Asian Organization for Crohn's and Colitis and Asia Pacific Association of Gastroenterology practice recommendations for medical management and monitoring of inflammatory bowel disease in Asia

Management of ulcerative colitis in Taiwan: consensus guideline of the Taiwan Society of Inflammatory Bowel Disease updated in 2023

Ulcerative colitis (UC) is a chronic inflammation of the gastrointestinal tract and is characterized by alternating periods of inflammation and remission. Although UC incidence is lower in Taiwan than in Western countries, its impact remains considerable, demanding updated guidelines for addressing local healthcare challenges and patient needs. The revised guidelines employ international standards and recent research, emphasizing practical implementation within the Taiwanese healthcare system. Since the inception of the guidelines in 2017, the Taiwan Society of Inflammatory Bowel Disease has acknowledged the need for ongoing revisions to incorporate emerging therapeutic options and evolving disease management practices. This updated guideline aims to align UC management with local contexts, ensuring comprehensive and context-specific recommendations, thereby raising the standard of care for UC patients in Taiwan. By adapting and optimizing international protocols for local relevance, these efforts seek to enhance health outcomes for patients with UC.

Management of Crohn's disease in Taiwan: consensus guideline of the Taiwan Society of Inflammatory Bowel Disease updated in 2023

Crohn's disease (CD) is a chronic, fluctuating inflammatory condition that primarily affects the gastrointestinal tract. Although the incidence of CD in Taiwan is lower than that in Western countries, the severity of CD presentation appears to be similar between Asia and the West. This observation indicates the urgency for devising revised guidelines tailored to the unique reimbursement system, and patient requirements in Taiwan. The core objectives of these updated guidelines include the updated treatment choices and the integration of the treat-to-target strategy into CD management, promoting the achievement of deep remission to mitigate complications and enhance the overall quality of life. Given the diversity in disease prevalence, severity, insurance policies, and access to medical treatments in Taiwan, a customized approach is imperative for formulating these guidelines. Such tailored strategies ensure that international standards are not only adapted but also optimized to local contexts. Since the inception of its initial guidelines in 2017, the Taiwan Society of Inflammatory Bowel Disease (TSIBD) has acknowledged the importance of continuous revisions for incorporating new therapeutic options and evolving disease management practices. The latest update leverages international standards and recent research findings focused on practical implementation within the Taiwanese healthcare system.

High prevalence of vitamin D deficiency in Taiwanese patients with inflammatory bowel disease

Vitamin D deficiency is common in patients with inflammatory bowel disease (IBD). In this study, we aimed to evaluate the prevalence and risk factors of vitamin D deficiency in a Taiwanese IBD cohort. Vitamin D levels were checked in adult patients with IBD who were treated at Changhua Christian Hospital, a medical center in central Taiwan, from January 2017 to December 2023. The risk factors for vitamin D deficiency were evaluated. 106 adult IBD patients were included, including 20 patients with Crohn's disease and 86 with ulcerative colitis. The median age at diagnosis was 39.2 years. The mean vitamin D level was 22.2 ± 8 ng/mL. Forty-five patients (42.5%) had vitamin D deficiency (vitamin D level < 20 ng/mL). Comparing patients with normal vitamin D levels and those with vitamin D deficiency after multivariate adjustment, female sex and early age at diagnosis were identified as statistically significant risk factors. We found a prevalence of 42.5% of vitamin D deficiency in the Taiwanese IBD population. Understanding this issue is essential for teaching patients and doctors about vitamin D deficiency screening and improving patient outcomes.

Deep learning model to differentiate Crohn's disease from intestinal tuberculosis using histopathological whole slide images from intestinal specimens

Crohn's disease (CD) and intestinal tuberculosis (ITB) share similar histopathological characteristics, and differential diagnosis can be a dilemma for pathologists. This study aimed to apply deep learning (DL) to analyze whole slide images (WSI) of surgical resection specimens to distinguish CD from ITB. Overall, 1973 WSI from 85 cases from 3 centers were obtained. The DL model was established in internal training and validated in external test cohort, evaluated by area under receiver operator characteristic curve (AUC). Diagnostic results of pathologists were compared with those of the DL model using DeLong's test. DL model had case level AUC of 0.886, 0.893 and slide level AUC of 0.954, 0.827 in training and test cohorts. Attention maps highlighted discriminative areas and top 10 features were extracted from CD and ITB. DL model's diagnostic efficiency (AUC = 0.886) was better than junior pathologists (*1 AUC = 0.701, P = 0.088; *2 AUC = 0.861, P = 0.788) and inferior to senior GI pathologists (*3 AUC = 0.910, P = 0.800; *4 AUC = 0.946, P = 0.507) in training cohort. In the test cohort, model (AUC = 0.893) outperformed senior non-GI pathologists (*5 AUC = 0.782, P = 0.327; *6 AUC = 0.821, P = 0.516). We developed a DL model for the classification of CD and ITB, improving pathological diagnosis accuracy effectively.

Colorectal Neoplasia in the Setting of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is associated with an increased risk of colorectal cancer (colorectal adenocarcinoma [CRC]) compared with the general population. IBD-related CRC is related to poorer outcomes than non-IBD-related CRC, and it accounts for 10% to 15% of death in patients with IBD. As such, screening guidelines have been made specific to this population recommending shorter intervals of endoscopic screening to detect dysplasia and CRC relative to the general population. Advances in endoscopic technology allow for improved visualization of dysplasia, which has led to widespread adoption of dye-spray chromoendoscopy with targeted biopsy.

Differentiation of Crohn's disease, ulcerative colitis, and intestinal tuberculosis by dual-layer spectral detector CT enterography

AIM

To investigate the value of radiological features and energy spectrum quantitative parameters in the differential diagnosis of Crohn's disease (CD), ulcerative colitis (UC), and intestinal tuberculosis (ITB) by dual-layer spectral detector computed tomography (CT) enterography (CTE).

MATERIALS AND METHODS

Clinical and CTE data were collected from 182 patients with CD, 29 with UC, and 51 with ITB. CT images were obtained at the enteric phases and portal phases. The quantitative energy spectrum parameters were iodine density (ID), normalised ID (NID), virtual non-contrast (VNC) value, and effective atomic number (Z-eff). The area under curve (AUC) of the receiver operating characteristic curve (ROC) was calculated.

RESULTS

The vascular comb sign (p=0.009) and enlarged lymph nodes (p=0.001) were more common in patients with CD than UC or ITB. In the differentiation of moderate-severe active CD from UC, enteric phase NID (AUC, 0.938; p<0.001) and portal phase Z-eff (AUC, 0.925; p<0.001) had the highest accuracy, which were compared separately. In the differentiation of moderate-severe active CD from ITB, enteric phase NID (AUC, 0.906; p<0.001) and portal phase Z-eff (AUC, 0.947; p<0.001) had the highest accuracy; however, the AUC value was highest when the four parameters are combined (AUC, 0.989; p<0.001; AUC, 0.986; p<0.001; AUC, 0.936; p<0.001; and AUC, 0.986; p<0.001).

CONCLUSION

The present study shows that the combined strategies of four parameters have higher sensitivity and specificity in differentiating CD, UC, and ITB, and may play a key role in guiding treatment.

Thiopurines Have Sustained Long-term Effectiveness in Patients with Inflammatory Bowel Disease, Which is Independent of Disease Duration at Initiation: A Propensity Score Matched Analysis

BACKGROUND AND AIMS

Thiopurines are viable option for the treatment of inflammatory bowel disease [IBD] in resource-limited countries. However, data on the effect of disease duration at thiopurines initiation on long-term effectiveness are limited.

METHOD

We performed a propensity matched analysis of a retrospective cohort of patients with ulcerative colitis [UC] and Crohn's disease [CD]. Patients initiated on thiopurines early in the disease course [≤2 years] were compared with those started late [>2 years]. Effectiveness was defined as no requirement for hospitalisation, anti-tumour necrosis factor [TNF] agents, or surgery, and minimum steroid requirement [≤1 steroid course in 2 years] during follow-up.

RESULTS

A total of 988 [UC: 720, CD: 268] patients were included (male: 665 [60.8%], median age: 40 [32-51] years, median follow-up: 40 [19-81] months). Overall effectiveness at 5 and 10 years was 79% and 72% in UC, and 69% and 63% in CD, respectively. After propensity score matching, there was no difference in 5- and 10-year effectiveness between early and late thiopurine initiation groups either for UC [81% and 80% vs 82% and 74%; p = 0.92] or CD [76% and 66% vs 72% and 51%, p = 0.32]. Male sex for UC (negative: hazard ratio [HR]: 0.67, 95% confidence interval [CI): 0.45-0.97; p = 0.03), and ileal involvement [positive: HR: 3.03, 95% CI: 1.32-6.71; p = 0.008], steroid-dependent disease [positive: HR: 2.70, 95% CI: 1.26-5.68; p = 0.01] and adverse events [negative: HR: 0.47, 95% CI:0.27-0.80; p = 0.005] for CD were predictors of thiopurine effectiveness.

CONCLUSION

Thiopurines have sustained long-term effectiveness in both UC and CD. However, early thiopurine initiation had no better effect on long-term disease outcome compared with late initiation.

International clinical practice guideline on the use of traditional Chinese medicine for ulcerative colitis by Board of Specialty Committee of Digestive System Disease of World Federation of Chinese Medicine Societies (2023)

Ulcerative colitis (UC), a chronic and nonspecific inflammatory disease of the intestine, has become a prevalent global health concern. This guideline aims to equip clinicians and caregivers with effective strategies for the treatment and management of adult UC patients using traditional Chinese medicine (TCM). The guideline systematically evaluated contemporary evidence through the Grading of Recommendations Assessment, Development, and Evaluation framework. Additionally, it incorporated insights from ancient Chinese medical sources, employing the evidence grading method found in traditional TCM literature. The development process involved collaboration with multidisciplinary experts and included input from patients with UC. The guideline, based on a comprehensive review of available evidence, present 40 recommendations. They offer a condensed overview of TCM's role in understanding the pathogenesis, diagnosis, and treatment of UC, along with an assessment of the efficacy of various TCM-based treatments. TCM exhibits promising outcomes in the treatment of UC. However, to establish its efficacy conclusively, further high-quality clinical studies on TCM for UC are essential.

Porcine-derived antimicrobial peptide PR39 alleviates DSS-induced colitis via the NF-κB/MAPK pathway

PR39 is an antimicrobial peptide (AMP) with a variety of biological functions, including antimicrobial, wound healing, leukocyte chemotaxis, angiogenesis, and immunomodulation; however, its therapeutic efficacy in colitis (IBD) has rarely been reported. For this reason, the present study aimed to investigate the therapeutic effect of PR39 on IBD and its underlying mechanisms. In this experiment, a mouse model of ulcerative colitis (UC) was induced with 3 % dextran sulfate (DSS) and administered by rectal injection of PR39. The results of the study showed that 5 mg/kg of PR39 was able to ameliorate the clinical manifestations of DSS-induced UC mice by improving the clinical symptoms, colonic tissue damage, up-regulating the expression of tight junction proteins, and alleviating the systemic inflammation in mice in various ways. The mechanism of action may involve inhibition of the phosphorylation level of proteins related to the NF-κB/MAPK signaling pathway and modulation of the relative abundance of potentially pathogenic (Bacteroides, Pseudoflavonifractor, Barnesiella, and Oscillibacter) and potentially beneficial bacteria (Candidatus_Saccharibacteria, Desulfovibrio, Saccharibacteria) in the intestinal flora. The results enriched the biological functions of PR-39 and also suggested that PR-39 may be able to be used as a novel drug for the treatment of IBD.

The effectiveness of continuity of care in patients with inflammatory bowel disease: a systematic review

AIM

To investigate the effectiveness of continuity of care in patients with inflammatory bowel disease.

BACKGROUND

The prevalence of inflammatory bowel disease(IBD) is increasing by years, especially in China. Moreover, IBD is prolonged and difficult to heal, which seriously impairs the quality of life of patients. Some studies have identified that continuity of care could contribute to the improvement of the quality of life, but the results remains inconclusive in patients with IBD.

METHODS

PRISMA guidelines was the outline of this study. Review Manager Software (version 5.3) was used to carry out the data analysis. Outcome assessments included quality of life (QoL), remission rates, number of outpatient clinic visits, and medication adherence.

RESULTS

Ultimately, 12 studies involving 2415 patients were brought into this meta-analysis. The results indicated there was no significant difference for continuity of care to improve the QoL in intervention group (SMD = 0.02, 95% CI: -0.08, 0.12). Besides, the remission rates of disease had no difference with those patients in the two groups (OR = 1.07, 95% CI: 0.72, 1.60). However, continued care could contribute to the number of outpatient clinic visits (MD = -0.84, 95% CI: -1.19, -0.49) and patients' adherence to medication significantly (OR = 2.40, 95% CI: 1.16, 4.95).

CONCLUSIONS

IBD patients could benefited from continuity of care with reducing their number of clinic visits and improving medication adherence. Nonetheless, there was no evidence of continuity of care contribute to QoL and remission of disease for these patients.

Diagnostic performance of sonographic activity scores for adult terminal ileal Crohn's disease compared to magnetic resonance and histological reference standards: experience from the METRIC trial

OBJECTIVES

The simple ultrasound activity score for Crohn's disease (SUS-CD) and bowel ultrasound score (BUSS) are promising intestinal ultrasound (IUS) indices of CD, but studied mainly in small settings with few sonographers. We compared SUS-CD and BUSS against histological and magnetic resonance enterography (MRE) reference standards in a post hoc analysis of a prospective multicentre, multireader trial.

METHODS

Participants recruited to the METRIC trial (ISRCTN03982913) were studied, including those with available terminal ileal (TI) biopsies. Sensitivity and specificity of SUS-CD and BUSS for TI CD activity were calculated with 95% confidence intervals (CI), from the prospective observations of the original METRIC trial sonographers against the histological activity index (HAI) and the simplified magnetic resonance index of activity (sMARIA).

RESULTS

We included 284 patients (median 31.5 years, IQR 23-46) from 8 centres, who underwent IUS and MRE. Of these, 111 patients had available terminal ileal biopsies with HAI scoring. Against histology, sensitivity and specificity for active disease were 79% (95% CI 69-86%) and 50% (31-69%) for SUS-CD, and 66% (56-75%) and 68% (47-84%) for BUSS, respectively. Compared to sMARIA, the sensitivity and specificity for active CD were 81% (74-86%) and 75% (66-83%) for SUS-CD, and 68% (61-74%) and 85% (76-91%) for BUSS, respectively. The sensitivity of SUS-CD was significantly greater than that of BUSS against HAI and sMARIA (p < 0.001), but its specificity was significantly lower than of BUSS against the MRE reference standard (p = 0.003).

CONCLUSIONS

Particularly when compared to MRE activity scoring, SUS-CD and BUSS are promising tools in a real-world clinical setting.

CLINICAL RELEVANCE STATEMENT

When tested using data from a multicentre, multireader diagnostic accuracy trial, the simple ultrasound activity score for Crohn's disease (SUS-CD) and bowel ultrasound score (BUSS) were clinically viable intestinal ultrasound indices that were reasonably sensitive and specific for terminal ileal Crohn's disease, especially when compared to a magnetic resonance reference standard.

KEY POINTS

The simple ultrasound activity score for Crohn's disease and bowel ultrasound score are promising intestinal ultrasound indices of Crohn's disease but to date studied mainly in small settings with few sonographers. Compared to histology and the magnetic resonance reference standard in a multicentre, multireader setting, the sensitivity of simple ultrasound activity score for Crohn's disease is significantly greater than that of bowel ultrasound score. The specificity of simple ultrasound activity score for Crohn's disease was significantly lower than that of bowel ultrasound score compared to the magnetic resonance enterography reference standard. The specificity of both indices was numerically higher when the magnetic resonance enterography reference standard was adopted.

Efficacy and safety of risankizumab for Crohn's disease in patients from Asian countries: a post hoc subanalysis of the global phase 3 ADVANCE, MOTIVATE, and FORTIFY studies

BACKGROUND AND AIM

The anti-interleukin-23 antibody risankizumab is being investigated as a treatment for moderate-to-severe Crohn's disease. This post hoc subanalysis evaluates the efficacy and safety of risankizumab therapy in Asian patients.

METHODS

ADVANCE (NCT03105128) and MOTIVATE (NCT03104413) were randomized, double-blind, placebo-controlled, phase 3 induction studies. Patients with intolerance/inadequate response to biologic (MOTIVATE) and/or conventional therapy (ADVANCE) were randomized to receive intravenous risankizumab (600 or 1200 mg) or placebo at weeks 0, 4, and 8. Clinical responders to risankizumab could enter the phase 3, randomized, double-blind, placebo-controlled maintenance withdrawal study (FORTIFY; NCT03105102). Patients were rerandomized to receive subcutaneous risankizumab (180 or 360 mg) or placebo (withdrawal) every 8 weeks for 52 weeks.

RESULTS

Among 198 Asian patients in the induction studies, clinical remission and endoscopic response at week 12 were achieved by 61.4% and 40.0%, 59.5% and 35.8%, and 27.3% and 9.1% of patients in the risankizumab 600 mg, risankizumab 1200 mg, and placebo groups, respectively. Among 67 patients who entered the maintenance study, clinical remission and endoscopic response at week 52 were achieved by 57.1% and 52.4%, 75.0% and 40.0%, and 53.8% and 34.6% of patients in the risankizumab 180 mg, risankizumab 360 mg, and placebo (withdrawal) groups, respectively. Fistula closure was observed with risankizumab treatment in 28.6% (induction) and 57.1% (maintenance) of patients. Efficacy trends and safety profile were similar to those in non-Asian patients.

CONCLUSION

Consistent with non-Asian and global population results, risankizumab was effective and well tolerated in Asian patients with Crohn's disease.

Visceral Fat Indices: Do They Help Differentiate Crohn's Disease and Intestinal Tuberculosis in Children?

BACKGROUND AND AIMS

Crohn's disease [CD] and intestinal tuberculosis [ITB] are often difficult to differentiate. Mesenteric fat hypertrophy is a feature of CD. We evaluated the utility of fat indices (visceral fat [VF] and subcutaneous fat [SF]) in differentiating CD and ITB in children.

METHODS

Symptomatic children diagnosed to have CD or ITB based on recommended criteria were enrolled. Clinical, anthropometric, and laboratory details were noted. Abdominal fat was measured on computed tomography in supine position at the level of L4 vertebrae. VF and SF area was measured separately by a radiologist, blinded to the diagnosis. The sum of VF and SF was taken as total fat [TF]. VF/SF and VF/TF ratios were calculated.

RESULTS

Thirty-four (age 14 years [10.8-17.0], 14 boys) children were recruited: 12 had CD [seven boys, age 13.0 years] and 22 had ITB [seven boys, age 14.5 years]. VF area was higher in CD compared to ITB (18.34 cm2 [15.62-40.01] vs 6.48 cm2 [2.65-21.96]; p = 0.012). The SF and TF area was similar in ITB and CD. The ratios of VF/SF (0.82 [0.57-1.5] vs 0.33 [0.16-0.48]; p = 0.004) and VF/TF (0.45 [0.36-0.60] vs 0.25 [0.13-0.32]; p = 0.004) were significantly higher in CD. On comparing CD and ITB in boys and girls separately, the difference was significant for boys but not for girls. A VF/SF ratio of 0.609 predicted CD with a good sensitivity [75%] and specificity [86.4%] [area under the curve 0.795, 95% confidence interval 0.636-0.955; p = 0.005].

CONCLUSION

The VF/SF ratio is a simple, non-invasive, objective parameter to differentiate CD and ITB in children, particularly boys. Larger studies are needed to validate this in girls.

Inflammatory bowel disease and Clostridium difficile infection: clinical presentation, diagnosis, and management

As a frequent complication of inflammatory bowel disease (IBD), Clostridium difficile infection (CDI) was confirmed to not only aggravate the symptoms of IBD but also result in unexpected outcomes, including death. With the increasing prevalence rate of IBD and the updating of CDI diagnosis, the incidence of CDI in IBD patients is also seen rising. Although a detection method consisting of glutamate dehydrogenase immunoassay or nucleic acid amplification test and then toxin A/B enzyme immunoassay was recommended and widely adopted, the diagnosis of CDI in IBD is still a challenge because of the overlap between the symptoms of CDI in IBD and CDI itself. Vancomycin and fidaxomicin are the first-line therapy for CDI in IBD; however, the treatment has different effects due to the complexity of IBD patients' conditions and the choice of different treatment schemes. Although the use of fecal microbial transplantation is now in the ascendant for IBD management, the prospects are still uncertain and the prevention and treatment of the recurrence of CDI in IBD remain a clinical challenge. In this paper, the epidemiology, pathophysiology, clinical manifestation, prevention, and therapy of CDI in IBD were summarized and presented.

IBD barriers across the continents - East Asia

Inflammatory bowel diseases (IBDs) are chronic illnesses with significant morbidities and impact on patients' quality of life. There has been a rapid increase in the incidence of IBD in East Asia in recent decades. However, there is a huge unmet need in the diagnosis and management of IBD in this region. With the increasing awareness of IBD in East Asia and a persistently high rate of tuberculosis in this region, this poses a significant challenge in the diagnosis and management of IBD. In this review, we will explore the barriers to the diagnosis and management of IBD in the East Asia, hoping to provide an insight on how to improve the healthcare system in the management of this complex disease.

Cytomegalovirus Pneumonia in Inflammatory Bowel Disease: Literature Review and Clinical Recommendations

Aim

The objective was to elucidate the correlation between CMVP and immunosuppressive therapy in IBD patients, we hope this review could expand on the significance of CMV as an opportunistic pathogen and the potential impact on morbidity and mortality in IBD patients.

Methods

Records and clinical trajectories linked to CMVP in IBD patients were extracted from the PubMed database, irrespective of language barriers. The reference lists incorporated in these studies were manually inspected. Conclusions were generated using straightforward descriptive analysis.

Results

In total, 18 IBD patients, including Crohn's disease (CD, 67%) and Ulcerative Colitis (UC, 33%), affected by CMVP were identified from 17 published articles. A minority of these patients (17%) exhibited active disease, whereas the majority (83%) presented with quiescent disease. Fever (100%) and dyspnea (44%) emerged as the most prevalent clinical symptoms. All the patients had undergone immunosuppressive therapy. A significant proportion, up to 89%, had received thiopurine treatment prior to the CMVP diagnosis. Interestingly, none of the patients were subjected to biological therapy. Half of the patients manifested with Hemophagocytic Lymphohistiocytosis (HLH). Almost all patients (94%) were administered antiviral treatment and a substantial 83% experienced full recovery. Immunosuppressive agents were either tapered or discontinued altogether. A subset of patients, 17%, suffered fatal outcomes.

Conclusion

Our findings underscore the need for heightened suspicion of CMVP in IBD patients who exhibit symptoms such as fever and dyspnea. During the COVID-19 pandemic, CMVP should be considered a potential differential diagnosis. It was observed that CMVP primarily transpires during CD remission. Azathioprine emerged as the predominant immunosuppressant linked to CMV reactivation. The prompt application of effective antiviral therapy can substantially enhance patient outcomes. CMV vaccine might serve as a viable prevention strategy.

Temporal trends in surgery for Crohn's disease: a ten-year single-center retrospective study

PURPOSE

Crohn's disease (CD) is a chronic inflammatory bowel disease that requires surgery in many cases. The aim of this article is to present the experience of a referral center regarding surgical interventions for CD, while also exploring the transformations that have occurred over 10 years.

METHODS

The data of patients underwent abdominal surgery for CD between 2013 and 2022 were collected prospectively. Data were compared between two periods (2013-2017 and 2018-2022). Temporal trends were assessed with the Mann-Kendall trend test.

RESULTS

A total of 1059 individuals underwent 1176 surgical procedures, of which 67.1% were male. The median age of patients at the time of surgery was 36.0 years, and an overall increasing trend was observed in surgical volume (z = 3.04; p = 0.002). The proportion of patients treated with biologics increased from the first period (2013-2017) to the second (2018-2022), rising from 19.2% to 33.5% (p < 0.001). In the second stage, the proportion of patients who underwent surgery for abscesses or fistulas increased (47.8% vs. 40.0%, p = 0.028), while the percentage of emergency surgeries declined (3.0% vs. 7.1%, p = 0.001). Furthermore, there was a rise in the proportion of laparoscopic surgeries (76.5% vs. 63.7%, p < 0.001), coupled with a decrease in stoma rates (15.4% vs. 30.5%, p < 0.001) and postoperative complications (23.0% vs. 30.5%, p = 0.007).

CONCLUSION

The frequency of biologics use in CD surgery have increased over time, and the proportion of penetrating patients has grown. Minimally invasive surgical methods have become the norm, and surgical outcomes have markedly enhanced, evidenced by a substantial reduction in both stoma rates and complication rates.

Inflammatory Bowel Disease and Colorectal Cancer: Epidemiology, Etiology, Surveillance, and Management

Patients with inflammatory bowel diseases (IBDs), such as ulcerative colitis and Crohn's disease, have an increased risk of developing colorectal cancer (CRC). Although advancements in endoscopic imaging techniques, integrated surveillance programs, and improved medical therapies have contributed to a decreased incidence of CRC in patients with IBD, the rate of CRC remains higher in patients with IBD than in individuals without chronic colitis. Patients with IBD-related CRCs exhibit a poorer prognosis than those with sporadic CRCs, owing to their aggressive histological characteristics and lower curative resection rate. In this review, we present an updated overview of the epidemiology, etiology, risk factors, surveillance strategies, treatment recommendations, and prognosis of IBD-related CRCs.

Update and latest advances in mechanisms and management of colitis-associated colorectal cancer

Colitis-associated colorectal cancer (CAC) is defined as a specific cluster of colorectal cancers that develop as a result of prolonged colitis in patients with inflammatory bowel disease (IBD). Patients with IBD, including ulcerative colitis and Crohn's disease, are known to have an increased risk of developing CAC. Although the incidence of CAC has significantly decreased over the past few decades, individuals with CAC have increased mortality compared to individuals with sporadic colorectal cancer, and the incidence of CAC increases with duration. Chronic inflammation is generally recognized as a major contributor to the pathogenesis of CAC. CAC has been shown to progress from colitis to dysplasia and finally to carcinoma. Accumulating evidence suggests that multiple immune-mediated pathways, DNA damage pathways, and pathogens are involved in the pathogenesis of CAC. Over the past decade, there has been an increasing effort to develop clinical approaches that could help improve outcomes for CAC patients. Colonoscopic surveillance plays an important role in reducing the risk of advanced and interval cancers. It is generally recommended that CAC patients undergo endoscopic removal or colectomy. This review summarizes the current understanding of CAC, particularly its epidemiology, mechanisms, and management. It focuses on the mechanisms that contribute to the development of CAC, covering advances in genomics, immunology, and the microbiome; presents evidence for management strategies, including endoscopy and colectomy; and discusses new strategies to interfere with the process and development of CAC. These scientific findings will pave the way for the management of CAC in the near future.

Investigation of the Association Between ITPA Gene 94C>A Sequence Variant and Kidney Transplant Rejection in Iranian Kidney Transplant Recipients

OBJECTIVES

Thiopurine prodrugs are commonly used in kidney transplant recipients. Inosine triphosphate pyrophosphatase is an enzyme encoded by the ITPA gene. Alteration of ITPA gene is one of the pharmacogenetic sequence variants possibly involved in thiopurine metabolism. The ITPA 94C>A sequence variant (C-to-A substitution at nucleotide 94) is associated with an increased risk of adverse drug reactions in patients treated with the thiopurine drug. The aim of the present study was to investigate the effect of the ITPA 94C>A gene sequence variant in kidney transplant recipients.

MATERIALS AND METHODS

The genotyping of the ITPA rs1127354 variant was performed by the polymerase chain reaction restriction fragment length polymorphism method in 140 kidney transplant recipients and in 100 control participants. Data were analyzed with SPSS statistical software.

RESULTS

The results revealed a significant difference between control and nonrejection groups regarding the rs1127354 genotype and allele frequency. No significant difference was found between the rejection and nonrejection groups regarding the rs1127354 genotype and allele frequency. Also, a significant association was observed between the ageofthe control group and age of the rejection group. No significant differences between sex and underlying disease in patients with or without rejection were observed.

CONCLUSIONS

We observed no significant differences between rejection and nonrejection transplant. Further studies are recommended, in a larger population and with different ethnicities.

Differentiating gastrointestinal tuberculosis and Crohn's disease- a comprehensive review

Gastrointestinal Tuberculosis (GITB) and Crohn's disease (CD) are both chronic granulomatous diseases with a predilection to involve primarily the terminal ileum. GITB is often considered a disease of the developing world, while CD and inflammatory bowel disease are considered a disease of the developed world. But in recent times, the epidemiology of both diseases has changed. Differentiating GITB from CD is of immense clinical importance as the management of both diseases differs. While GITB needs anti-tubercular therapy (ATT), CD needs immunosuppressive therapy. Misdiagnosis or a delay in diagnosis can lead to catastrophic consequences. Most of the clinical features, endoscopic findings, and imaging features are not pathognomonic for either of these two conditions. The definitive diagnosis of GITB can be clinched only in a fraction of cases with microbiological positivity (acid-fast bacilli, mycobacterial culture, or PCR-based tests). In most cases, the diagnosis is often based on consistent clinical, endoscopic, imaging, and histological findings. Similarly, no single finding can conclusively diagnose CD. Multiparametric-based predictive models incorporating clinical, endoscopy findings, histology, radiology, and serology have been used to differentiate GITB from CD with varied results. However, it is limited by the lack of validation studies for most such models. Many patients, especially in TB endemic regions, are initiated on a trial of ATT to see for an objective response to therapy. Early mucosal response assessed at two months is an objective marker of response to ATT. Prolonged ATT in CD is recognized to have a fibrotic effect. Therefore, early discrimination may be vital in preventing the delay in the diagnosis of CD and avoiding a complicated course.

Diagnosis of inflammatory bowel disease-Asian perspectives: the results of a multinational web-based survey in the 8th Asian Organization for Crohn's and Colitis meeting

BACKGROUND/AIMS

Inflammatory bowel disease (IBD) is no longer a rare disease in Asia, thus it needs to prepare recommendations relevant to Asian patients. This study aimed to identify disparities in the process of the diagnosis of IBD in Asian countries/regions.

METHODS

In line with the 2020 Asian Organization for Crohn's and Colitis annual meeting, a multinational web-based survey about Asian physicians' perspectives on IBD was conducted.

RESULTS

A total of 384 Asian physicians (99 in China, 93 in Japan, 110 in Korea, and 82 in other Asian countries/regions) treating IBD patients from 24 countries/regions responded to the survey. Most respondents were gastroenterologists working in an academic teaching hospital. About half of them had more than 10 years of clinical experience in caring for patients with IBD. The European Crohn's Colitis Organisation guideline was used most commonly for the diagnosis of IBD except for Japanese physicians who preferred their own national guideline. The Mayo score and Crohn's Disease Activity Index were the most commonly used activity scoring systems for ulcerative colitis and Crohn's disease, respectively. Endoscopy, not surprisingly, was the main investigation in assessing the extent and activity of IBD. On the other hand, there were disparities across countries/regions with regard to the favored modalities of small bowel and perianal evaluation of Crohn's disease, as well as the use of serologic markers.

CONCLUSIONS

Results of the present survey revealed practical behaviors of Asian physicians in the diagnosis of IBD. Investigating the reasons for different diagnostic approaches among countries/regions might help us develop Asian guidelines further.

Content of Telephone Consultations of Patients With Inflammatory Bowel Disease: A Single-Center Descriptive Study

This study aimed to analyze the specific contents of telephone consultations of patients with inflammatory bowel disease. A medical record survey was conducted at a clinic in Japan for 1 year. Telephone consultation sheets recorded by nurses for calls with the patients or their relatives were reviewed. Content analysis was used to summarize the telephone consultation content. Consultations were categorized into 8 categories. Coding was conducted by 2 independent researchers. Concordance rates were evaluated using kappa coefficients. We analyzed 476 sheets. A total of 229 participants consulted the clinic at least once. The mean number of consultations per person was 2.1. Of these patients, 96 (40.9%) had ulcerative colitis. The kappa coefficient was 0.89. The most frequent consultation was "Consultation on worsening health: Inflammatory bowel disease is likely to have worsened" (42.0%). The second most frequent response was "Consultation or progress report on a worsening health condition: The disease is unlikely to have worsened" (19.8%). For consultations related to worsening the disease, it would be useful to assess symptoms over the phone using a disease activity index to ascertain the degree of worsening and to develop a screening tool for determining whether patients can continue remote support or require face-to-face consultation.

Plasma lipidomic profiling of thiopurine-induced leukopenia after NUDT15 genotype-guided dosing in Chinese IBD patients

Introduction

Thiopurines, azathiopurine (AZA) and mercaptopurine (6-MP) have been regularly used in the treatment of inflammatory bowel disease (IBD). Despite optimized dosage adjustment based on the NUDT15 genotypes, some patients still discontinue or change treatment regimens due to thiopurine-induced leukopenia.

Methods

We proposed a prospective observational study of lipidomics to reveal the lipids perturbations associated with thiopurine-induced leukopenia. One hundred and twenty-seven IBD participants treated with thiopurine were enrolled, twenty-seven of which have developed thiopurine-induced leucopenia. Plasma lipid profiles were measured using Ultra-High-Performance Liquid Chromatography-Tandem Q-Exactive. Lipidomic alterations were validated with an independent validation cohort (leukopenia n = 26, non-leukopenia n = 74).

Results

Using univariate and multivariate analysis, there were 16 lipid species from four lipid classes, triglyceride (n = 11), sphingomyelin (n = 1), phosphatidylcholine (n = 1) and lactosylceramide (n = 3) identified. Based on machine learning feature reduction and variable screening strategies, the random forest algorithm established by six lipids showed an excellent performance to distinguish the leukopenia group from the normal group, with a model accuracy of 95.28% (discovery cohort), 79.00% (validation cohort) and an area under the receiver operating characteristic (ROC) curve (ROC-AUC) of 0.9989 (discovery cohort), 0.8098 (validation cohort).

Discussion

Our novel findings suggested that lipidomic provided unique insights into formulating individualized medication strategies for thiopurines in IBD patients.

The overall quality of evidence of recommendations surrounding nutrition and diet in inflammatory bowel disease

BACKGROUND AND AIM

Recently, there has been an increased focus on the role nutrition and diet play in maintaining health in inflammatory bowel disease (IBD). We aimed to assess the overall quality, strength, and transparency of conflicts among guidelines on nutrition/diet in IBD.

METHODS

A systematic search was performed on multiple databases from inception until January 1, 2021, to identify guidelines pertaining to nutrition or diet in IBD. All guidelines were reviewed for disclosure of conflicts of interest (COI) and funding, recommendation quality and strength, external document review, patient representation, and plans for update-as per Institute of Medicine (IOM) standards. In addition, recommendations and their quality were compared between guidelines/societies.​ RESULTS: Seventeen distinct societies and a total of 228 recommendations were included. Not all guidelines provided recommendations on key aspects of diet-such as the role of supplements or the appropriate micro/macro nutrition in IBD. Fifty-nine percent of guidelines reported on COI, 24% underwent external review, and 41% included patient representation. 18.4%, 25.9%, and 55.7% of recommendations were based on high-, moderate-, and low-quality evidence, respectively. 10.5%, 24.6%, and 64.9% of recommendations were strong, weak/conditional, and did not provide a strength, respectively. The proportion of high-quality evidence (p = 0.12) and strong recommendations (p = 0.83) did not significantly differ across societies.

CONCLUSIONS

Many guidelines do not provide recommendations on key aspects of diet/nutrition in IBD. As over 50% of recommendations are based on low-quality evidence, further studies on nutrition/diet in IBD are warranted to improve the overall quality of evidence.

Health Maintenance and Preventative Care in Inflammatory Bowel Disease: A Systematic Review of the Overall Quality of Societal Recommendations

BACKGROUND AIMS

Preventative care plays an important role in maintaining health in patients with inflammatory bowel disease (IBD). We aimed to assess the overall quality, strength, and transparency of conflicts among guidelines on preventative care in IBD.

METHODS

A systematic literature search was performed in multiple databases to identify all guidelines pertaining to preventative care in IBD in April 2021. All guidelines were reviewed for the transparency of conflicts of interest and funding, recommendation quality and strength, external guideline review, patient voice inclusion, and plan for update-as per Institute of Medicine standards. In addition, recommendations and their quality were compared between societies.

RESULTS

Fifteen distinct societies and a total of 89 recommendations were included. Not all guidelines provided recommendations on the key aspects of preventative care in IBD-such as vaccinations, cancer prevention, stress reduction, and diet/exercise. Sixty-seven percent of guidelines reported on conflicts of interest, 20% underwent external review, and 27% included patient representation. In all, 6.7%, 21.3%, and 71.9% of recommendations were based on high, moderate, and low-quality evidence, respectively. Twenty-seven percent, 23.6%, and 49.4% of recommendations were strong, weak/conditional, and did not provide a strength, respectively. The proportion of high-quality evidence ( P =0.28) and strong recommendations ( P =0.41) did not significantly differ across societies.

CONCLUSIONS

Many guidelines do not provide recommendations on key aspects of preventative care in IBD. As over 70% of recommendations are based on low-quality evidence, further studies on preventative care in IBD are warranted to improve the overall quality of evidence.

Thiopurines are an independent risk factor for active tuberculosis in inflammatory bowel disease patients

The use of thiopurines is an independent risk factor for active tuberculosis in patients with inflammatory bowel disease.

Diagnostic accuracy of different cross-sectional imaging techniques for disease location and activity in Crohn's disease and external validation and comparison of MARIAs and IBUS-SAS

PURPOSE

The comparative accuracy of cross-sectional imaging techniques for evaluating Crohn's disease (CD) remains uncertain. This study aimed to assess diagnostic accuracy of disease location and activity in different cross-sectional images and validate and compare International Bowel Ultrasound Segmental Activity Score (IBUS-SAS) and Simplified Magnetic Resonance Index of Activity (MARIAs).

METHODS

CD patients were retrospectively included from August 2018 to May 2021. We compared accuracy of B-mode intestinal ultrasound (B-IUS), computed tomography enterography (CTE), and magnetic resonance enterography (MRE) for the identification of disease location. Meanwhile, disease activity was compared on B-IUS, color Doppler imaging, CTE, and MRE. ROC analyses were used to validate MARIAs and IBUS-SAS. Spearman rank correlation was performed to evaluate the relationships between MARIAs/IBUS-SAS and CDAI, SES-CD, and inflammatory indicators.

RESULTS

A total of 115 CD patients were evaluated. The diagnostic accuracy of MRE in detecting small bowel disease was superior to that of B-IUS/CTE, showing sensitivity (89.3%), specificity (71.4%), and AUC (0.820). B-IUS had the highest sensitivity (81.2%), specificity (84.8%), and AUC (0.830) for detecting terminal ileal lesions. The diagnostic accuracy for colonic disease and disease activity was not significantly different among these techniques. In the validation of IBUS-SAS, the AUC was 0.860, with an optimal cutoff value to predict active disease of 46.7. MARIAs and IBUS-SAS showed no significant differences in the correlations of CDAI, SES-CD, and inflammatory indicators.

CONCLUSION

MRE and B-IUS are more sensitive for detecting small bowel CD and terminal ileal CD, respectively. IBUS-SAS has potential for precisely defining CD activity.

Management of biologics in pregnant, lactating patients with inflammatory bowel disease and the impact on neonatal vaccination: A systematic review of clinical practice guidelines and consensus statements

WHAT IS KNOWN AND OBJECTIVE

The management of biological agents during pregnancy poses challenges as maternal and infant safety must be addressed. This study aims to compare the recommendations of existing guidelines on managing the use of biologics during pregnancy, lactation for patients with inflammatory bowel disease, and the influence on neonatal vaccination.

METHODS

The PubMed, EMBASE, China National Knowledge Infrastructure, Wanfang database, China Science and Technology Journal Database and China Biomedical Database were systematically searched from the inception date to 11 May 2022, to screen all relevant guidelines. Quality assessment was performed using the guideline methodology reporting tool AGREE II.

RESULTS AND DISCUSSION

Fourteen guidelines and consensus statements with detailed recommendations were included. All guidance documents cover management comments during pregnancy, and most consider that biologics can be given safely during pregnancy but require suspension at the right time to protect the foetus. However, the roles of vedolizumab and ustekinumab are disputed. Five documents guide lactation and the use of most biologics during lactation is safe, but no guidelines recommend vedolizumab. Six papers provide recommendations for newborns' vaccination, suggesting a delay in infants' live vaccination schedule if their mothers are treated with biologics.

WHAT IS NEW AND CONCLUSION

Our study concluded that future guidelines could consider incorporating newer, more robust evidence to update recommendations. The development of future guidelines needs to consider the involvement of multidisciplinary experts, adequately report on the evidence retrieval process, and provide strategies for implementation. Besides, more research is needed to explore the use of biologics during pregnancy and lactation in patients with inflammatory bowel disease.

A broad cuproptosis landscape in inflammatory bowel disease

Background

Cuproptosis, a genetic process of copper-dependent cell death linked to mitochondria respiration, demonstrates its correlation with inhibiting tumoral angiogenesis and motility. Recent studies have developed systematic bioinformatics frameworks to identify the association of cuproptosis with tumors but any non-neoplastic diseases. Therefore, against the background of an increased incidence of inflammatory bowel disease (IBD), the landscape of cuproptosis regulation in IBD is a critical need to be investigated.

Methods

The differentially expressed cuproptosis-related genes (DECRGs) were identified with human sequencing profiles for four inflammatory digestive disorders. Another four independent IBD datasets from GEO were used as a validation cohort. And experimental mice model provides another validation method. Using single sample gene set enrichment analysis (ssGSEA), receiver operating characteristic (ROC) curve, CIBERSORT, and consensus clustering algorithms, we explored the association between immune score and cuproptosis-related genes, as well as the diagnostic value of these genes. Molecular docking screened potential interaction of IBD drugs with the structural regulator by Autodock Vina.

Results

Cuproptosis-related regulators exhibited extensive differential expression in Crohn's Disease (CD), Ulcerative Colitis (UC), Celiac Disease (CEL), and IBD-induced cancer (IBD-CA) that share common differential genes (PDHA1, DBT, DLAT, LIAS). The differential expression of DECRGs was reverified in the validated cohort and immunohistochemistry assay. Moreover, the cell signaling pathways and ontology mainly focused on the mitochondrial respiratory function, which was highly enriched in Gene set enrichment analysis (GSEA). According to ssGSEA and ROC, when considering the four regulators, which showed robust association with immune infiltration in IBD, the area under the ROC (AUC) was 0.743. In addition, two clusters of consensus clustering based on the four regulators exhibit different immune phenotypes. According to molecular docking results, methotrexate gained the highest binding affinity to the main chain of key cuproptosis-related regulators compared with the remaining ten drugs.

Conclusion

Cuproptosis-related regulators were widely linked to risk variants, immune cells, immune function, and drug efficacy in IBD. Regulation of cuproptosis may deeply influence the occurrence and development of patients with IBD.

Methotrexate showed efficacy both in Crohn’s disease and ulcerative colitis, predictors of surgery were identified in patients initially treated with methotrexate monotherapy

Objective: This study aimed to evaluate methotrexate efficacy in patients with Crohn’s disease (CD) and ulcerative colitis (UC), and identify predictors of surgery for patients who were initially treated with methotrexate monotherapy.

Design: We performed a retrospective analysis of 34,860 patients with inflammatory bowel disease (IBD) in the IBD Bioresource (United Kingdom) prior to 9 November 2021. Logistic regression was used to identify factors associated with methotrexate efficacy. The data were randomly stratified into training and testing sets (7:3). Nomograms were developed based on Cox regression analysis outcomes. The predictive accuracy and discriminative ability were determined using the concordance index (C-index) and calibration curves.

Results: Overall, 1,042 patients (CD: 791, UC: 251) were included. Independent factors associated with effective methotrexate monotherapy were younger age at diagnosis, latest therapy period, exclusive upper gastrointestinal tract disease (for CD), and longer duration between diagnosis and methotrexate initiation (for UC). For CD, predictors in the nomogram were gender, treatment era, tolerance, lesion site, perianal involvement, disease behaviour, and biologics requirements (C-index: 0.711 and 0.732 for training and validation cohorts, respectively). For UC, the factors were age at diagnosis and sex (C-index: 0.784 and 0.690 for training and validation cohorts, respectively). Calibration curves demonstrated good agreement between predictions and actual observations.

Thiopurine S-Methyltransferase Polymorphisms Predict Hepatotoxicity in Azathioprine-Treated Patients with Autoimmune Diseases

Thiopurine methyltransferase (TPMT) is the rate-limiting enzyme in Azathioprine (AZA) metabolization. Although studies have discussed the association between the TPMT polymorphisms and myelosuppression, the data about the relationship between TPMT genotypes and hepatoxicity in Asian patients remain limited. This study investigated the correlation between TPMT polymorphisms and AZA-related hepatotoxicity. This study enrolled the patients who had prior exposure to AZA from the Taichung Veterans General Hospital (TCVGH)-Taiwan Precision Medicine Initiative (TPMI) cohort. Genetic variants were determined using a single nucleotide polymorphism (SNP) array. Participants were accordingly categorized into normal metabolizer (NM) and non-normal metabolizer (non-NM) groups. From the TCVGH-TPMI cohort, we included 50 TPMT non-NM patients, including 1 poor metabolizer (PM), 49 intermediate metabolizers (IMs), and 1000 NM patients. The non-NM genotype was associated with hepatotoxicity compared with the NM genotype (hazard ratio (HR): 3.85, 95% confidence interval (CI): 1.83−8.10). In the non-NM group, the 3-year cumulative incidence of hepatotoxicity was higher than that in the NM group at 8.5% in the first year and 18.6% in the second and third years (p < 0.001). A TPMT non-NM genotype was associated with the occurrence of hepatotoxicity following AZA therapy. Preemptive testing helps individualize AZA therapy by minimizing the risk of hepatotoxicity.

Presume Why Probiotics May Not Provide Protection in Inflammatory Bowel Disease through an Azoxymethane and Dextran Sodium Sulfate Murine Model

Recent studies have shown dysbiosis is associated with inflammatory bowel disease (IBD). However, trying to restore microbial diversity via fecal microbiota transplantation (FMT) or probiotic intervention fails to achieve clinical benefit in IBD patients. We performed a probiotic intervention on a simulated IBD murine model to clarify their relationship. IBD was simulated by the protocol of azoxymethane and dextran sodium sulfate (AOM/DSS) to set up a colitis and colitis-associated neoplasm model on BALB/c mice. A single probiotic intervention using Clostridium butyricum Miyairi (CBM) on AOM/DSS mice to clarify the role of probiotic in colitis, colitis-associated neoplasm, gut microbiota, and immune cytokines was performed. We found dysbiosis occurred in AOM/DSS mice. The CBM intervention on AOM/DSS mice failed to improve colitis and colitis-associated neoplasms but changed microbial composition and unexpectedly increased expression of proinflammatory IL-17A in rectal tissue. We hypothesized that the probiotic intervention caused dysbiosis. To clarify the result, we performed inverse FMT using feces from AOM/DSS mice to normal recipients to validate the pathogenic effect of dysbiosis from AOM/DSS mice and found mice on inverse FMT did develop colitis and colon neoplasms. We presumed the probiotic intervention to some extent caused dysbiosis as inverse FMT. The role of probiotics in IBD requires further elucidation.

Renal and Urological Disorders Associated With Inflammatory Bowel Disease

Renal and urinary tract complications related to inflammatory bowel disease (IBD) have been relatively understudied in the literature compared with other extraintestinal manifestations. Presentation of these renal manifestations can be subtle, and their detection is complicated by a lack of clarity regarding the optimal screening and routine monitoring of renal function in IBD patients. Urolithiasis is the most common manifestation. Penetrating Crohn's disease involving the genitourinary system as an extraintestinal complication is rare but associated with considerable morbidity. Some biologic agents used to treat IBD have been implicated in progressive renal impairment, although differentiating between drug-related side effects and deteriorating kidney function due to extraintestinal manifestations can be challenging. The most common findings on renal biopsy of IBD patients with renal injury are tubulointerstitial nephritis and IgA nephropathy, the former also being associated with drug-induced nephrotoxicity related to IBD medication. Amyloidosis, albeit rare, must be diagnosed early to reduce the chance of progression to renal failure. In this review, we evaluate the key literature relating to renal and urological involvement in IBD and emphasize the high index of suspicion required for the prompt diagnosis and treatment of these manifestations and complications, considering the potential severity and implications of acute or chronic loss of renal function. We also provide suggestions for future research priorities.

Review article: latent tuberculosis in patients with inflammatory bowel diseases receiving immunosuppression-risks, screening, diagnosis and management

BACKGROUND

One quarter of the world's population has latent tuberculosis infection (LTBI). Systemic immunosuppression is a risk factor for LTBI reactivation and the development of active tuberculosis. Such reactivation carries a risk of significant morbidity and mortality. Despite the increasing global incidence of inflammatory bowel disease (IBD) and the use of immune-based therapies, current guidelines on the testing and treatment of LTBI in patients with IBD are haphazard with a paucity of evidence.

AIM

To review the screening, diagnostic practices and medical management of LTBI in patients with IBD.

METHODS

Published literature was reviewed, and recommendations for testing and treatment were synthesised by experts in both infectious diseases and IBD.

RESULTS

Screening for LTBI should be performed proactively and includes assessment of risk factors, an interferon-gamma releasing assay or tuberculin skin test and chest X-ray. LTBI treatment in patients with IBD is scenario-dependent, related to geographical endemicity, travel and other factors. Ideally, LTBI therapy should be used prior to immune suppression but can be applied concurrently where urgent IBD medical treatment is required. Management is best directed by a multidisciplinary team involving gastroenterologists, infectious diseases specialists and pharmacists. Ongoing surveillance is recommended during therapy. Newer LTBI therapies show promise, but medication interactions need to be considered. There are major gaps in evidence, particularly with specific newer therapeutic approaches to IBD.

CONCLUSIONS

Proactive screening for LTBI is essential in patients with IBD undergoing immune-suppressing therapy and several therapeutic strategies are available. Reporting of real-world experience is essential to refining current management recommendations.

Indications, Postoperative Management, and Long-term Prognosis of Crohn's Disease After Ileocecal Resection: A Multicenter Study Comparing the East and West

BACKGROUND

The Crohn's disease (CD) phenotype differs between Asian and Western countries and may affect disease management, including decisions on surgery. This study aimed to compare the indications, postoperative management, and long-term prognosis after ileocecal resection (ICR) in Hong Kong (HK) and the Netherlands (NL).

METHODS

CD patients with primary ICR between 2000 and 2019 were included. The endpoints were endoscopic (Rutgeerts score ≥i2b and/or radiologic recurrence), clinical (start or switch of inflammatory bowel disease medication), and surgical recurrences. Cumulative incidences of recurrence were estimated with a Bayesian multivariable proportional hazards model.

RESULTS

Eighty HK and 822 NL patients were included. The most common indication for ICR was penetrating disease (HK: 32.5%, NL: 22.5%) in HK vs stricturing disease (HK: 32.5%, NL: 48.8%) in the NL (P < .001). Postoperative prophylaxis was prescribed to 65 (81.3%) HK patients (28 [35.0%] aminosalicylates [5-aminosalicylic acid]; 30 [37.5%] immunomodulators; 0 biologicals) vs 388 (47.1%) NL patients (67 [8.2%] 5-aminosalicylic acid; 187 [22.8%] immunomodulators; 69 [8.4%] biologicals; 50 [6.1%] combination therapy) (P < .001). Endoscopic or radiologic evaluation within 18 months was performed in 36.3% HK vs 64.1% NL (P < .001) patients. No differences between both populations were observed for endoscopic (hazard ratio [HR], 0.53; 95% confidence interval [CI], 0.24-1.21), clinical (HR, 0.91; 95% CI, 0.62-1.32), or surgical (HR, 0.61; 95% CI, 0.31-1.13) recurrence risks.

CONCLUSION

The main indication for ICR in CD patients is penetrating disease in HK patients and stricturing disease in NL patients. Although considerable pre- and postoperative management differences were observed between the two geographical areas, the long-term prognosis after ICR is similar.

Prevalence and predictors of non-alcoholic liver disease on MRI among patients with Crohn's disease

BACKGROUND

It has been documented that Crohn's disease (CD) patients were prone to develop non-alcoholic liver fatty liver disease (NAFLD) with less metabolic factors. Our purpose is to investigate the prevalence, clinical characteristics and possible indicators for NAFLD in a cohort of Chinese patients with CD.

METHODS

Established CD patients who underwent magnetic resonance enterography (MRE) at the gastroenterology unit of our hospital were consecutively enrolled between June 2018 and May 2020. The diagnosis of NAFLD was made by magnetic resonance proton density fat fraction (MR-PDFF) maps. Medical records during hospitalization were collected and examined by univariate and multivariate analyses. Then a predictive model was constructed based on logistic regression analysis to evaluate the risk of developing NAFLD.

RESULTS

A total of 340 CD subjects were enrolled in this study, 83 (24.4%) suffered from NAFLD. Compared with those without NAFLD, patients with NAFLD showed longer disease duration, higher body mass index (BMI), more frequent use of corticosteroid and pronouncedly elevated liver function tests. The comparison showed no difference in terms of prolonged anti tumor necrosis factor-α (TNF-α) use (> 54w). Multivariate analysis demonstrated that BMI, serum transaminase, pre-albumin and disease duration could independently predict hepatic steatosis.

CONCLUSION

NAFLD is frequent in chronic CD patients, while long term use of anti TNF-α seems to have no impact on the development of NAFLD in this population. The model incorporating duration, serum transaminase and body mass index presented as a clinical nomogram could well predict the risk of NAFLD in patient with CD.

Telemonitoring for patients with inflammatory bowel disease amid the COVID-19 pandemic—A cost-effectiveness analysis

Background and aim

COVID-19 pandemic burdens the healthcare systems, causes healthcare avoidance, and might worsen the outcomes of inflammatory bowel disease (IBD) management. We aimed to estimate the impact of pandemic-related avoidance on outpatient IBD management, and the cost-effectiveness of adding telemonitoring during pandemic from the perspective of Hong Kong public healthcare provider.

Methods

The study was performed by a decision-analytic model to estimate the quality-adjusted life-years (QALYs) and cost of care for IBD patients before and during the pandemic, and to compare the cost and QALYs of adding telemonitoring to standard care (SC-TM) versus standard care alone (SC) for IBD patients during the pandemic. The sources of model inputs included publications (retrieved from literature search) and public data. Sensitivity analyses were conducted to examine the robustness of base-case results.

Results

Standard care with pandemic-related avoidance (versus without avoidance) lost 0.0026 QALYs at higher cost (by USD43). The 10,000 Monte Carlo simulations found standard care with pandemic-related avoidance lost QALYs and incurred higher cost in 100% and 96.82% of the time, respectively. Compared with the SC group, the SC-TM group saved 0.0248 QALYs and reduced cost by USD799. Monte Carlo simulations showed the SC-TM group gained higher QALYs at lower cost in 100% of 10,000 simulations.

Conclusions

Standard care for IBD patients during pandemic with healthcare avoidance appears to worsen treatment outcomes at higher cost and lowered QALYs. The addition of telemonitoring to standard care seems to gain higher QALYs and reduce cost, and is therefore a potential cost-effective strategy for IBD management during the pandemic.

Is There a Best First Line Biological/Small Molecule in IBD: Are We Ready for Sequencing?

Inflammatory bowel disease (IBD) is a chronic, life-long inflammatory condition of the gastrointestinal tract. Treatment strategy depends on the severity of the disease course. IBD physicians need to be aware of the life-long treatment options available. The goal is not only to achieve clinical remission but to halt or stabilize the chronic inflammation in the intestines to prevent further structural damage. Therefore, the use of early biologic therapy is recommended in moderate-to-severe IBD patients. However, in the last decade, use of therapeutic drug monitoring has increased considerably, opening an opportunity for sequencing. This review summarizes the available evidence on biologic and small molecules therapy in Crohn's disease (CD) and ulcerative colitis (UC) in different clinical scenarios, including perianal CD, the elderly, extra intestinal manifestations, and pregnancy.

Colorectal Cancer in Inflammatory Bowel Disease: Mechanisms and Management

Patients with inflammatory bowel disease (IBD) are at increased risk of developing colorectal cancer (CRC), despite decreases in CRC incidence in recent years. Chronic inflammation is the driver of neoplastic progression, resulting in dysplastic precursor lesions that may arise in multiple areas of the colon through a process of field cancerization. Colitis-associated CRC shares many molecular similarities with sporadic CRC, and preclinical investigations have demonstrated a potential role for the microbiome in concert with the host immune system in the development of colitis-associated colorectal cancer (CAC). Some unique molecular differences occur in CAC, but their role in the pathogenesis and behavior of inflammation-associated cancers remains to be elucidated. Nonconventional types of dysplasia have been increasingly recognized, but their natural history is not well defined, and they have not been incorporated into surveillance algorithms. The concept of cumulative inflammatory burden highlights the importance of considering histologic inflammation over time as an important risk factor for CAC. Dysplasia is arguably the most important risk factor for developing CAC, and advances have been made in the endoscopic detection and removal of precancerous lesions, thereby deferring or avoiding surgical resection. Some of the agents used to treat IBD are chemopreventive. It is hoped that by gaining better control of the underlying inflammation with newer medications and better endoscopic detection and management, a more sophisticated appreciation of clinicopathologic risk factors, and growing awareness of the genetic, immunologic, and environmental causes of colitis- associated neoplasia, that colitis-associated colorectal neoplasia will become even more predictable and manageable in the coming years.

Randomised clinical trial: dose optimising strategy by NUDT15 genotyping reduces leucopenia during thiopurine treatment of Crohn's disease

INTRODUCTION

Thiopurine S-methyltransferase (TPTM) is a well known biomarker for thiopurine-induced leucopenia, which has limited value in Asia. Instead, NUDT15 C415T is a promising predictor in Asia.

AIMS

To explore whether an optimised strategy based on NUDT15 C415T genotypes affects thiopurine-induced leucopenia, as well as efficacy in Chinese patients with Crohn's disease.

METHODS

Patients with Crohn's disease and indications for thiopurines were included from two hospitals in China. They were randomly assigned to either the intervention or the control group. In the intervention group, those with genotype CC received a standard dose (control group), those with CT genotype received 50% of the standard dose, those with TT genotype received alternative drugs. The primary endpoint was thiopurine-induced leucopenia (<3.5 × 10⁹ /L). Secondary outcomes were the incidence of other adverse events and the efficacy for maintaining steroid-free remission at week 36.

RESULTS

The rate of thiopurine-induced leucopenia was lower in the intervention group (n = 52) than in the control group (n = 66) (23.7% vs 32.4%, P = 0.049, RR = 0.73, 95% CI 0.53-1.00). In CT subgroup, the incidence of leucopenia in the intervention group (n = 10) was significantly lower than in the control group (n = 28) (31.3% vs 65.1%, RR = 0.48, 95% CI 0.28-0.84). Neither other adverse events nor treatment efficacy was significantly different between the two groups during follow-up.

CONCLUSIONS

Among Chinese patients with Crohn's disease, dose optimisation by NUDT15 C415T reduced the rate of thiopurine-induced leucopenia, without significant influence on efficacy. Using 50% dose reduction for heterozygotes, and alternative drugs for homozygotes, are practicable strategies. Clinical trial number: NCT02929706.

Association Between Genetic Polymorphisms of Metabolic Enzymes and Azathioprine-Induced Myelosuppression in 1,419 Chinese Patients: A Retrospective Study

The aim of this study was to investigate the correlation between genetic polymorphisms of azathioprine-metabolizing enzymes and adverse reactions of myelosuppression. To this end, a retrospective analysis was performed on 1,419 Chinese patients involving 40 different diseases and 3 genes: ITPA (94C>A), TPMT*3 (T>C), and NUDT15 (415C>T). Strict inclusion and exclusion criteria were established to collect the relative cases, and the correlation between azathioprine and myelosuppression was evaluated by adverse drug reaction criteria. The mutation rates of the three genes were 29.32, 3.73, and 21.92% and grades I to IV myelosuppression occurred in 54 (9.28%) of the 582 patients who took azathioprine. The highest proportion of myelosuppression was observed in 5 of the 6 (83.33%) patients carrying the NUDT15 (415C>T) TT genotype and 12 of the 102 (11.76%) patients carrying the NUDT15 (415C>T) CT genotype. Only the NUDT15 (415C>T) polymorphism was found to be associated with the adverse effects of azathioprine-induced myelosuppression (odds ratio [OR], 51.818; 95% CI, 5.280–508.556; p = 0.001), which suggested that the NUDT15 (415C>T) polymorphism could be an influencing factor of azathioprine-induced myelosuppression in the Chinese population. Epistatic interactions between ITPA (94C>A) and NUDT15 (415C>T) affect the occurrence of myelosuppression. Thus, it is recommended that the genotype of NUDT15 (415C>T) and ITPA (94C>A) be checked before administration, and azathioprine should be avoided in patients carrying a homozygous NUDT15 (415C>T) mutation. This study is the first to investigate the association between genetic polymorphisms of these three azathioprine-metabolizing enzymes and myelosuppression in a large number of cases with a diverse range of diseases.

The Kobe University Human Intestinal Microbiota Model for gut intervention studies

The human gut harbors a complex microbial community that performs a range of metabolic, physiological, and immunological functions. The host and its inhabiting microorganisms are often referred to as a "superorganism." Dysbiosis of gut microflora has been associated with the pathogenesis of intestinal disorders including inflammatory bowel disease, colorectal cancer, and extra-intestinal disorders such as cardiovascular disease. Therefore, gut microbiome interventions are important for the prevention and treatment of diseases. However, ethical, economic, scientific, and time constraints limit the outcome of human intervention or animal studies targeting gut microbiota. We recently developed an in vitro batch fermentation model (the Kobe University Human Intestinal Microbiota Model, KUHIMM) that is capable of hosting a majority of gut microbial species in humans and also detects the metabolites produced by microorganisms in real time. In this mini review, we elucidated the characteristics of the KUHIMM and its applicability in analyzing the effect of diet, drugs, probiotics, and prebiotics on intestinal bacteria. In addition, we introduce as examples its application to disease models, such as ulcerative colitis, in which intestinal bacteria are intricately involved in the process of pathogenesis. We also discuss the potential of the KUHIMM in precision medicine. KEY POINTS: • In vitro gut fermentation model to simulate human colonic microbiota • Screening of potential prebiotics and probiotic candidates in healthy model • Construction of disease models of ulcerative colitis and coronary artery disease.