Long-term course of Crohn's disease in Japan: Incidence of complications, cumulative rate of initial surgery, and risk factors at diagnosis for initial surgery

Pediatric stricturing Crohn's disease

Crohn's disease (CD) is a chronic inflammatory disease of the digestive tract. The incidence of pediatric CD is increasing and is currently 2.5-11.4 per 100000 world-wide. Notably, approximately 25% of children with CD develop stricturing CD (SCD) that requires intervention. Symptomatic stricturing diseases refractory to pharmacological management frequently require non-pharmacological interventions. Non-pharmacological therapeutic strategies include endoscopic balloon dilatation, stricturoplasty, and surgical resection of the strictured segment. However, strictures tend to recur postoperatively regardless of treatment modality. The lifetime risk of surgery in patients with childhood SCD remains at 50%-90%. Thus, new and emerging strategies, advanced diagnostic tools, and minimally invasive approaches are under investigation to improve the outcomes and overall quality of life of pediatric patients with SCD.

Role of Oncostatin M in the prognosis of inflammatory bowel disease: A meta-analysis

BACKGROUND

Oncostatin M (OSM) is a pleiotropic cytokine which is implicated in the pathogenesis of inflammatory bowel disease (IBD).

AIM

To evaluate the prognostic role of OSM in IBD patients.

METHODS

Literature search was conducted in electronic databases (Google Scholar, Embase, PubMed, Science Direct, Springer, and Wiley). Studies were selected if they reported prognostic information about OSM in IBD patients. Outcome data were synthesized, and meta-analyses were performed to estimate standardized mean differences (SMDs) in OSM levels between treatment responders and non-responders and to seek overall correlations of OSM with other inflammatory biomarkers.

RESULTS

Sixteen studies (818 Crohn's disease and 686 ulcerative colitis patients treated with anti-tumor necrosis factor-based therapies) were included. OSM levels were associated with IBD severity. A meta-analysis found significantly higher OSM levels in non-responders than in responders to therapy [SMD 0.80 (0.33, 1.27); P = 0.001], in non-remitters than in remitters [SMD 0.75 (95%CI: 0.35 to 1.16); P < 0.0001] and in patients with no mucosal healing than in those with mucosal healing [SMD 0.63 (0.30, 0.95); P < 0.0001]. Area under receiver operator curve values showed considerable variability between studies but in general higher OSM levels were associated with poor prognosis. OSM had significant correlations with Simple Endoscopic Score of Crohn's disease [r = 0.47 (95%CI: 0.25 to 0.64); P < 0.0001], Mayo Endoscopic Score [r = 0.35 (95%CI: 0.28 to 0.41); P < 0.0001], fecal calprotectin [r = 0.19 (95%CI: 0.08 to 0.3); P = 0.001], C-reactive protein [r = 0.25 (95%CI: 0.11 to 0.39); P < 0.0001], and platelet count [r = 0.28 (95%CI: 0.17 to 0.39); P < 0.0001].

CONCLUSION

OSM is a potential candidate for determining the severity of disease and predicting the outcomes of anti-tumor necrosis factor-based therapies in IBD patients.

Imaging of Strictures in Crohn's Disease

Crohn's disease (CD) is a chronic inflammation of the digestive tract, and it frequently affects young patients. It can involve any intestinal segment, even though it frequently affects the distal ileum. Up to 80% of patients with CD present with inflammatory behavior, and 5% to 28% develop stricturing disease. Based on the predominant mechanism causing them, strictures can be categorized as inflammatory, fibrotic, or mixed. Determining the relative amounts of inflammation and fibrosis in a stricture can influence treatment decisions. Imaging is an extremely useful tool in patients with small bowel stricturing CD to confirm the diagnosis and to evaluate disease characteristics, usually using CT or MRI. The aim of this paper is to describe how imaging can evaluate a patient with small bowel CD stricture.

Maintenance of complete mucosal healing is associated with avoiding restenosis after endoscopic balloon dilation of Crohn's disease-related small intestinal strictures

Background

Endoscopic balloon dilation (EBD) is an effective, minimally invasive treatment for Crohn's disease (CD) related intestinal strictures. However, restenosis frequently occurs and requires repetitive EBD or surgical resection. Since previous studies could not evaluate restenosis based on stricture diameter, factors affecting restenosis after EBD were unclear. This study aimed to identify these factors by precisely measuring the diameter of small intestinal strictures in patients with CD.

Methods

This single-center retrospective study enrolled patients with CD with de novo small intestinal strictures who underwent two double-balloon enteroscopy sessions (EBD and follow-up) between January 2016 and October 2021. Clinical and endoscopic data were obtained from electronic medical records. A calibrated small-caliber-tip transparent hood was used to precisely measure stricture diameters. Multivariate analysis was performed to identify factors associated with restenosis.

Results

Forty-eight patients (37 male) were analyzed. The total number of strictures detected decreased from 162 to 143. The mean diameter of all strictures and the narrowest stricture in each patient increased significantly from 8.6 to 9.8 mm and from 7.6 to 8.7 mm, respectively. Thirty-two (67%) patients developed endoscopic restenosis. Multivariate analysis showed that the presence of ulcers at the follow-up session was a risk factor for restenosis (odds ratio 9.4, p = 0.01). Patients with complete mucosal healing at both sessions (n = 21) showed significant improvement in the narrowest stricture (+1.7 mm, p = 0.001).

Conclusions

Maintenance of complete mucosal healing is significantly associated with avoiding restenosis after EBD in CD-related small intestinal strictures.

Predictive factors of the clinical efficacy of ustekinumab in patients with refractory Crohn's disease: tertiary centers experience in Japan

PURPOSE

Therapeutic efficacy of ustekinumab in the real-world data is limited in patients with refractory Crohn's disease (CD). In addition, factors predictive of better therapeutic efficacy of ustekinumab remains unsolved in CD. We aimed to evaluate therapeutic efficacy of ustekinumab in patients with refractory CD and to identify the factors associated with the efficacy of ustekinumab.

METHODS

We retrospectively analyzed the clinical data of 72 patients treated with ustekinumab for refractory CD. Therapeutic efficacy was assessed at weeks 8, 26, 52, and 104 on the basis of dual remission, defined as the combination of Crohn's Disease Activity Index < 150 and CRP < 0.3 mg/dL, and factors predictive of the induction and maintenance of dual remission were investigated. The cumulative continuation rates and safety of ustekinumab were assessed.

RESULTS

The dual remission rates at weeks 8, 26, 52, and 104 were 31.9%, 37.9%, 47.5%, and 42.6%, respectively. A short disease duration (≤ 2 years) and higher baseline serum albumin levels (≥ 3.1 g/dL) were positively associated with dual remission at weeks 8 and 52. Meanwhile, higher serum CRP levels (≥ 1.19 mg/dL) were negatively associated with dual remission at week 8. The cumulative ustekinumab continuation rate was favorable, and no severe adverse events were found.

CONCLUSION

A short disease duration and higher baseline serum albumin levels might be predictive of favorable therapeutic efficacy of ustekinumab in refractory CD. Induction efficacy appears to be lower in patients with higher serum CRP levels.

Perioperative optimization of Crohn's disease

Crohn's disease (CD) is a chronic inflammatory disease mainly affecting the gastrointestinal tract. With the increased availability of modalities in the last two decades, the treatment of CD has advanced remarkably. Although medical treatment is the mainstay of therapy, most patients require surgery during the course of their illness, especially those who experience complications. Nutritional optimization and ERAS implementation are crucial for patients with CD who require surgical intervention to reduce postoperative complications. The increased surgical risk was found to be associated with the use of corticosteroids, but the association of surgical risk with immunomodulators, biologic therapy, such as anti-TNF mediations, anti-integrin medications, and anti-IL 12/23 was low in certainty. Decisions about preoperative medication must be made on an individual case-dependent basis. Preoperative imaging studies can assist in the planning of appropriate surgical strategies and approaches. However, patients must be informed of any alterations to their treatment. In summary, the management of perioperative medications and surgery-related decision-making should be individualized and patient-centered based on a multidisciplinary approach.

Mucosal healing of small intestinal stricture is associated with improved prognosis post-dilation in Crohn's disease

BACKGROUND

Small intestinal stricture is a major cause for surgery in Crohn's disease (CD). Endoscopic balloon dilation (EBD) is performed for small intestinal strictures to avoid surgery, often repeatedly. However, factors that are associated with prognosis after EBD of small intestinal strictures remain poorly investigated. Mucosal healing is the therapeutic target in CD. We aimed to investigate the impact of mucosal healing defined by the presence of ulcers at the small intestinal stricture site on the prognosis of EBD in CD patients.

METHODS

We retrospectively included patients with CD who underwent initial EBD for endoscopically impassable small intestinal strictures from January 2012 to March 2020 at a single center. The association between presence of ulcer at the stricture site and surgery after EBD was examined by Cox proportional hazards model.

RESULTS

Of the 98 patients included, 63 (64.3%) had ulcer at the stricture site. 20 (31.7%) of these patients underwent surgery for the stricture in due course, whereas 4 (11.4%) of the patients without ulcer of the stricture underwent surgery. In multivariate analysis, patients with ulcer of the stricture had a significantly higher risk for surgery than those without ulcer (hazard ratio 4.84; 95% confidence interval 1.58-14.79).

CONCLUSION

Mucosal healing at the stricture site indicated a favorable prognosis after EBD for small intestinal strictures in CD.

Long-term outcomes of endoscopic balloon dilation for intestinal strictures in patients with Crohn's disease during maintenance treatment with anti-tumor necrosis factor alpha antibodies

BACKGROUND AND AIMS

Efficacy of endoscopic balloon dilation (EBD) for intestinal strictures in patients with Crohn's disease (CD) receiving anti-tumor necrosis factor alpha antibodies (anti-TNF) as maintenance therapy is unclear. We investigated the long-term efficacy and safety of EBD for intestinal strictures in patients with CD receiving anti-TNF.

METHODS

We retrospectively analyzed data from patients with CD who received anti-TNF as maintenance therapy from 2008 to 2017, underwent EBD, and were followed up for ≥6 months. The primary endpoint was the cumulative surgery-free rate. The main secondary endpoints were technical success, repeat EBD rate, risk factors affecting surgical outcomes, and safety.

RESULTS

Seventy-two patients with CD were assessed. The median observation period after EBD was 50 months. The technical success rate was 67%. The 3- and 5-year cumulative surgery-free rates were 81.1% and 73.5%, respectively. The repeat EBD rate was 74%. Multivariable analyses showed that risk factors affecting surgical outcomes were age at disease onset ≤16 years (hazard ratio 3.69; 95% confidence interval 1.36-10.01; P = 0.011). Serious complications requiring surgery developed in three patients.

CONCLUSIONS

Endoscopic balloon dilation was an effective and safe short-term treatment and a useful long-term treatment for CD patients with intestinal strictures receiving anti-TNF as maintenance therapy.

What Are the Different Phenotypes of Inflammatory Bowel Disease in Asia?

The burden of inflammatory bowel disease (IBD) in Asia has been increasing over the past decades. Although patients with IBD show heterogenous phenotypes depending on the individual characteristics, no significant differences have been established in the IBD phenotypes of Western and Asian populations. However, despite the much lower incidence of IBD in Asia than in Western countries, the incidence has been rapidly increasing in Asia while remaining stable in Western countries. The incidence of ulcerative colitis (UC) showed an earlier and a more marked increase than the incidence of Crohn disease (CD), but the UC-to-CD ratio has recently decreased because of a relative increase in the incidence of CD in Asia. While CD shows a significant male predominance, UC only shows a slight male predominance. A recent study reported that the incidence of IBD in Asia showed a bimodal age distribution with increasing IBD prevalence, similar to the findings of Western studies. CD in Asian patients, especially those in East Asia, is characterized by ileocolonic involvement and perianal fistula. The frequency of extraintestinal manifestations, including primary sclerosing cholangitis, appears to be lower in Asia, but this finding should be interpreted with caution due to the transient and nonspecific nature of these manifestations. Although familial aggregation is lower in East Asia, it may also be explained by the low prevalence of IBD in Asia. Thus, more studies should focus on the differences in phenotypes in Asian IBD patients versus Western patients.

A review on the current status and definitions of activity indices in inflammatory bowel disease: how to use indices for precise evaluation

Many clinical trials have been conducted for inflammatory bowel disease (IBD), so various clinical indices (CIs) and endoscopic indices (EIs) have also been evaluated. However, recently, with the progress of IBD management, review of established indices from previous studies, and establishment of new indices, the landscape of the use of indices in clinical trials have changed. We investigated the number and frequency of the indices adapted in recent clinical trials for ulcerative colitis (CI and EI) and Crohn's disease (CI, EI, index related to magnetic resonance imaging, index for evaluating patient-reported outcomes, and health-related quality of life). Based on the results, we selected representative indices and further reviewed their content and characteristics. Moreover, various definitions, including clinical and endoscopic response or remission, have been described by means of representative indices in clinical trials.

Predictors of necessity for endoscopic balloon dilatation in patients with Crohn's disease-related small bowel stenosis

BACKGROUND AND AIM

In patients with Crohn's disease (CD) and small bowel stenosis, endoscopic balloon dilation (EBD) is considered to be useful in improving stenotic symptoms and avoiding surgery. However, it carries risks such as bleeding and perforation. The aim of this study was to identify the indications for endoscopic intervention in patients with CD and small bowel stenosis.

METHODS

From November 2007 to March 2020, 143 CD patients with small bowel stenosis were enrolled in this study. We identified the factors associated with not requiring endoscopic intervention during long-term follow-up of these patients.

RESULTS

Forty of the 143 patients had abdominal symptoms of stenosis and had undergone EBD, whereas the remaining 103 were asymptomatic and had not undergone endoscopic intervention. During long-term follow-up, 95 of those 103 patients never required endoscopic or surgical intervention. Multivariate logistic regression analysis revealed that not consuming an elemental diet (OR 3.18, 95% CI 1.48-6.82; p < .01) and ileocecal valve (ICV) stenosis (OR 0.30, 95% CI 0.11-0.83; p = .02) were independently associated with not requiring EBD. The cumulative emergency hospitalisation-free rate also tended to be higher in patients not consuming an elemental diet or with ICV stenosis.

CONCLUSIONS

Two factors, namely not consuming an elemental diet and ICV stenosis, predict a long-term intervention-free prognosis in CD patients with small bowel stenosis.Key messagesWhen an endoscopically impassable small bowel stenosis is found in a CD patient, long-term follow-up without endoscopic intervention may be possible if the patient is asymptomatic, is not using an elemental diet, and the stenosis is ICV.

Systematic review with meta-analysis: The prevalence, risk factors and outcomes of upper gastrointestinal tract Crohn's disease

AIMS

Upper gastrointestinal Crohn's disease (UGI-CD) is an important subclassification of Crohn's Disease (CD). We performed a systematic review and meta-analysis to evaluate the prevalence, risk factors, and clinical outcomes associated with UGI-CD.

METHODS

We searched Embase and Medline for articles reporting the clinical information of UGI-CD in CD patients, through 27 October 2020. Disease location and phenotype were coded according to the Montreal classification, and results were pooled with random effects by DerSimonian and Laird model.

RESULTS

26 articles were included. The prevalence of UGI-CD was 13%. UGI-CD was most commonly found in the stomach (56%) and was associated with concurrent ileocolonic involvement (54%). Non-stricturing, non-penetrating UGI-CD was the most common behavioral phenotype (61%). L4-jejunal disease was associated with the highest rates of surgery. Region of origin did not significantly influence the location and phenotype of UGI-CD. Young, male patients presenting with erythema nodosum, aphthous ulcers and stricturing-phenotype are more likely to have UGI-CD, which in turn is linked to increased risk of hospitalization and surgery.

CONCLUSION

UGI-CD is present in 13% of patients with CD, and patients with L4-jejunal disease are more likely to require surgery. Further studies examining the effect of ethnicity and region on UGI-CD are needed.

Sarcopenia hinders the decline in disease activity after surgery for people with Crohn's disease: Preliminary results

OBJECTIVES

Surgical treatment is an important option for inducing remission in Crohn's disease (CD); indeed, the longer the disease duration, the higher the cumulative surgical rate. Previous studies have shown that the pathogenesis of Crohn's disease is associated with sarcopenia, a condition of reduced skeletal muscle mass. Here, we investigated the effect of preoperative sarcopenia on postoperative disease activity.

METHODS

This retrospective study included 56 patients with CD with medical records who met our inclusion criteria. Sarcopenia was diagnosed based on the psoas muscle mass index derived from computed tomography images, with predetermined cutoff values of <6.36 cm²/m² for men and <3.92 cm²/m² for women. We performed univariate and multivariate analyses to identify factors associated with sarcopenia.

RESULTS

Of the 56 participants, nine (16%) had sarcopenia. The rate of preoperative treatment with biological drugs was significantly lower in the sarcopenia group than the non-sarcopenia group. In addition, the operation time was significantly longer, and hemorrhage occurred more often, in the sarcopenia group than in the non-sarcopenia group. Postoperatively, the CD activity index at 6 mo had significantly decreased in the non-sarcopenia group (P = 0.01) but not in the sarcopenia group (P = 0.20). Univariate and multivariate analyses showed that a low total serum protein level was significantly associated with sarcopenia.

CONCLUSION

Our results suggest that to maximize the effect of surgical treatment for CD, an appropriate nutritional intervention should be performed before surgery, or surgery should be postponed until after the patient recovers from sarcopenia.

Diagnostic Features of Perianal Fistula in Patients With Crohn's Disease: Analysis of a Japanese Claims Database

Background

Perianal fistula (PAF) is a disabling complication of Crohn's disease (CD) which greatly impacts the quality of life. To address a scarcity of data in Asian populations, we determined the prevalence of CD-associated PAF in Japan, the order of diagnosis, and medical history of patients.

Methods

A retrospective, longitudinal, observational cohort study was conducted, using an employer-based health insurance claims database. The study included patients diagnosed with CD and/or PAF from October 2013 to September 2019.

Results

The age- and gender-adjusted prevalence rates of CD-associated PAF increased from 10.33 per 100 000 in 2014, to 13.68 per 100 000 in 2019. Among patients with CD-associated PAF, 15.7% were diagnosed with PAF after diagnosis of CD, 68.6% were diagnosed with PAF before diagnosis with CD, and 15.7% were diagnosed with CD and PAF within the same month. Of the patients diagnosed with CD after PAF, approximately 30% were diagnosed with PAF by the age of 20 years, whereas less than 10% of PAF patients without CD were diagnosed with PAF by the age of 20 years.

Conclusions

The study reveals the prevalence of CD-associated PAF in Japan and that most individuals were diagnosed with CD after the diagnosis of PAF. Crohn's disease may be underdiagnosed in patients with PAF; patients diagnosed with PAF at a young age should be monitored to allow timely diagnosis of CD.

Temporal trend of disease recognition, treatment paradigm, and clinical outcomes of Crohn disease in Thailand from 2000 through 2017: Is early use of thiopurines beneficial?

The prevalence of Crohn disease (CD) is increasing in Asia, but data from Southeast Asian population are scarce.The databases of 2 university-based national tertiary referral centers located in Bangkok, Thailand, were retrospectively reviewed for adult patients diagnosed with CD during January 2000 to December 2017. Disease characteristics, diagnosis, treatment, and outcomes were described and compared between the 2000 to 2009 cohort (cohort A) and the 2010 to 2017 cohort (cohort B).One hundred eighty-two patients (mean age: 46.4 years, 50% male) with 993 patient-years of follow-up were included. Thirteen percent had a history of intestinal resection, but were not diagnosed until disease recurrence. Another 6% were diagnosed at the time of first surgery. There was no improvement in diagnostic proficiency between cohorts. Mesalamine, corticosteroids, thiopurines, and biologics were prescribed in 75.8%, 81.3%, 84.6%, and 13.7% of patients, respectively (P > .05 between cohorts). Notably, thiopurines were started earlier in cohort B. Median time to the start of thiopurines was 6.2 and 1.65 months in cohort A and B, respectively (P < .01). However, the cumulative 5-year rates of disease behavior progression (P = .43), hospitalization (P = .14), and bowel surgery (P = .29) were not significantly different between cohorts. Subgroup analysis including only patients who required thiopurines showed the early use of thiopurines to be associated with lower risk of intestinal surgery after diagnosis (hazard ratio: 0.30, 95% confidence interval: 0.11-0.85).Early disease recognition and early introduction of immunomodulators may prevent long-term complications and reduce unnecessary surgery in CD.

A nationwide, multi-center, retrospective study of symptomatic small bowel stricture in patients with Crohn's disease

BACKGROUND

Small bowel stricture is one of the most common complications in patients with Crohn's disease (CD). Endoscopic balloon dilatation (EBD) is a minimally invasive treatment intended to avoid surgery; however, whether EBD prevents subsequent surgery remains unclear. We aimed to reveal the factors contributing to surgery in patients with small bowel stricture and the factors associated with subsequent surgery after initial EBD.

METHODS

Data were retrospectively collected from surgically untreated CD patients who developed symptomatic small bowel stricture after 2008 when the use of balloon-assisted enteroscopy and maintenance therapy with anti-tumor necrosis factor (TNF) became available.

RESULTS

A total of 305 cases from 32 tertiary referral centers were enrolled. Cumulative surgery-free survival was 74.0% at 1 year, 54.4% at 5 years, and 44.3% at 10 years. The factors associated with avoiding surgery were non-stricturing, non-penetrating disease at onset, mild severity of symptoms, successful EBD, stricture length < 2 cm, and immunomodulator or anti-TNF added after onset of obstructive symptoms. In 95 cases with successful initial EBD, longer EBD interval was associated with lower risk of surgery. Receiver operating characteristic analysis revealed that an EBD interval of ≤ 446 days predicted subsequent surgery, and the proportion of smokers was significantly high in patients who required frequent dilatation.

CONCLUSIONS

In CD patients with symptomatic small bowel stricture, addition of immunomodulator or anti-TNF and smoking cessation may improve the outcome of symptomatic small bowel stricture, by avoiding frequent EBD and subsequent surgery after initial EBD.

Gastrocolic fistula in Crohn’s disease detected by oral agent contrast-enhanced ultrasound: A case report of a novel ultrasound modality

BACKGROUND

Fistulas are common complications of Crohn’s disease (CD). Gastrocolic fistulas (GFs) are rare, occult and potentially life-threatening complications. Few cases of GFs have been reported. Oral agent contrast-enhanced ultrasound (OA-CEUS) is a novel technique of ultrasound (US) for gut. Contrast agent made by Chinese yam is taken orally to dilate the lumen of the upper gastrointestinal tract. Thus, the impediment of gas inside gastrointestinal tract is removed and a good acoustic window is provided for gastroin-testinal tract scanning. This paper describes a case of GF secondary to CD detected by OA-CEUS when it was missed by endoscopy and computed tomography (CT). To our knowledge, this is the first report of GF secondary to CD detected by OA-CEUS up to date.

CASE SUMMARY

A 29-year-old woman with a 6-year history of CD was admitted to our hospital for abdominal pain and diarrhea for 5 months without obvious predisposing causes. Initial gastroscopy failed to show any evidence of lesions. Colonoscopy revealed multiple erosions, mucosal nodularity, linear ulcers and a cobblestone appearance. A CT scan of her abdomen showed a complex multilocular structure adherent to the greater curvature of the stomach in her left lower abdomen, with fluid, gas and significant surrounding inflammation. CT also demonstrated an abdominal abscess, which was later treated with US-guided drainage. Colonoscopy, gastroscopy and CT missed the presence of a GF. OA-CEUS was performed. A contrast agent made from Chinese yam was taken orally to dilate the lumen of the gastrointestinal tract. A good acoustic window was provided for gastrointestinal tract scanning and the impediment of gas inside the gastrointestinal tract was removed. With the aid of the “window”, a canal with hypoechoic wall was identified connecting the greater curvature of stomach to the splenic colon flexure in free sections. We also observed the hyperechoic gas flowing dynamically inside the canal. Thus, a GF was suspected. US is the first imaging modality taking GF into account. At the same time, OA-CEUS identified the site of the fistula and its two orifices. Gastroscopy was performed again, revealing a small ulcer approximately 5 mm in diameter, which was considered as an orifice. On the basis of OA-CEUS and other examinations, the patient was diagnosed with a GF secondary to CD. Then, laparoscopic exploration, partial stomach resection, transverse colostomy and abdominal abscess drainage were performed. The patient recovered uneventfully.

CONCLUSION

GFs are rare, occult and potentially life-threatening complications in CD. US is one of the first-line modalities to evaluate CD and its complications. OA-CEUS, a novel technique of US for gut, may be helpful in reducing the possibility of a missed diagnosis of GF.

Enterocutaneous Fistula: A Simplified Clinical Approach

A “fistula” is an abnormal connection between two epithelial surfaces. Fistulae are named based on the two surfaces or lumens they connect to. Fistulae form due to loss of wall integrity from an underlying insult, leading to the penetrance of an adjacent organ or epithelized surface. Common causes of small bowel fistulae include sequelae of surgical intervention, foreign body, bowel diverticula, Crohn's disease, malignancy, radiation, and infection. A histopathological analysis displays acute and/or chronic inflammation due to the underlying pathology.

A thorough history and physical examination are important components of patient evaluation. Generally, patients will present with non-specific constitutional symptoms in addition to local symptoms attributed to the fistula. In rare instances, symptoms may be severe and life-threatening. Initial laboratory workup includes complete blood count, comprehensive metabolic panel, and lactate level. Radiologic imaging is useful for definitive diagnosis and helps delineate anatomy. In practice, computed tomography (CT) is the initial imaging modality. The addition of intravenous or enteric contrast may be helpful in certain situations. Magnetic resonance imaging (MRI) may also be used in special circumstances. Invasive procedures, such as endoscopy, can assist in the evaluation of mucosal surfaces to diagnose pathology such as inflammatory processes.

Appropriate management should include optimizing nutritional status, delineating fistulous tract anatomy, skincare, and managing the underlying disease. A non-operative approach is generally accepted as the initial approach especially in the acute/subacute setting. However, operative intervention is indicated in the setting of failed non-operative management. Successful management of small bowel fistulae requires a multidisciplinary team approach.

To conclude, a small bowel fistula is a complex clinical disease, with surgical intervention being the most common cause in developed countries. The non-operative approach should be trialed before an operative approach is considered.

Rate of Reoperation Decreased Significantly After Year 2002 in Patients With Crohn's Disease

BACKGROUND & AIMS

Patients with Crohn's disease (CD) can require multiple intestinal surgeries. We examined time trends and risk factors for reoperation in patients with CD who underwent intestinal surgery, focusing on the effects of postoperative medical treatments.

METHODS

We performed a retrospective analysis of 1871 patients with CD who underwent initial intestinal resection at 10 tertiary care institutions in Japan, with an initial surgical date after May 1982. We collected data on the background characteristics of all patients, including Montreal Classification, smoking status, and medical therapy after surgery (tumor necrosis factor antagonists [anti-TNF] agents or immunomodulators). The primary outcome was requirement for first reoperation. Rate of reoperation was estimated using the Kaplan-Meier method, and risk factors for reoperation were identified using the Cox regression model.

RESULTS

The overall cumulative 5- and 10-year reoperation rates were 23.4% and 48.0%, respectively. Multivariable analysis showed that patients who underwent the initial surgery after May 2002 had a significantly lower rate of reoperation than patients who underwent surgery before April 2002 (hazard ratio [HR], 0.72; 95% CI, 0.61-0.86). Preoperative smoking (HR, 1.40; 95% CI, 1.18-1.68), perianal disease (HR, 1.50; 95% CI, 1.27-1.77), and ileocolic type of CD (HR, 1.42; 95% CI, 1.20-1.69) were significant risk factors for reoperation. Postoperative use of immunomodulators (HR, 0.60; 95% CI, 0.44-0.81) and anti-TNF therapy (HR, 0.71; 95% CI, 0.57-0.88) significantly reduced the risk. Anti-TNF was effective in the bionaive subgroup.

CONCLUSIONS

The rate of reoperation in patients with CD significantly decreased after May 2002. Postoperative use of anti-TNF agents might reduce the reoperation rate for bionaive patients with CD.

Epidemiology and Clinical Outcomes of Inflammatory Bowel Disease: A Hospital-Based Study in Central Taiwan

The incidence and prevalence of inflammatory bowel disease (IBD) are low but increasing in Taiwan. We aimed to investigate the epidemiology and clinical outcomes of IBD in central Taiwan. We retrospectively analyzed patients with IBD diagnosed at our hospital between January 2000 and September 2018. The diagnostic criteria were based on endoscopic and pathologic findings. Clinical characteristics, treatment regimens, and treatment outcomes were analyzed. A total of 190 patients with IBD were enrolled (80 with Crohn's disease (CD) and 110 with ulcerative colitis (UC)). The mean age at diagnosis was 38.4 years (CD: 36 years, UC: 40 years). Male patients accounted for the majority of patients (71.1%). The male-to-female ratio was 3 : 1 for CD and 2.1 : 1 for UC. Current and ever smokers accounted for 30.5% of all patients. Only 4.2% of patients had a family history of IBD. Extraintestinal manifestations (EIMs) were reported in 7.9%, and colorectal cancers (CRCs) were reported in 2.1% of all patients. In patients with CD, the ileal type was the most common disease phenotype (57.5%), and the stricturing type was the most common disease behavior (60.0%). In patients with UC, left-sided colitis was the predominant disease extent (42.7%). The seroprevalence of hepatitis B virus (HBV) was 13.3%. The incidence of perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA) in patients with UC was 22%. 5-Aminosalicylic acids were the preferred treatment for UC, whereas corticosteroids, immunomodulators, and biologic agents were preferred for CD. In patients with CD, the bowel resection rate was 38.8%, and the incidence of hip avascular necrosis was 3.8%. In Taiwan, patients with IBD showed a male predominance, lack of familial clustering, a higher prevalence of HBV infection, and a lower prevalence of p-ANCA, EIMs, and CRC. Moreover, a higher incidence of the ileal type with poor outcomes of CD and left-sided predominance in UC were found.

Crohn's disease-specific mortality: a 30-year cohort study at a tertiary referral center in Japan

BACKGROUND

In this study, survival and cause of death were investigated in patients with Crohn's disease (CD) at a tertiary referral center.

METHODS

A database was created based on the medical records of 1108 CD patients who had a history of visiting our hospital to investigate background characteristics, cumulative survival rates from diagnosis, causes of death, and the standardized mortality ratio (SMR) for each cause of death. A follow-up questionnaire survey of patients followed up inadequately was also conducted. The cumulative survival rate from diagnosis was determined using the life table method and compared with that of a sex- and age-matched population model from the year 2000.

RESULTS

The study included 1108 patients whose mean age at diagnosis was 25.6 ± 10.8 years. The mean duration of follow-up was 14.6 ± 9.4 years, and there were 52 deaths. The cumulative survival rate was significantly lower 25 years after the diagnosis of CD (91.7%) than in the standard population model (95.7%). SMRs for both all causes [3.5; 95% confidence interval (CI): 2.7-4.6] and CD-specific causes (36.7; 95% CI 26.1-51.6) were high. Among the CD-specific causes, SMRs were especially high for small intestine and colorectal cancers, gastrointestinal diseases including intestinal failure (IF), perioperative complications, and amyloidosis.

CONCLUSION

The SMRs for both all causes and CD-specific causes were high in CD patients. CD-specific causes including intestinal cancer, IF, perioperative complications, and amyloidosis showed especially high SMRs.

Effect of a concomitant elemental diet with maintenance anti-tumor necrosis factor-α antibody therapy in patients with Crohn's disease: A multicenter, prospective cohort study

BACKGROUND AND AIM

The aim of this study was to clarify the additional effect of a concomitant elemental diet (ED) for patients with Crohn's disease on maintenance anti-tumor necrosis factor-α antibody (anti-TNF).

METHODS

Crohn's disease patients who received anti-TNF induction therapy were enrolled. Patients who achieved clinical response (defined as delta Crohn's disease activity index [CDAI] > 70 and CDAI < 200) at 10-14 weeks after the start of infliximab or adalimumab were included. Eligible patients took a tolerability test of ED (900 kcal/day) for 3 days. Then, patients who preferred concomitant ED and whose ED tolerance was confirmed were allocated to the ED group and given Elental 900 kcal/day or more. Other patients were allocated to the non-ED group. The primary endpoint was the cumulative remission rate at 2 years after baseline. Clinical relapse was defined as CDAI > 200 and/or need for additional treatment. Adherence to the ED was confirmed at each visit.

RESULTS

Seventy-two patients were included. Thirty-seven were allocated to the ED group, and 35 were allocated to the non-ED group. The cumulative remission rate at 2 years was not significantly different between the two groups (60.9% vs 56.7%, P = 0.98). Adherence to the ED in the ED group was relatively low, and only 11 patients were maintained on an ED of 900 kcal/day.

CONCLUSIONS

The addition of ED for Crohn's disease patients who responded to initial anti-TNF induction therapy was not found to improve outcomes. The efficacy of concomitant ED in other clinical settings, such as loss of response, needs to be clarified in the future (UMIN000009789).

Long-term prognosis of Japanese patients with biologic-naïve Crohn's disease treated with anti-tumor necrosis factor-α antibodies

Background/Aims

Few reports have described the long-term treatment outcomes of the anti-tumor necrosis factor-α antibody for Japanese Crohn’s disease (CD) patients. The aim of this study was to evaluate them and clarify the clinical factors that affect the long-term prognosis of the anti-tumor necrosis factor-α treatments.

Methods

This was a retrospective, observational, single-center cohort study. Japanese CD patients treated with either infliximab or adalimumab as a first-line therapy were analyzed. The cumulative retention rates of the biologics, relapse-free survival, and surgery-free survival were analyzed using Kaplan-Meier methods. The clinical factors associated with the long-term outcomes were estimated by both the log-rank test and Cox proportional hazard model.

Results

The cumulative retention rate was significantly higher in the group with a concomitant elemental diet of ≥900 kcal/day, baseline C-reactive protein (CRP) levels <2.6 mg/dL, and baseline serum albumin levels ≥3.5 g/dL, respectively. The baseline serum albumin levels were also associated with both relapse-free and surgery-free survival. The lack of concomitant use of an elemental diet ≥900 kcal/day was identified as the only independent risk factor for the withdrawal of the biologics.

Conclusions

Baseline CRP levels and serum albumin levels could affect the long-term outcomes in CD patients. Concomitant elemental diet of ≥900 kcal/day could have a positive influence on clinical treatment course.

Smoking and Inflammatory Bowel Disease: A Comparison of China, India, and the USA

BACKGROUND

Cigarette smoking is thought to increase the risk of Crohn's disease (CD) and exacerbate the disease course, with opposite roles in ulcerative colitis (UC). However, these findings are from Western populations, and the association between smoking and inflammatory bowel disease (IBD) has not been well studied in Asia.

AIMS

We aimed to compare the prevalence of smoking at diagnosis between IBD cases and controls recruited in China, India, and the USA, and to investigate the impact of smoking on disease outcomes.

METHODS

We recruited IBD cases and controls between 2014 and 2018. All participants completed a questionnaire about demographic characteristics, environmental risk factors and IBD history.

RESULTS

We recruited 337 participants from China, 194 from India, and 645 from the USA. In China, CD cases were less likely than controls to be current smokers (adjusted odds ratio [95% CI] 0.4 [0.2-0.9]). There was no association between current or former smoking and CD in the USA. In China and the USA, UC cases were more likely to be former smokers than controls (China 14.6 [3.3-64.8]; USA 1.8 [1.0-3.3]). In India, both CD and UC had similar current smoking status to controls at diagnosis. Current smoking at diagnosis was significantly associated with greater use of immunosuppressants (4.4 [1.1-18.1]) in CD cases in China.

CONCLUSIONS

We found heterogeneity in the associations of smoking and IBD risk and outcomes between China, India, and the USA. Further study with more adequate sample size and more uniform definition of smoking status is warranted.

The operative risk and natural history after the diagnosis of ileal penetrating Crohn's disease

BACKGROUND AND PURPOSE

Crohn's disease (CD) is marked by transmural inflammation of the bowel wall leading to stricturing and/or penetrating complications in the majority of patients. The natural history and operative risk after the diagnosis of an ileal penetrating complication is understudied. The aim was to study the disease course and need for surgery in patients diagnosed with a penetrating ileal CD complication and to assess the risk factors associated with worse postoperative outcome.

PATIENTS AND METHODS

In this cohort study, all cross-sectional imaging exams (computed tomography and/or magnetic resonance imaging) performed between 2006 and 2014 in patients with CD in a tertiary referral centre were reviewed for the presence of ileal penetrating complications (defined as abscesses, phlegmones and/or fistula). Demographic, clinical, biochemical, radiological and endoscopic factors were assessed retrospectively in these patients as well as the need for surgery (intestinal resection and/or strictureplasties) and postoperative complications.

RESULTS

In total, 1803 cross-sectional imaging exams in 957 CD patients were performed during the study period. In 113 patients, penetrating ileal CD complications were identified. The majority of these patients were referred for surgery (86%) (median time to surgery 1 month, interquartile range: 1-4.9 months). In multivariate analysis, only the presence of abscesses was associated with subsequent surgery (P=0.034; hazard ratio=1.65; 95% confidence interval: 1.04-2.61). Severe postoperative complications (Dindo-Clavien>II) were present in 13% of the patients. Albumin less than 32 g/l was associated with a five-fold increase in severe complications (P=0.039; hazard ratio=4.9; 95% confidence interval: 1-22). Up to 35% of the patients needed no further medical treatment during the first 5 years postoperatively.

CONCLUSION

In this cohort, the majority of patients with penetrating ileal CD underwent surgery. The presence of an abscess showed a significant association with the need for surgery. There was an acceptable postoperative complication rate. Patients with low albumin had an unfavourable postoperative course. The long-term outcome after surgery was favourable.

Predicting outcomes to optimize disease management in inflammatory bowel disease in Japan: their differences and similarities to Western countries

Inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), is a chronic inflammatory disease of the gastrointestinal tract, with increasing prevalence worldwide. IBD Ahead is an international educational program that aims to explore questions commonly raised by clinicians about various areas of IBD care and to consolidate available published evidence and expert opinion into a consensus for the optimization of IBD management. Given differences in the epidemiology, clinical and genetic characteristics, management, and prognosis of IBD between patients in Japan and the rest of the world, this statement was formulated as the result of literature reviews and discussions among Japanese experts as part of the IBD Ahead program to consolidate statements of factors for disease prognosis in IBD. Evidence levels were assigned to summary statements in the following categories: disease progression in CD and UC; surgery, hospitalization, intestinal failure, and permanent stoma in CD; acute severe UC; colectomy in UC; and colorectal carcinoma and dysplasia in IBD. The goal is that this statement can aid in the optimization of the treatment strategy for Japanese patients with IBD and help identify high-risk patients that require early intervention, to provide a better long-term prognosis in these patients.

Efficacy of Endoscopic Balloon Dilation for Small Bowel Strictures in Patients With Crohn's Disease: A Nationwide, Multi-centre, Open-label, Prospective Cohort Study

BACKGROUND AND AIMS

Endoscopic balloon dilation [EBD] is an alternative to surgery for Crohn's strictures. However, there have been no prospective studies of EBD for small bowel strictures in patients with Crohn's disease [CD]. The aim of this study was to clarify the efficacy and safety of EBD using balloon-assisted enteroscopy for small bowel strictures in CD.

METHODS

This was a nationwide, multi-centre, open-label, prospective cohort study. The subjects were CD patients with at least one symptom [abdominal pain, abdominal bloating, nausea] attributable to small bowel stricture. The primary endpoint related to short-term outcomes was the level of improvement of symptoms evaluated using a 10-cm visual analogue scale [VAS]. Cases in which VAS scores for all symptoms improved 4 weeks after EBD compared with baseline were considered to have short-term symptomatic improvement. Factors related to short-term treatment outcomes and safety were investigated as secondary endpoints.

RESULTS

A total of 112 patients were enrolled. Seventeen were later excluded because they did not meet the criteria, and the analysis was conducted with the remaining 95 patients. Of these 95 patients, procedure failure occurred in six [6.3%], and short-term symptomatic improvement was achieved in 66 patients [69.5%]. Adverse events were seen in five patients [5%] and all of these improved with conservative treatment. A large dilation diameter of the balloon was a factor contributing to the success of EBD.

CONCLUSIONS

EBD using balloon-assisted enteroscopy for small bowel strictures in CD patients was shown to be an effective and safe procedure.

CLINICAL TRIAL REGISTRY

UMIN000005946.

Different clinical outcomes in Crohn's disease patients with esophagogastroduodenal, jejunal, and proximal ileal disease involvement: is L4 truly a single phenotype?

BACKGROUND

The Montreal classification defines L4 Crohn's disease (CD) as any disease location proximal to the terminal ileum, which anatomically includes L4-esophagogastroduodenal (EGD), L4-jejunal, and L4-proximal ileal involvement. L4-jejunal disease was established to be associated with poor prognosis. However, the outcome of patients with L4-proximal ileal disease or L4-EGD remains to be clarified. Our study aimed to investigate whether the outcome differs among CD patients with L4-EGD, L4-jejunal, and L4-proximal ileal disease.

METHODS

In our retrospective cohort study, 483 patients with confirmed CD were included. The primary outcome was intestinal surgery. Demographic features and outcomes were compared among L4-EGD, L4-jejunal, and L4-proximal ileal disease.

RESULTS

Thirty-nine (8.1%) patients had isolated L4 disease, whereas 146 patients had L4 as well as concomitant L1, L2, or L3 disease. During a median follow up of 5.8 years, L4 patients were more likely to have intestinal surgeries compared to non-L4 patients (31% versus 16%, p < 0.001). The percentage of L4-jejunal patients who underwent surgery was higher than that of L4-proximal ileal (66% versus 28%, p < 0.001), and both of these subtypes of L4 were at higher risk for intestinal resection compared to L4-EGD patients (66% and 28% versus 9%, respectively, p < 0.001 and p < 0.05). On multi-variable analysis, L4-jejunal (HR 3.08; 95% CI 1.30-7.31) and L4-proximal ileal disease (HR 1.83; 95% CI 1.07-3.15) were independent predictors for intestinal resection.

CONCLUSIONS

L4 disease had worse prognosis compared to non-L4 disease. Within L4 disease, phenotype of L4-jejunal and L4-proximal ileal disease indicated higher risk for intestinal surgery. It might be justified to further characterize the L4 phenotype of the Montreal classification into three specific subgroups including L4-EGD, L4-jejunal, and L4-proximal ileal disease, similar to the Paris classification of pediatric patients.

Underestimation of Smoking Rates in an East Asian Population with Crohn's Disease

Background/Aims

The reported rates of current smoking at the time of Crohn’s disease (CD) diagnosis tend to be low in East Asian studies. However, we hypothesized that East Asian patients may be reluctant to disclose their smoking history, likely because of the influence of the Confucian culture.

Methods

We prospectively re-evaluated the smoking status at diagnosis in 1,437 Korean CD patients whose smoking status had been reported in our previous study.

Results

After re-evaluation, the current smokers at diagnosis increased from 388 patients (27.0%) to 445 patients (31.0%), indicating that 12.8% (57 of 445 patients) of the current smokers at diagnosis did not disclose their smoking status at their initial evaluation. The proportion of current smokers at diagnosis who had initially concealed their smoking status was significantly higher among the female patients (29.7%, 11/37) compared with the male patients (11.3%, 46/408) (p<0.005) and among the patients who were ≤18 years old at diagnosis (56.4%, 22/39) compared with the patients >18 years old at diagnosis (8.6%, 35/406) (p<0.001).

Conclusions

Subgroups of Korean CD patients, particularly young patients and female patients, are reluctant to disclose their smoking history. Therefore, the suggestion that smoking is not a risk factor for the development of CD in East Asians should be made with caution.

Current status of endoscopic balloon dilation for Crohn's disease

The therapeutic target in Crohn's disease (CD) has been raised to the achievement of mucosal healing. Although effective treatments that target cytokines and other molecules has been widely used for CD, intestinal strictures are still a major cause of surgery. Endoscopic balloon dilation (EBD) is known to be an effective and safe intervention for intestinal strictures in CD. Since frequent intestinal resection often results in short bowel syndrome and can decrease the quality of life, EBD can help avoid surgery. EBD with a conventional colonoscope for Crohn's strictures of the colon and ileo-colonic anastomosis has established efficacy and safety. In addition, EBD using balloon-assisted enteroscopy has recently been applied for small bowel Crohn's strictures. Although the evidence is not strong, EBD may become an alternative to surgery in small bowel strictures in CD. EBD and other new methods such as self-expanding stent implantation for Crohn's strictures may be useful and safe; however, it is important to address several issues regarding these interventions and to establish a protocol for combined therapies.

Risk Factors for the Development of Fistulae and Stenoses in Crohn Disease Patients in the Swiss Inflammatory Bowel Disease Cohort

Background

Fistulae and stenoses represent frequent and severe complications in patients with Crohn disease (CD). Our study aimed to identify risk factors for fistula and stenosis formation in CD patients.

Summary

We retrieved data of 1,600 CD patients from the nationwide Swiss Inflammatory Bowel Disease Cohort Study (SIBDCS). The risk for fistulae and stenoses in relation to gender, age at diagnosis, smoking status at diagnosis, and ileal involvement at diagnosis were analyzed. In the multivariate analysis, female gender showed a lower risk for developing perianal and any fistula (risk ratio [RR] 0.721, 95% confidence interval [CI] 0.582-0.893, p = 0.003 and RR 0.717, 95% CI 0.580-0.888, p = 0.002, respectively), and older age at diagnosis showed a lower risk for developing perianal fistula (RR 0.661, 95% CI 0.439-0.995, p = 0.047). Furthermore, ileal involvement was associated with a lower risk for perianal fistula (RR 0.713, 95% CI 0.561-0.906, p = 0.006), a lower risk for any fistula (RR 0.709, 95% CI 0.558-0.901, p = 0.005), and a higher risk for stenosis (RR 2.170, 95% CI 1.728-2.725, p < 0.001).

Key Messages

In the nationwide SIBDCS, younger age at diagnosis and male gender were risk factors for developing perianal and nonperianal fistulae. Additionally, ileal involvement was revealed to be a potent risk factor (RR 2.170) for developing a stenosis.

Inflammatory bowel disease on the risk of acute pancreatitis: A population-based cohort study

BACKGROUND AND AIMS

To determine whether inflammatory bowel disease (IBD) influences the risk of acute pancreatitis.

METHODS

We identified 11,909 patients diagnosed with IBD between 2000 and 2010 from Taiwan National Health Insurance Research Database as the study cohort. A comparison cohort comprised 47,636 age-matched patients without IBD. Both cohorts were followed-up until the end of 2010 or until being censored. Cox proportional hazards regression models were used to study the effects of IBD on the risks of acute pancreatitis.

RESULTS

The overall incidence of acute pancreatitis was 3.56-fold higher in the study cohort than in the comparison cohort (31.8 vs 8.91 per 10,000 person-years, crude hazard ratio [HR] = 3.56, 95% confidence interval [CI] = 2.96-4.28). After adjustment for age, sex, and comorbidities, namely alcohol-related disease, biliary stone, hypertension, hyperlipidemia, diabetes mellitus, obesity, hepatitis B, hepatitis C, hypertriglyceridemia, cardiovascular diseases, chronic kidney disease, chronic obstructive pulmonary disease, and hypercalcemia, the adjusted HR for acute pancreatitis was 2.93-fold higher (95% CI = 2.40-3.58) in the study cohort than in the comparison cohort.

CONCLUSIONS

IBD is a risk factor for acute pancreatitis.