectively. Mean age at time of PGIL diagnosis was 47.5 ± 22.0 (standard deviation) years and the majority (75%) were males. The most common inflammatory diagnosis was inflammatory bowel disease (80% of cases; 45% with UC and 35% with CD). Development of PGIL was not associated with TNFI (odds ratio [OR] = 2.6; 95% confidence interval [CI] 0.69–11.01; P = .18), but with use of TNFI in combination with thiopurines (OR = 8.93; 95% CI 1.43–80.25; P = .014). Risk of PGIL increased with every additional TNFI (2.277 (1.002–5.713); P = .0494). All cases exposed to multiple TNFI were also exposed to thiopurines. Use of thiopurines (alone or in combination) was the greatest risk factor (OR = 6.32; 95% CI 1.55–37.05; P = 0.006) to develop PGIL. Conclusions TNFI therapy was not associated with increased risk for PGIL unless used in combination with thiopurines and with every switch to a different TNFI.

Abstract Background The development of Crohn’s disease [CD] involves immune cell signalling pathways regulated by epigenetic modifications. Aberrant DNA methylation has been identified in peripheral blood and bulk intestinal tissue from CD patients. However, the DNA methylome of disease-associated intestinal CD4+ lymphocytes has not been evaluated. Materials and Methods Genome-wide DNA methylation sequencing was performed from terminal ileum CD4+ cells from 21 CD patients and 12 age- and sex-matched controls. Data were analysed for differentially methylated CpGs [DMCs] and methylated regions [DMRs]. Integration was performed with RNA-sequencing data to evaluate the functional impact of DNA methylation changes on gene expression. DMRs were overlapped with regions of differentially open chromatin [by ATAC-seq] and CCCTC-binding factor [CTCF] binding sites [by ChIP-seq] between peripherally derived Th17 and Treg cells. Results CD4+ cells in CD patients had significantly increased DNA methylation compared to those from the controls. A total of 119 051 DMCs and 8113 DMRs were detected. While hypermethylated genes were mostly related to cell metabolism and homeostasis, hypomethylated genes were significantly enriched within the Th17 signalling pathway. The differentially enriched ATAC regions in Th17 cells [compared to Tregs] were hypomethylated in CD patients, suggesting heightened Th17 activity. There was significant overlap between hypomethylated DNA regions and CTCF-associated binding sites. Conclusions The methylome of CD patients shows an overall dominant hypermethylation yet hypomethylation is more concentrated in proinflammatory pathways, including Th17 differentiation. Hypomethylation of Th17-related genes associated with areas of open chromatin and CTCF binding sites constitutes a hallmark of CD-associated intestinal CD4+ cells.

Abstract IBD affects roughly 1.6 million US adults, with its prevalence increasing since the late 1990s. Characterized by unchecked intestinal inflammation, multiple proinflammatory cytokines including IL6 have been implicated as critical factors in this pathology. It has been established that EZH2 is a gene involved in the production of specific histone methyltransferase enzymes, as well as in the differentiation of Treg cells. The association between the Treg master transcription factor, Foxp3 and EZH2 results in the suppressive function of Tregs, with our previous work revealing impairment of this interaction under the influence of IL6 signaling in an inflamed intestinal setting. We investigated this further in a murine preventative T cell transfer model of colitis that involved injecting donor Treg cells that lacked IL6Ra, into immunocompromised mice. Histological scoring of the mice receiving the IL6Rko Tregs revealed a resolved inflammatory milieu and flow cytometric analysis of cells isolated from the spleens and MLNs showed increased Foxp3+ expression when compared to mice that received WT Tregs. Foxp3IL6Rako mice were subjected to a DSS model of colitis to further characterize the absence of the IL6R on Treg function in the intestinal milieu. Exacerbated signs of colitis were observed through histology and colon shortening of the conditional knockout mice when compared to their WT counterparts. We postulate that Tregs could be acting as a donor of sILR to promote intestinal integrity and healing. Further experiments will be conducted to define a role for the IL6R in the development of Foxp3+ cells, along with outlining the instrumental process of sIL6R donation in the intestinal milieu. Supported by Mayo Clinic Graduate School for Biomedical Sciences

Abstract Background Upadacitinib is a selective Janus kinase inhibitor approved for the management of ulcerative colitis and is under evaluation for the management of Crohn’s disease [CD] in Phase 3 clinical trials. Aims Our goal was to describe our real-world experience with upadacitinib in CD. Methods This is a two-centre retrospective cohort study of adult patients with moderate to severe CD on upadacitinib. The primary outcome was clinical response and remission as determined by stool frequency and abdominal pain scores. Secondary endpoints included endoscopic response and remission as determined by change in Simple Endoscopic Score for CD. Outcomes were assessed at 3 months after starting upadacitinib and at the patient’s most recent follow-up. We further evaluated adverse events and dose-related response. Results A total of 45 CD patients received upadacitinib and were included in the safety analysis. Thirty-six patients received upadacitinib for CD, whereas nine received it for inflammatory arthritis [n = 8] or pyoderma [n = 1]. Thirty-three patients received upadacitinib for 3 months or longer and were included in the efficacy analysis. At the 3-month follow-up, 21 patients achieved clinical response [63.6%] and nine achieved clinical remission [27.2%]. At time of last follow-up, 23 patients had clinical response [69.7%], ten achieved clinical remission [30.3%] and four [28.6%] achieved endoscopic remission. Adverse events occurred in 12 patients [26.7%]. Two patients had a serious adverse event [4.5%] without associated mortality. Conclusion In this real-world cohort of highly refractory CD patients, upadacitinib was effective in inducing remission and had an acceptable safety profile.

ABSTRACT The purpose of this case series is to review the endoscopic detection of anal intraepithelial neoplasia and anal squamous cell carcinoma including the role of rectal retroflexion and narrow-band imaging. Four cases of anal intraepithelial neoplasia were incidentally discovered in women aged 55–71 years. Anal lesions identified included sessile polyps, nodular mucosa, and circumferential polyps. A fifth patient, who presented with abdominal pain, was found to have a 3 cm anal squamous cell carcinoma on diagnostic colonoscopy, despite a negative colonoscopy 21 months earlier. In the absence of contraindications, retroflexion should be performed on all patients. Suspicious anal mucosa warrants biopsy.

Abstract Background Microscopic colitis (MC) is suspected to result from increased immune activity in gut mucosa. Immune checkpoint inhibitors (ICIs) treat cancer by activating the immune system, and further investigation is needed regarding their role in the development of MC. Methods A retrospective case series investigated cases of endoscopically and histologically confirmed MC developing after administration of ICIs. Clinical notes and medication administration records were reviewed for demographics, symptom duration, and treatment response. Results Nineteen cases of de novo MC were identified, with 95% of cases requiring steroid treatment, 53% presenting with hospitalization, and colitis-related mortality in 1 individual. Symptom onset occurred a median of 160 days after initiation of ICI therapy and 53 days after their most recent dose of therapy. Patients had a median of 125 days of symptoms, and ICI therapy was held in 70% of individuals due for treatment. Conclusions MC can develop after ICI administration, and presents with severe symptoms, often requiring hospitalization and steroid treatment. In certain individuals this can require a prolonged treatment course of steroid therapy or immunomodulators. Individuals developing diarrhea after ICI therapy warrant thorough workup including endoscopy and rapid treatment initiation given the disease severity observed in this series.

LINKED CONTENT This article is linked to Meserve et al paper. To view this article, visit https://doi.org/10.1111/apt.16217