Update on the Natural Course of Fistulizing Perianal Crohn's Disease in a Population-Based Cohort

Rectovaginal Fistula in Crohn's Disease: When and How to Operate?

Rectovaginal fistula (RVF) occurring during the course of Crohn's disease (CD) constitutes a therapeutic challenge and is characterized by a high rate of recurrence. To optimize the outcome of CD-related RVF repair, the best conditions for correct healing should be obtained. Remission of CD should be achieved with no active proctitis, the perianal CD activity should be minimized, and local septic complications should be controlled. The objective of surgical repair is to close the fistula tract with minimal recurrence and functional disturbance. Several therapeutic strategies exist and the approach should be tailored to the anatomy of the RVF and the quality of the local supporting tissues. Herein, we review the medical and surgical management of CD-related RVF.

The Essential Role of a Multidisciplinary Approach in Inflammatory Bowel Diseases: Combined Medical-Surgical Treatment in Complex Perianal Fistulas in CD

Perianal fistulizing Crohn's disease (PFCD) represents a challenging and complex disease phenotype. Patients typically suffer a more severe disease course than those without perianal complications and are often managing debilitating symptoms. Etiology is understood to be multifactorial, with genetic predisposition, microbiological insult, aberrant immunity, and mechanical factors all implicated. As a result, multimodal treatment strategies must be employed to achieve disease control and fistula closure. This requires the complimentary involvement of medical and surgical disciplines in order to ensure thorough assessment and treatment tailored to the individual scenario and patient goals. The aim of this article is to describe an overview of the various treatment strategies available for PFCD, focusing on how a synergistic approach is required to ensure maximal chances of success.

Epidemiology and Natural History of Perianal Crohn's Disease: A Systematic Review and Meta-Analysis of Population-Based Cohorts

BACKGROUND AND AIMS

Perianal Crohn's disease (pCD) is a potentially severe phenotype of CD. We conducted a systematic review with meta-analysis to estimate cumulative incidence, risk factors, and outcomes of pCD in population-based cohort studies.

METHODS

Through a systematic literature review through March 1, 2021, we identified population-based inception cohort studies reporting cumulative incidence of perianal disease (primarily abscess and/or fistula) in patients with CD. We estimated the cumulative incidence of pCD at presentation and 1-, 5-, and 10-year follow-up, and risk factors for perianal disease and outcomes including risk of major (bowel resection, proctectomy, ostomy) and minor perianal (incision and drainage, seton placement, etc.) surgery.

RESULTS

In 12 population-based studies, prevalence of pCD was 18.7% (95% confidence interval [CI], 12.5%-27.0%) with 1-, 5-, and 10-year risk of perianal disease being 14.3% (95% CI, 7.9%-24.6%), 17.6% (95% CI, 11.3%-26.5%), and 18.9% (95% CI, 15.0%-23.4%), respectively. Approximately 11.5% of patients (95% CI, 6.7%-19.0%) had perianal disease at or before CD diagnosis. Colonic disease location and rectal involvement were associated with higher risk of pCD. Overall, 63.3% of patients (95% CI, 53.3-72.3) required minor perianal surgery and 6.4% of patients (95% CI, 1.8%-20.6%) required major abdominal surgery for pCD. Use of biologic therapy for pCD is common and has steadily increased throughout the years.

CONCLUSIONS

Approximately 1 in 5 patients with CD develops perianal disease within 10 years of CD diagnosis, including 11.5% who have perianal disease at presentation. Approximately two-thirds of patients require perianal surgery, with a smaller fraction requiring major abdominal surgery.

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.

Perianal and Luminal Relapse Following Perianal Surgical Intervention in Crohn's Disease

Background and Aims

Fistula relapse occurs in 20–30% of patients with perianal Crohn’s disease (PCD) despite optimal medico-surgical management. We aimed in this study to assess the rate of perianal and luminal relapse after surgically induced remission and to determine factors associated with fistula relapse.

Methods

Consecutive perianal CD patients who achieved clinical remission after surgery for fistulising PCD from January 2013 to January 2019 were included. The cumulative probabilities of relapse-free survival were estimated using the Kaplan–Meier method.

Results

A total of 130 patients were included. Sixty-six of 130 patients received infliximab (IFX) therapy after perianal surgery. After a median follow-up of 62 months (interquartile range [IQR]: 28–117 months), perianal relapse occurred in 30 of 64 (46.9%) nonbiological medication-treated cases and in 14 of 66 (21.1%) cases in the IFX therapy group. The cumulative probabilities of perianal relapse-free survival in patients with nonbiological treatment were 77.1% at 1 year, 54.6% at 3 years, and 30% at 5 years. The rates of survival without perianal fistula relapse in the IFX-treated group were 91.6%, 69.2%, and 59.3% at 1, 3 and 5 years, respectively. In patients treated with IFX after perianal surgery, discontinuation of IFX therapy (odds ratio [OR]=2.43, p=0.036), a penetrating CD phenotype (OR=4.324, p=0.019), and a complex perianal fistula (OR=3.392, p=0.026) were independently associated with perianal relapse in multivariate analysis.

Conclusion

Infliximab therapy reduced the risk of perianal relapse after surgical remission in PCD patients compared with nonbiological treatment. However, approximately 40% of patients using infliximab experienced perianal relapse at 5 years, and patients who discontinued use of IFX or experienced a penetrating phenotype or a complex perianal fistula were associated with increased relapse rate.

Ability of Pelvic Magnetic Resonance Imaging to Predict Clinical Course of Perianal Fistula in Paediatric Crohn's Disease Patients

BACKGROUND AND AIMS

Evidence is limited regarding clinical course and magnetic resonance imaging [MRI] features of perianal fistula [PAF] in Korean children with Crohn's disease [CD]. We investigated MRI features of PAF and associations with long-term outcomes.

METHODS

We retrospectively analysed 243 patients with pelvic MRI for diagnosis of CD. Incidence of clinically evident PAF at diagnosis was determined, as were the proportions of patients with clinical failure [failure to achieve fistula healing within 1 year] and recurrence [new/recurrent PAF after fistula healing within 1 year]. Associations between outcomes and MRI features, specified in modified Van Assche index and MAGNIFI-CD, were evaluated. Associations between later development of clinically evident PAF and subclinical PAF detected on MRI at diagnosis were evaluated.

RESULTS

Among 243 included patients, 108 [44.4%] and 76 [31.3%] had clinically evident and subclinical PAF at diagnosis, respectively; 66.4% of the patients with clinically evident PAF achieved fistula healing within 1 year, and 32.7% of those patients developed recurrence. Fistula length and dominant features of the tracts were associated with clinical failure, and fistula length was associated with recurrence. Clinically evident PAF developed in 17.0% of the patients without clinically evident PAF at diagnosis. We did not find statistically significant association between subclinical PAF and later development of clinically evident PAF [adjusted hazard ratio, 2.438; p = 0.15].

CONCLUSIONS

A considerable proportion of Korean paediatric CD patients had clinically evident and subclinical PAF. Fistula length and dominant feature of the tract on MRI are useful predictors of outcomes.

Prognostic biomarkers to identify patients likely to develop severe Crohn's disease: a systematic review

BACKGROUND

Identification of biomarkers that predict severe Crohn's disease is an urgent unmet research need, but existing research is piecemeal and haphazard.

OBJECTIVE

To identify biomarkers that are potentially able to predict the development of subsequent severe Crohn's disease.

DESIGN

This was a prognostic systematic review with meta-analysis reserved for those potential predictors with sufficient existing research (defined as five or more primary studies).

DATA SOURCES

PubMed and EMBASE searched from inception to 1 January 2016, updated to 1 January 2018.

REVIEW METHODS

Eligible studies were studies that compared biomarkers in patients who did or did not subsequently develop severe Crohn's disease. We excluded biomarkers that had insufficient research evidence. A clinician and two statisticians independently extracted data relating to predictors, severe disease definitions, event numbers and outcomes, including odds/hazard ratios. We assessed risk of bias. We searched for associations with subsequent severe disease rather than precise estimates of strength. A random-effects meta-analysis was performed separately for odds ratios.

RESULTS

In total, 29,950 abstracts yielded just 71 individual studies, reporting 56 non-overlapping cohorts. Five clinical biomarkers (Montreal behaviour, age, disease duration, disease location and smoking), two serological biomarkers (anti-Saccharomyces cerevisiae antibodies and anti-flagellin antibodies) and one genetic biomarker (nucleotide-binding oligomerisation domain-containing protein 2) displayed statistically significant prognostic potential. Overall, the strongest association with subsequent severe disease was identified for Montreal B2 and B3 categories (odds ratio 4.09 and 6.25, respectively).

LIMITATIONS

Definitions of severe disease varied widely, and some studies confounded diagnosis and prognosis. Risk of bias was rated as 'high' in 92% of studies overall. Some biomarkers that are used regularly in daily practice, for example C-reactive protein, were studied too infrequently for meta-analysis.

CONCLUSIONS

Research for individual biomarkers to predict severe Crohn's disease is scant, heterogeneous and at a high risk of bias. Despite a large amount of potential research, we encountered relatively few biomarkers with data sufficient for meta-analysis, identifying only eight biomarkers with potential predictive capability.

FUTURE WORK

We will use existing data sets to develop and then validate a predictive model based on the potential predictors identified by this systematic review. Contingent on the outcome of that research, a prospective external validation may prove clinically desirable.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016029363.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 45. See the NIHR Journals Library website for further project information.

Multidisciplinary management of perianal Crohn's disease

PURPOSE OF REVIEW

Multiple new medications with novel mechanisms of action are now available to treat Crohn's disease (CD). However, they have varying effectiveness in the management of perianal CD. Identifying the most appropriate therapy and optimizing it is essential to maximize effectiveness of therapy. Additionally, the management of perianal CD requires imaging of the perianal area to identify the fistula anatomy and local complications such as abscesses that require surgical drainage. Initial surgical assessment is key to drain abscesses and allow fistula healing with medical therapy.

RECENT FINDINGS

Although anti-tumor necrosis factor (TNFs) remain the most effective medications to treat perianal CD, real-world data suggests that ustekinumab may be a 2nd-line option in patients nonresponsive to an anti-TNF or having contraindications. Mesenchymal stem cells are an emerging therapeutic approach that is currently in Phase 3 trials in the United States and poised to play a major role in the treatment algorithm.

SUMMARY

The management of perianal CD requires a multidisciplinary approach with a combination of initial imaging and surgical assessment to adequately control local sepsis, optimization of biological therapy with adjunct antibiotics or immunomodulators, and close clinical follow-up with imaging to evaluate response to therapy and guide further surgical management options.

Healing of rectal advancement flaps for anal fistulas in patients with and without Crohn's disease: a retrospective cohort analysis

Background

Surgical closure of anal fistulas with rectal advancement flaps is an established standard method, but it has a high degree of healing failure in some cases. The aim of this study was to identify risk factors for anal fistula healing failure after advancement flap placement between patients with cryptoglandular fistulas and patients with Crohn’s disease (CD).

Methods

From January 2010 to October 2020, 155 rectal advancement flaps (CD patients = 55, non-CD patients = 100) were performed. Patients were entered into a prospective database, and healing rates were retrospectively analysed.

Results

The median follow-up period was 189 days (95% CI: 109–269). The overall complication rate was 5.8%. The total healing rate for all rectal advancement flaps was 56%. CD patients were younger (33 vs. 43 years, p < 0.001), more often female (76% vs. 30%, p < 0.001), were administered more immunosuppressant medication (65% vs. 5%, p < 0.001), and had more rectovaginal fistulas (29% vs. 8%, p = 0.001) and more protective stomas (49% vs. 2%, p < 0.001) than patients without CD. However, no difference in healing rate was noted between patients with or without CD (47% vs. 60%, p = 0.088).

Conclusions

Patients with anal fistulas with and without Crohn’s disease exhibit the same healing rate. Although patients with CD display different patient-specific characteristics, no independent factors for the occurrence of anal fistula healing failure could be determined.

Trial registration Not applicable due to the retrospective study design.

Clinical outcomes and long-term prognosis of perianal Crohn's disease in an Asian population

BACKGROUND AND AIM

The clinical impact of perianal Crohn's disease (CD) (pCD), a well-known poor prognostic factor of CD, has not been fully evaluated in Asian patients. We investigated the outcomes of CD in Korean patients according to the presence of pCD at CD diagnosis.

METHODS

Using 2010-2014 data from the national health insurance claims database, we evaluated the disease course of CD according to the presence of pCD at CD diagnosis. The results were verified in a hospital-based cohort of 2923 patients.

RESULTS

The cumulative risk of intestinal resection was lower in patients with pCD at diagnosis than in those without, in the population-based cohort (9.1% vs 14.7% at 5 years after diagnosis, P < 0.001), but it was similar between the two groups in the hospital-based cohort (36.8% vs 36.8% at 10 years after diagnosis, P = 0.950). Moreover, the cumulative risk of behavioral progression was not significantly different between the two groups in the hospital-based cohort (43.4% vs 41.6% at 10 years after diagnosis, P = 0.366). On multivariable analysis, pCD at CD diagnosis was not a predictor of intestinal resection, behavioral progression, CD-related hospital admission, or diverting surgery; however, it was an independent predictor of proctectomy (hazard ratio [HR] 3.210, P < 0.001) and anorectal cancer (HR 3.104, P = 0.047).

CONCLUSIONS

Although the presence of pCD increased the risk of proctectomy and anorectal cancer in Asian patients, the clinical impact of pCD on the overall outcomes of patients with CD may be less significant in Asian patients compared with Western patients.

Predictors of reoperation for perianal fistula in Crohn's disease

OBJECTIVE

Treating perianal fistula in cases of Crohn's disease (CD) remains challenging and the postoperative recurrence rate of perianal fistula is 22%-28%. This study aimed to identify the predictive risk factors for reoperation in Korean CD patients with perianal fistula.

METHODS

Medical records of the patients with clinically and pathologically confirmed CD who underwent surgical treatment for perianal fistulas at four referral centers in Korea between March 2010 and February 2020 were retrospectively reviewed. The rate of reoperation due to perianal fistula recurrence, which was defined as any subsequent surgery for perianal fistula or abscess, and the potential risk factors for reoperation were analyzed.

RESULTS

Fifty-one patients at a mean age of 22 years were included in the study. During a median follow-up period of 26 months (range 2-89 mo), 21 (41.2%) patients underwent reoperation because of recurrent perianal fistula or abscess. The median interval from the first surgery to reoperation was 13 months. A multivariate Cox regression analysis revealed that drug escalation (from 5-aminosalicylic acid [5-ASA] to thiopurine or from 5-ASA or thiopurine to anti-tumor necrosis factor agents) after the first surgery was associated with a reduced likelihood of reoperation (hazard ratio 0.316, 95% confidence interval 0.117-0.858, P = 0.024).

CONCLUSIONS

The postoperative recurrence rate was relatively high (41.2%) after the first surgery for perianal fistula in Korean patients with CD. Drug escalation therapy after the first surgery may help reduce the need for reoperation for perianal fistula.

Higher Postinduction Infliximab Concentrations Are Associated With Improved Clinical Outcomes in Fistulizing Crohn's Disease: An ACCENT-II Post Hoc Analysis

INTRODUCTION

There are only limited data regarding the role of therapeutic drug monitoring in fistulizing Crohn's disease (CD). We investigated the association between both induction and maintenance serum infliximab concentrations and favorable therapeutic outcomes in patients with fistulizing CD.

METHODS

This was a post hoc analysis of the ACCENT-II trial evaluating patients with fistulizing CD receiving induction (n = 282) and maintenance infliximab therapy (n = 139). Investigated therapeutic outcomes at both week 14 and week 54 included fistula response, complete fistula response, C-reactive protein (CRP) normalization (≤5 mg/L) in patients with an elevated baseline CRP, and a more stringent outcome of composite remission, defined as combined complete fistula response and CRP normalization. Associations between serum infliximab concentrations and outcomes were assessed by multivariable logistic regression models.

RESULTS

Higher week 14 infliximab concentrations were independently associated with week 14 fistula response (odds ratio [OR]: 1.16; 95% confidence interval [CI]: 1.02-1.32; P = 0.019), and composite remission (OR: 2.32; 95% CI: 1.55-3.49; P < 0.001). Higher week 14 infliximab concentrations were also independently associated with week 54 composite remission (OR: 2.05; 95% CI: 1.10-3.82; P = 0.023). Based on receiver operating characteristic curve analysis, week 14 infliximab concentrations thresholds with combined maximal sensitivity and specificity of ≥20.2 μg/mL at week 2, ≥15 μg/mL at week 6, and ≥7.2 μg/mL at week 14 were associated with week 14 composite remission.

DISCUSSION

Higher post-induction infliximab concentrations are associated with early and long-term favorable therapeutic outcomes in patients with fistulizing CD.

Effectiveness of Infliximab on Deep Radiological Remission in Chinese Patients with Perianal Fistulizing Crohn's Disease

BACKGROUND AND AIMS

Information concerning deep radiological healing of perianal fistulas in Chinese patients with CD is limited. The present study aimed to establish the effectiveness of infliximab on CD-related perianal fistulas using magnetic resonance imaging (MRI) and identify predictors of deep radiological remission of fistulas.

METHODS

We retrospectively reviewed patients with CD with draining perianal fistulas treated with infliximab and included only those who underwent clinical assessment and MRI before and after infliximab therapy.

RESULTS

Among 178 patients who underwent repeated MRI and clinical assessment, 65.2% had complex fistulas. Post-infliximab therapy, 55.1% of patients with perianal fistulizing CD showed clinical remission and 26.4% presented a clinical response; 38.2% had deep radiological remission, and 34.3% had a partial response based on the Ng score; the Van Assche scores decreased obviously compared with baseline. Prolonged infliximab infusion (18 times) presented higher radiological remission rates in patients with CD with complex fistulas. Concomitant treatment with azathioprine increased the fistula healing rate compared with infliximab alone (50% vs. 36.9%, P < 0.001). Younger age at diagnosis of CD, proctitis and requiring perianal surgery were identified as predictors of poor deep radiological remission of fistulas. Eight of ten patients who stopped infliximab and switched to an alternative agent retained a status of fistula healing in the first year of follow-up.

CONCLUSIONS

Infliximab induced deep radiological remission of perianal fistulas in Chinese patients with CD. Routine MRI should be used to monitor fistula healing. Patients with younger age at diagnosis of CD, proctitis, and/or requiring perianal surgery should receive combined therapy and careful monitoring.

Selecting End Points for Disease-Modification Trials in Inflammatory Bowel Disease: the SPIRIT Consensus From the IOIBD

BACKGROUND AND AIMS

Inflammatory bowel diseases (IBD), encompassing Crohn's disease (CD) and ulcerative colitis (UC), are chronic and disabling disorders. Prospective disease-modification trials to prevent disease progression are eagerly awaited. However, disease progression is not clearly defined. The objective of the Selecting End PoInts foR Disease-ModIfication Trials (SPIRIT) initiative was to achieve international expert consensus on the endpoints to be used in future IBD-disease modification trials.

METHODS

This initiative under the auspices of the International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) began with a systematic literature search to evaluate the current evidence on the definition of disease progression in IBD. On October 22, 2019, a consensus meeting took place during the United European Gastroenterology Week (UEGW) Congress in Barcelona, during which predefined proposed statements were discussed in a plenary session and voted on anonymously. Agreement was defined as at least 75% of participants voting for any one statement.

RESULTS

The group agreed that the ultimate therapeutic goal in both CD and UC is to prevent disease impact on patient's life (health-related quality of life, disability, fecal incontinence), midterm complications (encompass bowel damage in CD, IBD-related surgery and hospitalizations, disease extension in UC, extraintestinal manifestations, permanent stoma, short bowel syndrome), and long-term complications (gastrointestinal and extraintestinal dysplasia or cancer, mortality).

CONCLUSIONS

Recommendations on which goals to achieve in disease-modification trials for preventing disease progression in patients with IBD are proposed by the SPIRIT consensus. However, these recommendations will require validation in actual clinical studies before implementation in disease-modification trials.

Treatment Strategy for Perianal Fistulas in Crohn Disease Patients: The Surgeon's Point of View

Perianal fistula is a frequent complication and one of the subclassifications of Crohn disease (CD). It is the most commonly observed symptomatic condition by colorectal surgeons. Accurately classifying a perianal fistula is the initial step in its management in CD patients. Surgical management is selected based on the type of perianal fistula and the presence of rectal inflammation; it includes fistulotomy, fistulectomy, seton procedure, fistula plug insertion, video-assisted ablation of the fistulous tract, stem cell therapy, and proctectomy with stoma creation. Perianal fistulas are also managed medically, such as antibiotics, immunomodulators, and biologics including anti-tumor necrosis factor-alpha agents. The current standard treatment of choice for perianal fistula in CD patients is the multidisciplinary approach combining surgical and medical management; however, the rate of long-term remission is low and is reported to be 50% at most. Therefore, the optimum management strategy for perianal fistulas associated with CD remains controversial. Currently, the goal of management for CD-related perianal fistulas are controlling symptoms and maintaining long-term anal function without proctectomy, while monitoring progression to anorectal carcinoma. This review evaluates perianal fistula in CD patients and determines the optimal surgical management strategy based on recent evidence.

The Incidence and Disease Course of Perianal Crohn's Disease: A Danish Nationwide Cohort Study, 1997-2015

BACKGROUND AND AIMS

Perianal Crohn's disease [CD] places a considerable burden on patients' quality of life and is complex to treat. Despite its impact and high frequency, few studies have investigated the incidence and disease course of perianal CD. The aim of this study was to assess the incidence and disease course of perianal CD in adult patients throughout a 19-year period.

METHODS

The cohort comprised all individuals aged 18 years or older who were diagnosed with CD in Denmark between January 1, 1997, and December 31, 2015, according to the National Patient Registry [NPR].

RESULTS

A total of 1812 [19%] out of 9739 patients with CD were found to have perianal CD. Perianal fistulas were the most common manifestation, accounting for 943 [52%] cases. The incidence of perianal CD remained stable over time. Patients with perianal CD were found to have an increased risk of undergoing major abdominal surgery compared with patients without perianal CD (hazard ratio: 1.51, 95% confidence interval [CI]: 1.40 to 1.64, p <0.001) in a multivariate Cox regression analysis. The incidence rate ratios of anal and rectal cancer in perianal CD patients were 11.45 [95% CI: 4.70 to 27.91, p <0.001] and 2.29 [95% CI: 1.25 to 4.20, p = 0.006], respectively, as compared with non-IBD matched controls.

CONCLUSIONS

In this nationwide study, 19% of CD patients developed perianal disease. Patients with perianal CD were at increased risk of undergoing major surgery compared with non-perianal CD patients. The risk of anal and rectal cancer was increased in patients with perianal CD compared with non-IBD matched controls.

PODCAST

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Modern Management of Perianal Crohn's Disease: A Review

Perianal Crohn's disease (CD) is a complex manifestation of CD that affects approximately 10% of patients. The spectrum of disease is quite variable, ranging from relatively mild disease to severe, aggressive manifestations that result in frequent hospitalizations, multiple surgeries, and poor quality of life. Despite significant recent advances in surgical and medical management, treatment remains challenging and frequently requires a multidisciplinary medical-surgical approach. The goal of this article is to review the current literature regarding the work-up, treatment, and future directions of therapy. Crucial features of effective management include the precise identification of manifestations, control of sepsis, limiting rectal inflammation, frequently with use of antitumor necrosis factor agents, and avoidance of extensive surgery.

Predictors of Ustekinumab Failure in Crohn's Disease After Dose Intensification

BACKGROUND

Many patients with Crohn's disease (CD) who lose response to the standard ustekinumab dose interval of every 8 weeks (q8w) undergo dose intensification to q4w or q6w. However, baseline factors that predict success or failure after dose intensification are unknown. We sought to identify predictors of failure of ustekinumab after dose intensification for patients with CD.

METHODS

This was a retrospective cohort study of adult CD patients undergoing ustekinumab dose intensification at a tertiary referral center between January 1, 2016, and January 31, 2019. Electronic health records were reviewed to obtain patient demographics, CD history, and laboratory data. The primary outcome was failure to achieve corticosteroid-free remission (Harvey-Bradshaw Index <5) within 12 months after intensification. The secondary outcome assessed was time to new biologic therapy after dose intensification. We used multivariable logistic regression and Cox regression to identify predictors of these outcomes.

RESULTS

We included 123 patients who underwent ustekinumab dose intensification to q4w (n = 64), q5w (n = 1), q6w (n = 55), or q7w (n = 3). Multivariable logistic regression demonstrated that perianal disease, Harvey-Bradshaw Index, and opioid use at time of intensification were associated with failure to achieve remission. Cox regression demonstrated that perianal disease and corticosteroid use at time of intensification were associated with shorter time to a new biologic.

CONCLUSION

Perianal disease, Harvey-Bradshaw Index, current opioid use, and current corticosteroid use are associated with ustekinumab failure after dose intensification in CD. Larger, prospective studies are needed to corroborate these findings and guide therapeutic strategies for patients who lose response to standard ustekinumab dosing.

Long-term outcomes in perianal fistulizing Crohn's disease in a resource-limited setting: A cohort analysis

BACKGROUND

Perianal fistula is one of the most challenging complications of Crohn's disease (CD). We aimed to describe treatment response with surgical and medical therapies, and long-term complications.

METHODS

We retrospectively analyzed records of patients with perianal fistulizing CD who were prospectively followed from January 2005 to December 2018.

RESULTS

Among 807 patients, 81 (10%) had perianal fistula and 65 were included in the final analysis. The mean age of presentation was 27.4 ± 10.3 years, and 78.5% were males with a median duration of follow-up of 45 (IQR, 24-66) months. 75.4% (n = 49) had complex fistulae. 55.4% (n = 36) of patients received multiple courses (> 5 courses) of antibiotics. Complete response rates with immunomodulators, fistula surgery, biologicals, and diversion were 25%, 42.8%, 39.5%, and 45.4%, respectively. The relapse rate was highest after fistula surgery (52.6%). 44.6% of patients received medical (immunomodulators-21 and biologicals-8) whereas 46.1% received surgery as the first-line therapy. The absence of perianal abscess was associated with complete fistula closure. One patient developed malignancy and 4 (6.1%) died at the end of follow-up. Among the patients (n = 28) who received biologicals, TB reactivation occurred in one patient (3.5%).

CONCLUSION

Medical therapy should be offered as first-line therapy, and immunomodulators can be considered when patients cannot afford biologicals. Surgery offers temporary improvement and is associated with high relapse rates. Absence of perianal abscess predicts long-term complete fistula closure.

Perianal Crohn's Disease

A 22-year-old man presents to your office with a perianal abscess and occasional mild crampy abdominal pain. You take him to the operating room for an examination under anesthesia (EUA) with incision and drainage of the abscess and note a transphincteric fistula tract through which you place a seton and 2 large skin tags. The anal canal and rectum are without ulceration, but there are mild proctitis and nonprolapsing internal hemorrhoids. Because of a concern for Crohn's disease (CD), he undergoes magnetic resonance enterography and colonoscopy. The magnetic resonance enterography shows inflammation in 20 cm of the distal terminal ileum, and colonoscopy reveals approximately 10 ulcers <5 mm in the terminal ileum without significant narrowing. He is seen in consultation for the initiation of a monoclonal antibody and returns to see you in the office after his first 3 infusions. He is feeling well, has significantly decreased drainage from the perianal fistula, but would really like his seton and skin tags removed while you are there.

The Cost of Inflammatory Bowel Disease Management Matches with Clinical Course: A Single Outpatient Centre Analysis

Inflammatory bowel diseases (IBD) have a large economic burden on health systems. Our single-centre observational retrospective study aimed to assess an economic evaluation in two IBD outpatient cohorts (biological and conventional therapy) in relation to disease activity within a three-year follow-up. Four hundred and seventeen consecutive IBD patients referred to our tertiary gastroenterology unit (Bari-Puglia-Southern Italy) on January 2014–December 2016 were included. For each group (conventional/biological), we assessed direct/indirect costs and clinical/endoscopic activity within the first year and along the three-year follow-up. Statistical analyses: Wilcoxon signed-rank test (continuous variables), chi-square and Fisher’s test (categorical variables), Spearman ranks (single outcome) and ANOVA (detection time, clinical/endoscopic scores) were used. Continuous variables were expressed as mean ± standard deviation and range and/or median, interquartile range and range; categorical variables were expressed as proportions with 95% confidence interval. Direct and indirect cost items of 2014 and 2014–2016 were higher in patients treated with biological than conventional therapy. Subjects on biological therapy were younger and showed clinical and endoscopic moderate-to-severe disease activity. After three years, they reached a significant improvement from baseline. Conversely, disease activity was mild when conventional treatment had a beneficial effect. In conclusion, overall IBD management cost matches with clinical course and needs long-term evaluation in critical patients.

Optimized timing of using infliximab in perianal fistulizing Crohn's disease

Infliximab (IFX), as a drug of first-line therapy, can alter the natural progression of Crohn’s disease (CD), promote mucosal healing and reduce complications, hospitalizations, and the incidence of surgery. Perianal fistulas are responsible for the refractoriness of CD and represent a more aggressive disease. IFX has been demonstrated as the most effective drug for the treatment of perianal fistulizing CD. Unfortunately, a significant proportion of patients only partially respond to IFX, and optimization of the therapeutic strategy may increase clinical remission. There is a significant association between serum drug concentrations and the rates of fistula healing. Higher IFX levels during induction are associated with a complete fistula response in these patients. Given the apparent relapse of perianal fistulizing CD, maintenance therapy with IFX over a longer period seems to be more beneficial. It appears that patients without deep remission are at an increased risk of relapse after stopping anti-tumor necrosis factor agents. Thus, only patients in prolonged clinical remission should be considered for withdrawal of IFX treatment when biomarker and endoscopic remission is demonstrated, especially when the hyperintense signals of fistulas on T2-weighed images have disappeared on magnetic resonance imaging. Fundamentally, the optimal timing of IFX use is highly individualized and should be determined by a multidisciplinary team.

Crohn's disease

Crohn's disease is an inflammatory bowel disease that is characterized by chronic inflammation of any part of the gastrointestinal tract, has a progressive and destructive course and is increasing in incidence worldwide. Several factors have been implicated in the cause of Crohn's disease, including a dysregulated immune system, an altered microbiota, genetic susceptibility and environmental factors, but the cause of the disease remains unknown. The onset of the disease at a young age in most cases necessitates prompt but long-term treatment to prevent disease flares and disease progression with intestinal complications. Thus, earlier, more aggressive treatment with biologic therapies or novel small molecules could profoundly change the natural history of the disease and decrease complications and the need for hospitalization and surgery. Although less invasive biomarkers are in development, diagnosis still relies on endoscopy and histological assessment of biopsy specimens. Crohn's disease is a complex disease, and treatment should be personalized to address the underlying pathogenetic mechanism. In the future, disease management might rely on severity scores that incorporate prognostic factors, bowel damage assessment and non-invasive close monitoring of disease activity to reduce the severity of complications.

Incidence and Outcomes of Perianal Disease in an Asian Population with Crohn's Disease: A Nationwide Population-Based Study

BACKGROUND

Little is known about the natural history of perianal fistulas in Asian populations with Crohn's disease (CD).

AIMS

We investigated the incidence and outcomes of perianal CD (pCD) in Korean CD patients.

METHODS

A nationwide population-based cohort of 6265 CD patients diagnosed in 2010-2014 was analyzed to investigate the incidence and outcomes of pCD. The results were validated in a hospital-based cohort of 2923 CD patients diagnosed in 1981-2015. Factors associated with pCD development were analyzed. The incidence and outcomes of pCD were compared between the prebiologic and biologic eras.

RESULTS

pCD occurred in 39.2% of the population-based cohort and 56.1% of the hospital-based cohort during the median follow-up of 4.2 and 8.5 years, respectively. The cumulative incidence of pCD was 40.0% at 5 years after CD diagnosis in the population-based cohort and 62.5% at 20 years in the hospital-based cohort. In multivariate analysis, pCD development was positively associated with male sex, younger age and colonic involvement at diagnosis, early diagnosis, and CD diagnosis in the prebiologic era. The cumulative probability of proctectomy at 10, 20, and 30 years after pCD diagnosis was 2.9%, 12.2%, and 16.2%, respectively. The cumulative incidence of pCD occurring after CD diagnosis and the cumulative probability of proctectomy were significantly lower in the biologic era than in the prebiologic era (p < 0.001 and p = 0.03, respectively).

CONCLUSIONS

Compared with Western patients with CD, Korean patients show a high incidence of pCD but have a low probability of proctectomy, suggesting the favorable course of pCD.

Prevalence of Fistulizing Crohn's Disease in the United States: Estimate From a Systematic Literature Review Attempt and Population-Based Database Analysis

BACKGROUND

Fistulas may arise as a relevant complication of Crohn's disease (CD). Despite their clinical significance and the substantial burden imposed on patients, limited data are available on the epidemiology of fistulizing CD in the United States.

METHODS

A systematic literature review was conducted to identify data published between 1970 and 2017 on the epidemiology of fistulas in patients with CD, with the aim to estimate the number of prevalent cases in the United States. Retrieved titles and abstracts were screened by 2 independent researchers for inclusion criteria (US population-based studies reporting data on the epidemiology of fistulizing CD). To validate the literature-based estimate, data from a US claims database (Truven Health MarketScan database) were analyzed. This database has broad geographic coverage, with health care data for >60 million patients during the period of the analysis.

RESULTS

The literature search retrieved 7 articles for full-text review, and only 1 met the criteria for inclusion. This study described the cumulative incidence of fistulas in a CD population from Minnesota over 20 years. From the reported data, the estimated number of prevalent cases with fistulizing CD in the United States was ~76,600 in 2017 (~52,900 anal, ~7400 rectovaginal, ~2300 enterocutaneous, and ~14,100 internal). Analysis from the US health care database resulted in an estimated number of ~75,700 patients, confirming the robustness of the original estimate from the literature.

CONCLUSIONS

Based on 2 separate analyses, the estimated number of patients with fistulizing CD in the United States is ~77,000 patients.

Commonly Used Immunosuppressives Affect Mesenchymal Stem Cell Viability and Function: Should We Rethinking Clinical Trial Inclusion and Exclusion Criteria?

Background

Clinical trials utilizing mesenchymal stem cells (MCSs) for the treatment of perianal Crohn disease are expanding. Most enrolled Crohn patients are being actively treated with corticosteroids, immunomodulators, and biologic therapy for their luminal and perianal disease at the time of enrollment and treatment.

Aim

We sought to broaden the understanding of the effect of corticosteroids, immunomodulators, and biologic therapy on the viability and function of MCSs. This information is important for tailoring inclusion and exclusion criteria of clinical trials.

Methods

Human adipose–derived mesenchymal stem cells (hAMCSs) were harvested and isolated from healthy patient donors. At Passage 3, hAMCSs were treated with 7 commonly used immunosuppressive therapies used to treat Crohn disease at increasing concentrations: dexamethasone, methotrexate, azathioprine, 6-mercaptopurine, infliximab, vedolizumab, and ustekinumab. Cell proliferation, migration, and cytokine secretion were analyzed at Day 4.

Results

Dexamethasone and azathioprine and 6-mercaptopurien affected cell proliferation and migration. Dexamethasone even resulted in cell death at high physiologic concentrations. The same drugs also had the most profound impacts on IL-6, IL-8, and monocyte chemoattractant protein-1 secretion profiles. Biologic therapies, including anti-tumor necrosis factor, anti-interleukin, and anti-integrins, had the smallest impact on hAMSC proliferation, migration, and cytokine secretion profile.

Conclusions

In clinical trials with MCSs, a washout period may be recommended for corticosteroids and immunomodulators to minimize any effect of systemic immunosuppression on MSC function and efficacy.