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

Management of Perianal Fistulizing Crohn's Disease

Perianal fistulizing Crohn's disease (CD) represents a severe phenotype of CD that is associated with significant morbidity and reduction in quality of life. Perianal fistulizing CD is caused by a complex interplay of genetic predisposition, immune dysregulation, gut dysbiosis, and various unknown physiological and mechanical factors. A multidisciplinary approach is hence required for optimal management . A detailed anatomical description and classification of perianal fistula, including comprehensive clinical, endoscopic, and radiological diagnostic workup, is an important prerequisite to treatment. For simple perianal fistulas, use of antibiotics and immunomodulators, with or without fistulotomy, are appropriate measures. The medical management of complex perianal fistula, on the other hand, requires adequate control of infection before initiation of therapy with immunomodulators. In active complex perianal fistula, anti-tumor necrosis factors remain the most accepted therapy, with concomitant use of antibiotics or immunomodulators enhancing the efficacy. For patients refractory to anti-tumor necrosis factors, treatment with anti-integrins, anti-interleukins, and small molecules is being evaluated. Mesenchymal stem cells, hyperbaric oxygen therapy, and exclusive enteral nutrition have also been investigated as adjunct therapies. Despite the expansion of the medical armamentarium, a large proportion of the patients require surgical interventions. In this review, we provide an up-to-date overview of the pathophysiology, clinical presentation, diagnosis, and medical management of perianal fistulizing CD. A brief overview of the surgical management of perianal fistulizing CD is also provided.

Fistulizing Perianal Disease as a First Manifestation of Crohn's Disease: A Systematic Review and Meta-Analysis

Background: Incidences of perianal fistulas (PAFs) as a first manifestation of Crohn's disease (CD) vary widely in the literature. Aim: To analyse the percentage of patients with a PAF preceding CD diagnosis and assess the time to diagnosis. Methods: A systematic literature search was conducted. Studies reporting on patients with a PAF preceding CD diagnosis were identified. Primary outcomes were the (weighted) percentage of patients with CD with a PAF preceding CD and their time to CD diagnosis. Secondary outcomes were the (weighted) percentage of patients with CD with a PAF preceding CD diagnosis in predefined patient subgroups, including (1) sex (men vs. women), (2) ethnicity (Asian vs. non-Asian), and (3) age (paediatric (0-18 y) and patients with elderly onset CD (>60 y) vs. adult patients (18-60 y)). Results: Seventeen studies were included (34,030 patients with CD). In the overall CD population, a PAF preceded CD in 8.6% [95%CI; 5.72; 12.71] with a weighted mean time to CD diagnosis of 45.9 (31.3) months. No studies reported details on sex differences in patients with a PAF as a manifesting sign of CD. In Asian populations, a PAF preceded CD in 17.66% [95%CI; 11.45; 26.25], which was significantly higher when compared with non-Asians (4.99% [95%CI; 3.75; 6.60], OR:3.99, p < 0.0001). In adolescents, an incidence of 9.17% [95%CI; 5.92; 13.93] was found with significantly lower incidences in paediatric patients (6.38% [95%CI; 1.84; 19.85], OR:0.53, p < 0.0001), and elderly-onset patients (3.77% [95%CI; 1.68; 8.25], OR:0.44, p = 0.0035). Conclusions: This systematic review shows that in the literature, almost 10% of patients present with a PAF as a first manifestation of CD, with a mean time to diagnosis of almost four years. These results emphasise that increased clinical awareness is needed.

Multimodal single-cell analyses reveal mechanisms of perianal fistula in diverse patients with Crohn's disease

BACKGROUND

Crohn's disease complicated by perianal fistulae is more prevalent and severe in patients of African ancestry.

METHODS

We profiled single cells from diverse patients with Crohn's disease with perianal fistula from colorectal mucosa and fistulous tracts. Immunofluorescence was performed to validate predicted cell-cell interactions. Unstimulated monocytes were chronically cultured in diverse cohorts. A subset was analyzed by single-nucleus RNA + ATAC sequencing.

FINDINGS

Fistulous tract cells from complete proctectomies demonstrated enrichment of myeloid cells compared to paired rectal tissues. Ligand-receptor analysis highlights myeloid-stromal cross-talk and cellular senescence, with cellular co-localization validated by immunofluorescence. Chitinase-3 like-protein-1 (CHI3L1) is a top upregulated gene in stromal cells from fistulae expressing both destructive and fibrotic gene signatures. Monocyte cultures from patients of African ancestry and controls demonstrated differences in CHI3L1 and oncostatin M (OSM) expression upon differentiation compared to individuals of European ancestry. Activating protein-1 footprints are present in ATAC-seq peaks in stress response genes, including CHI3L1 and OSM; genome-wide chromatin accessibility including JUN footprints was observed, consistent with reported mechanisms of inflammatory memory. Regulon analyses confirm known cell-specific transcription factor regulation and implicate novel ones in fibroblast subsets. All pseudo-bulked clusters demonstrate enrichment of genetic loci, establishing multicellular contributions. In the most significant African American Crohn's genetic locus, upstream of prostaglandin E receptor 4, lymphoid-predominant ATAC-seq peaks were observed, with predicted RORC footprints.

CONCLUSIONS

Population differences in myeloid-stromal cross-talk implicate fibrotic and destructive fibroblasts, senescence, epigenetic memory, and cell-specific enhancers in perianal fistula pathogenesis. The transcriptomic and epigenetic data provided here may guide optimization of promising mesenchymal stem cell therapies for perianal fistula.

FUNDING

This work was supported by grants U01DK062422, U24DK062429, and R01DK123758.

Ten missteps in the management of inflammatory bowel disease in Asia: An expert report by the Asian Pacific Association of Gastroenterology Working Group on Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is rapidly emerging in the Asia Pacific region. However, there are many challenges in the diagnosis and management of this condition. The Asian Pacific Association of Gastroenterology (APAGE) Working Group on IBD conducted a round table meeting to identify 10 common mistakes in the management of IBD in Asia. To summarize, many physicians still over rely on a definitive histological diagnosis before starting treatment and do not fully establish disease extent such as perianal and proximal gastrointestinal involvement in Crohn's disease (CD) or extent of involvement in ulcerative colitis (UC). It is also essential to actively look for evidence of extra-intestinal manifestations, which may influence choice of therapy. In terms of conventional therapy, underuse of topical 5 aminosalicylates (5-ASAs) in UC and inappropriate dosing of corticosteroids are also important considerations. Acute severe UC remains a life-threatening condition and delay in starting rescue therapy after inadequate response to intravenous steroids is still common. Anti-tumor necrosis factors should be considered first line in all cases of complex perianal fistulizing CD. Most patients with IBD are on potent immunosuppressive therapy and should be screened for latent infections and offered vaccinations according to guidelines. Under-recognition and management of significant complications such as anemia, osteoporosis, malnutrition, and thromboembolism should also be addressed. Colonoscopy is still not properly performed for dysplasia/cancer surveillance and for evaluating post-op recurrence of CD. Another common misstep is inappropriate withdrawal of medications during pregnancy leading to increased complications for the mother and the newborn.

Perianal disease in inflammatory bowel disease: Broadening treatment and surveillance strategies for anal cancer

The perianal disease affects up to one-third of individuals with Crohn's disease (CD), causing disabling symptoms and significant impairment in quality of life, particularly for those with perianal fistulising CD (PFCD). The collaborative effort between gastroenterologists and surgeons is essential for addressing PFCD to achieve fistula closure and promote luminal healing. Limited fistula healing rates with conventional therapies have prompted the emergence of new biological agents, endoscopic procedures and surgical techniques that show promising results. Among these, mesenchymal stem cells injection is a particularly hopeful therapy. In addition to the burden of fistulas, individuals with perianal CD may face an increased risk of developing anal cancer. This underscores the importance of surveillance programmes and timely interventions to prevent late diagnoses and poor outcomes. Currently, there is no established formal anal screening programme. In this review, we provide an overview of the current state of the art in managing PFCD, including novel medical, endoscopic and surgical approaches. The discussion also focuses on the relevance of establishing an anal cancer screening programme in CD, intending to propose a risk-based surveillance algorithm. The validation of this surveillance programme would be a significant step forward in improving patient care and outcomes.

Use of Darvadstrocel (Allogenic Stem Cell Therapy) for Crohn's Fistulas in Real Clinical Practice: The National Project to Implement Mesenchymal Stem Cell for the Treatment of Perianal Crohn's Fistula (the PRIME Study)

BACKGROUND

Perianal fistulas may affect 15% to 50% of patients with Crohn's disease. Treatment is complex, requiring a multidisciplinary approach. Darvadstrocel (allogenic mesenchymal cells obtained from lipoaspirates) was approved in 2018 by the European and Spanish Agencies of Medicines and Medical Products as a treatment for fistulas in Crohn's disease. Recent guidelines from the European Crohn's and Colitis Organisation and Spanish Working Group on Crohn's Disease and Ulcerative Colitis state that darvadstrocel is effective with a favorable safety profile and a strong level of evidence (n = 2).

OBJECTIVE

Presenting real-world effectiveness data for darvadstrocel in a Spanish population.

DESIGN

Observational retrospective cohort study with prospective data gathering.

SETTINGS

The study was conducted at 14 institutions in Spain.

PATIENTS

From November 2019 to April 2022, all patients (n = 73) treated with darvadstrocel in these institutions were included, fulfilling the following criteria: 1) complex fistula/s in a patient with Crohn's disease; 2) failure of conventional and antitumor necrosis factor treatment; and 3) the absence of collections of >2 cm confirmed by pelvic MRI at the time of surgery.

INTERVENTIONS

Darvadstrocel treatment.

MAIN OUTCOME MEASURES

Clinical response (closure of 50% or more of external openings), complete clinical closure (100% of external openings), and radiological closure (no fluid collection >2 cm, edema, or inflammation) evaluated 6 months after treatment.

RESULTS

Clinical response was observed in 63 patients (86.3%), complete clinical closure in 50 patients (68.5%), and radiological closure in 45 patients (69.2%). Combined clinical and radiological response was observed in 41 patients (63.1%). Not all clinically healed patients had radiological closure, and vice versa. No serious adverse events were reported.

LIMITATIONS

Retrospective nature of the study.

CONCLUSIONS

Study results were consistent with those reported in previous clinical trials, real-world efficacy findings from the INSPIRE study (assessing darvadstrocel effectiveness in Europe, Israel, Switzerland, United Kingdom, and Japan), and previously published literature. Darvadstrocel was effective and demonstrated a favorable safety profile when used in normal clinical practice for the treatment of fistulas in Crohn's disease. See Video Abstract .

USO DE DARVADSTROCEL TERAPIA CON CLULAS MADRE ALOGNICAS PARA FSTULA EN ENFERMEDAD DE CROHN EN LA PRCTICA CLNICA REAL EL PROYECTO NACIONAL PARA IMPLEMENTAR DE CLULAS MADRE MESENQUIMALES PARA EL TRATAMIENTO DE LA FSTULA DE CROHN PERIANAL EL ESTUDIO PRIME

ANTECEDENTES:Las fístulas perianales pueden afectar entre el 15 y el 50% de los pacientes con enfermedad de Crohn. El tratamiento es complejo y requiere un enfoque multidisciplinario. El darvadstrocel (células mesenquimales alogénicas obtenidas a partir de lipoaspirados) fue aprobado en 2018 por las Agencias Europea y Española de Medicamentos y Productos Sanitarios como tratamiento de las fístulas en la EC. Las recientes directrices de la Organización Europea de Crohn y Colitis y del Grupo de Trabajo Español sobre la Enfermedad de Crohn y Colitis Ulcerosa afirman que darvadstrocel es eficaz con un perfil de seguridad favorable y un sólido nivel de evidencia (2).OBJETIVO:Presentar datos de eficacia real de darvadstrocel en población española.DISEÑO:Estudio de cohorte retrospectivo observacional con recopilación prospectiva de datos.ESCENARIO:14 instituciones.PACIENTES:Desde noviembre de 2019 hasta abril de 2022, se incluyeron todos los pacientes (73) tratados con darvadstrocel en estas instituciones, que cumplieron los siguientes criterios: 1) fístula/s compleja/s en un paciente con enfermedad de Crohn; 2) fracaso del tratamiento convencional y anti factor de necrosis tumoral; 3) ausencia de colecciones > 2 cm confirmada por resonancia magnética pélvica en el momento de la cirugía.INTERVENCIONES:Tratamiento con Darvadstrocel.PRINCIPALES MEDIDAS DE RESULTADO:Respuesta clínica (cierre de ≥50% de las aberturas externas), cierre clínico completo (100% de las aberturas externas) y cierre radiológico (sin acumulación de líquido >2 cm, sin edema ni inflamación) evaluados 6 meses después del tratamiento.RESULTADOS:Se observó respuesta clínica en 63 pacientes (86.3%), cierre clínico completo en 50 pacientes (68.5%) y cierre radiológico en 45 pacientes (69.2%). Se observó respuesta clínica y radiológica combinada en 41 pacientes (63.1%). No todos los pacientes clínicamente curados tuvieron cierre radiológico y viceversa. No hubo eventos adversos graves reportados.LIMITACIONES:Estudio retrospectivoCONCLUSIONES:Los resultados del estudio fueron consistentes con los informados en ensayos clínicos anteriores, los hallazgos de eficacia en el mundo real del estudio INSPIRE (que evalúa la efectividad de darvadstrocel en Europa, Israel, Suiza, el Reino Unido y Japón) y la literatura publicada anteriormente. Darvadstrocel fue eficaz y demostró un perfil de seguridad favorable cuando se utiliza en la práctica clínica habitual para el tratamiento de fístulas en la enfermedad de Crohn. (Traducción-Dr. Jorge Silva Velazco ).

Prevalence, incidence, and treatment patterns of fistulizing Crohn disease: A US population-based cohort study

BACKGROUND

Population-based studies for patients with fistulizing Crohn disease (CD), a severe complication of CD, are limited.

OBJECTIVE

To report estimates of the prevalence and incidence rates of fistulizing CD in the United States and examine associated treatment patterns among incident cases.

METHODS

This retrospective, observational cohort study used a US administrative claims database from January 1, 2016, to December 31, 2019, with at least 365 days' continuous insurance enrollment. The prevalent patient population comprised patients with incident or existing cases of fistulizing CD. Crude, age, and sex-adjusted prevalence and incidence rates of fistulizing CD were estimated. Baseline characteristics, comorbidities, and CD-related medications and medical procedures were examined for patients with fistulizing CD.

RESULTS

The overall crude prevalence (prevalent cases: n = 5,082) and incidence rates (incident cases: n = 2,399) between 2017 and 2019 were 25.2 (95% CI = 24.5-25.9) per 100,000 persons and 6.9 (95% CI = 6.6-7.1) per 100,000 person-years, respectively. Age- and sex-adjusted prevalence and incidence rates were 24.9 (95% CI = 24.2-25.6) per 100,000 persons and 7.0 (95% CI = 6.7-7.3) per 100,000 person-years, respectively. Approximately half of all patients with incident fistulizing CD were prescribed biologic therapies within 1 year of an incident fistula diagnosis, with anti-tumor necrosis factor therapies the most widely prescribed biologic class; antibiotic and corticosteroid use was also common. Among the incident cases, approximately one-third of patients required surgery during the follow-up period, most of which occurred within 3 months of the index date.

CONCLUSIONS

This study reports age- and sex-adjusted prevalence and incidence rates for fistulizing CD of 24.9 per 100,000 persons and 7.0 per 100,000 person-years, respectively. As a concerning complication of CD, first-year treatment of fistulas in the United States commonly includes anti-tumor necrosis factor therapy, and there is a considerable surgical burden.

Characteristics, Clinical Outcomes, and Prognosis of Anal and Pouch-related Carcinoma in Patients With Crohn's Disease

BACKGROUND

This study described the clinical characteristics, outcomes, and prognosis of Crohn's disease (CD) patients with anal cancer in a tertiary referral center.

METHODS

The electronic medical records of 35 adult CD patients, including CD of the pouch, with anal carcinoma evaluated at Mayo Clinic Rochester, Florida, or Arizona between January 1989 and August 2022 were retrospectively reviewed.

RESULTS

Before cancer diagnosis, patients with pouch-related carcinoma had a shorter median duration of inflammatory bowel disease than those with anal carcinoma (10 vs 26 years). Twenty-six patients (74%) had perianal diseases or rectovaginal fistula, and 35% had a history of human papillomavirus infection. Twenty-one patients (60%) were diagnosed with cancer by anal examination under anesthesia (EUA). More than half of adenocarcinomas were mucinous. Sixteen patients (47%) were American Joint Committee on Cancer (AJCC) Tumor Nodes Metastasis (TNM) stage 3, and 83% were treated by surgery. At last follow-up, 57% of patients were alive without cancer. The 1-, 3- and 5-year overall survival rates were 93.8% (95% confidence interval [CI], 85.7%-100%), 71.5% (95% CI, 56.4%-90.7%), and 67.7% (95% CI, 51.2%-87.7%), respectively. Advanced AJCC TNM stage (hazard ratio, 3.20 per stage; 95% CI, 1.05-9.72; P = .040) was significantly associated with increased risk of death, whereas the period of cancer diagnosis in 2011-2022 (HR, relative to 1989-2000, 0.16; 95% CI, 0.04-0.72; P = .017) was significantly related to decreased risk of death.

CONCLUSIONS

Anal and pouch-related carcinomas were rare complications of CD, and long-standing perianal diseases were an important risk factor. Anal EUA improved the diagnostic yield. Newer cancer treatment strategies and surgery were associated with excellent survival outcome.

Perianal Fistula; from Etiology to Treatment - A Review

Anal fistula has been a challenging clinical issue for years due to its complex pathogenesis. The risk of frequent recurrence and incontinence complicates long-term treatment. Recent scientific literature has reviewed new techniques used for anal fistula treatment in recent years, assessing the advantages and disadvantages of each based on clinical outcomes. Although surgery is the main method used to treat anal fistula, there is no simple technique that can completely heal complex anal fistula. The surgical treatment should consider the healing outcome and the protection of anal function comprehensively. Several innovative techniques have emerged in recent years, such as combined techniques based on drainage seton and LIFT-plug, which appear to be relatively effective therapies. However, more multi-center prospective trials with long-term follow-up are needed to validate their effectiveness. In some situations, medical treatment may also be considered.

Perianal disease: Updates and controversies in closing the gaps

Perianal complications are common and morbid in children with Crohn's disease. In this review, we describe the epidemiology, the presentation and diagnosis, evaluation and management. We focus on updates such as the increasing frequency of biologic medications and MRI for evaluation. We also highlight controversies on the timing and approaches to surgical techniques. Finally, perianal disease requires the coordination of multidisciplinary care with nursing, radiology, gastroenterology, and surgery to optimize outcomes - both medical and patient-centered.

Perianal Mucinous Adenocarcinoma: A Case of Recurrent Anal Fistula

An anal fistula is a fairly common clinical condition, with a very low incidence of malignant transformation. Mucinous adenocarcinoma is a subtype of adenocarcinoma, and its occurrence within perianal fistula tracts is quite rare. This case report describes a 54-year-old male patient with recurrent anal fistula, initially suspected of Crohn's disease (CD), and ultimately diagnosed with perianal mucinous adenocarcinoma. After our joint internal medicine, surgery, and imaging reassessment, the diagnosis was confirmed. Anal fistula is usually considered a benign lesion, but it may also be associated with other diseases. Due to overlapping symptoms of related diseases, the investigation of malignant lesions is often overlooked. This case report emphasizes the importance of timely referral and multidisciplinary management for disease diagnosis and early treatment.

Editorial: The prevalence and outcomes of perianal Crohn's disease across the treatment eras-Authors' reply

This article is linked to Gonczi et al papers. To view these articles, visit https://doi.org/10.1111/apt.17836 and https://doi.org/10.1111/apt.17861

Burden of perianal disease in Crohn's disease: Accelerating medical therapy and high rates of perianal surgery over the last four decades - Results from a population-based study over four decades

BACKGROUND

Few population-based studies have investigated the prevalence and disease course of perianal manifestation in Crohn's disease.

AIMS

To analyse the prevalence and outcomes of perianal Crohn's disease including medical therapies and need for perianal surgery, over different therapeutic eras based on the time of diagnosis; cohort A (1977-1995), cohort B (1996-2008), and cohort C (2009-2018) METHODS: Patient inclusion lasted between 1977 and 2018. We followed patients prospectively, and regularly reviewed both in-hospital and outpatient records. We defined a perianal surgical procedure as any perianal incision and excision, fistulotomy, or abscess drainage.

RESULTS

We included 946 incident patients. Perianal disease at diagnosis was present in 17.4% (n = 165) of the total cohort, with a declining prevalence in cohorts A/B/C, respectively (24.7%/18.5%/13.2%; p = 0.001). By the end of follow-up, an additional 9.3% (n = 88) of the total cohort developed perianal disease. Cumulative immunosuppressive and biologic exposure increased over time; biologic use was higher in patients with perianal disease [pLog Rank < 0.001]. The overall rate of perianal surgery was 44.7% (113/253), with a probability of 28.3% (95% CI: 25.4-31.2) after 10 years, 41.0% (95% CI: 37.5-44.5) after 20 years, and 64.1% (95% CI: 59-69.2) after 30 years. There was no statistically significant difference in the probability of first perianal surgery among cohorts A/B/C [Log Rank = 0.594].

CONCLUSIONS

The burden of perianal disease and perianal surgery rates were high in this cohort. Therapeutic strategy was accelerated in patients with perianal Crohn's over time with higher exposure to immunosuppressives and biologics. Surgical management of perianal disease remained unchanged amongst the cohorts.

Comparative Effectiveness of Biologic Therapies in Preventing Penetrating Complications in Patients With Crohn's Disease

BACKGROUND & AIMS

Comparative effectiveness of biologics in preventing penetrating disease (PD) in Crohn's disease (CD) is not well established. We compared the risk of developing luminal and perianal PD (LPD and PPD) between biologics used as first-line therapies.

METHODS

Adults (>17 years) with CD who initiated their first biologic (anti-tumor necrosis factor [anti-TNF], ustekinumab [UST], or vedolizumab [VDZ]) were identified from Merative Commercial Database (2006 and 2020). We excluded preexisting PD using a minimum look-back period of 1 year. Cohorts were balanced by inverse probability of treatment weighting based on age, sex, comorbidities, prior CD surgery, and CD severity. Pairwise comparisons were performed by Cox proportional hazards models, adjusted for immunomodulator exposure, and with biologic exposure treated as a time-dependent variable based on a medication possession ratio of 0.8.

RESULTS

Our analysis included 40,693 patients: 93% anti-TNF, 3% UST, and 4% VDZ. After inverse probability of treatment weighting all comparisons were well balanced. Anti-TNF was protective against LPD (hazard ratio, 0.66; 95% confidence interval, 0.55-0.78; P < .0001) and PPD (hazard ratio, 0.88; 95% confidence interval, 0.80-0.96; P = .0045) compared with VDZ and LPD (hazard ratio, 0.37; 95% confidence interval, 0.30-0.46; P < .0001) compared with UST. There were no significant differences in the risk of LPD and PPD between VDZ and UST. These results were similar after limiting the study period to after 2016.

CONCLUSIONS

Anti-TNF therapy was associated with a lower risk of LPD and PPD compared with VDZ, and lower risk of LPD compared with UST. Further studies are needed to validate these findings and to determine potential reasons for these differences.

Efficacy and Safety of Hyperbaric Oxygen Therapy in Fistulizing Crohn's Disease: A Systematic Review and Meta-analysis

BACKGROUND

Hyperbaric oxygen therapy (HBOT) delivers 100% oxygen in a pressurized chamber, increasing tissue oxygen levels and regulating inflammatory pathways. Mounting evidence suggests that HBOT may be effective for inflammatory bowel disease. Our systematic review and meta-analysis aimed to quantify the efficacy and safety of HBOT in fistulizing Crohn's disease (CD).

METHODS

A systematic review was conducted using the EMBASE, Web of Science, Pubmed, and Cochrane Library databases according to the "Preferred Reporting Items for Systematic Reviews and Meta-analyses" criteria. Study bias was assessed using the Cochrane Handbook guidelines.

RESULTS

Sixteen studies with 164 patients were included in the analysis. For all fistula subtypes, the pooled overall clinical response was 87% (95% CI: 0.70-0.95, I2 = 0) and the pooled clinical remission was 59% (95% CI: 0.35-0.80, I2 = 0). The overall clinical response was 89%, 84%, and 29% for perianal, enterocutaneous, and rectovaginal fistulas, respectively. On meta-regression, hours in the chamber and the number of HBOT sessions were not found to correlate with clinical response. The pooled number of adverse events was low at 51.7 per 10,000 HBOT sessions for all fistula types (95% CI: 16.8-159.3, I2 = 0). The risk of bias was observed across all studies.

CONCLUSION

HBOT is a safe and potentially effective treatment option for fistulizing CD. Randomized control trials are needed to substantiate the benefit of HBOT in fistulizing CD.

Efficacy of IL-23 inhibitors and IL-12/23 inhibitors in the induction treatment of Crohn's disease: A meta-analysis based on randomized controlled trials

Introduction

A growing number of randomized controlled trials (RCTs) have demonstrated the effectiveness of interleukin (IL)-23 and IL-12/23 inhibitors in treating Crohn's disease (CD). This study evaluated the efficacy of IL-23 and IL-12/23 inhibitors in the induction phase for the treatment of CD.

Material and methods

We searched the following databases from inception until December, 2022: Medline, Embase, Web of Science and the Cochrane Library. The primary outcome was the proportion of CD patients who achieved clinical remission at the end of the induction therapy period. Secondary outcomes included clinical response, endoscopic remission, endoscopic response and normalized C-reactive protein (CRP).

Results

After screening, 7 RCTs were included in our study. The meta-analysis showed that, in the induction period, more patients treated with IL-23 inhibitors and IL-12/23 inhibitors achieved clinical remission than patients with placebo therapy (RR = 2.11, 95% CI: 1.83-2.44; RR = 1.94, 95% CI: 1.64-2.29; respectively). The IL-23 inhibitor group and the IL-12/23 inhibitor group showed higher clinical response rates than the placebo group (RR = 1.92, 95% CI: 1.74-2,11; RR = 1.83, 95% CI: 1.61-2.09; respectively). In addition, the IL-23 inhibitor group had a higher endoscopic remission rate and endoscopic response rate than the placebo group; the corresponding pooled RRs were 3.40 (95% CI: 2.57-4.50) and 2.65 (95% CI: 2.65-3.12), respectively.

Conclusions

IL-23 and IL-12/23 inhibitors were efficient methods in the induction treatment of CD.

Effectiveness and safety of darvadstrocel in patients with complex perianal fistulizing Crohn's disease: a systematic review

Background

Managing complex perianal fistulizing Crohn's disease (CD) remains challenging, despite current medical and surgical treatment approaches. Darvadstrocel, a therapy utilizing adipose-derived stem cells, shows promise in promoting tissue regeneration and healing, offering a novel and effective treatment for fistula management.

Method

A systematic literature search was conducted on PubMed and Scopus to identify studies involving patients with complex perianal fistulizing CD treated with darvadstrocel.

Results

In total, 2 randomized controlled trials (RCT), 5 observational studies with retrospective data collection and 2 observational studies with prospective design were included in the final review. Data from the European ADMIRE-CD RCT demonstrated that darvadstrocel is superior to placebo in terms of clinical and imaging improvement over both the short and long term. These findings align with the prospective studies analyzed in this systematic review. The rate of treatment-emergent adverse events in the ADMIRE-CD trial's RCTs was similar in both the darvadstrocel and control groups, with perianal abscess being the most common adverse event up to 52 weeks after drug administration. Retrospective studies indicated no side-effects beyond 52 weeks.

Conclusions

Darvadstrocel appears to be a new, potentially effective and safe treatment option for the management of complex perianal fistulas. However, more randomized clinical trials are needed to evaluate the efficacy and safety profile of the drug.

Patient and Caregiver Perspectives on Their Experiences With Crohn's Perianal Fistulas

Background

Little is known about patients' perception of care and management of Crohn's perianal fistulas (CPF). This study was conducted to understand US patient and caregiver attitudes and challenges to CPF care.

Methods

Patients with CPF and caregivers of patients with CPF completed a 36-question survey about their perceptions and challenges regarding the diagnosis, treatment, and overall management of CPF. Patients/caregivers were recruited via online Crohn's and fistula support group websites and forums and via their gastroenterologists (GEs) and surgeons from October 2020 through January 2021.

Results

The survey was completed by 96 patients and 54 caregivers. Respondents reported over 60% and 14%-23% of CPF were diagnosed and treated by a GE or surgeon, respectively. Nearly all patients/caregivers wanted to be involved in treatment decision-making with their physicians (81%). While the majority of patients/caregivers were satisfied with their quality of care (65%) and access to care (67%), racial disparities exist and there is room for improvement. A smaller proportion of non-White versus White patients/caregivers reported satisfaction with care quality (39% vs 72%, respectively) and access to care (57% vs 69%, respectively). Half of non-White patient/caregivers (50%) versus 69% of White patient/caregivers knew where to access CPF information. Most patients/caregivers (69%) stated that they would benefit from more information on managing day-to-day CPF symptoms. Significant barriers perceived by patients/caregivers to receiving optimal CPF care included lack of effective treatments (69%) and lack of access to specialist care (68%).

Conclusions

Improvements in multidisciplinary CPF care are required to optimize treatment.

Perianal Fistulas Are Associated with Persistently Higher Direct Health Care Costs in Crohn's Disease: A Population-Based Study

BACKGROUND

The economic impact of perianal fistulas in Crohn's disease (CD) has not been formally assessed in population-based studies in the biologic era.

AIM

To compare direct health care costs in persons with and without perianal fistulas.

METHODS

We performed a longitudinal population-based study using administrative data from Ontario, Canada. Adults (> 17 years) with CD were identified between 2007 and 2013 using validated algorithms. Perianal fistula positive "cases" were matched to up to 4 "controls" with CD without perianal fistulas based on age, sex, geographic region, year of CD diagnosis and duration of follow-up. Direct health care costs, excluding drug costs from private payers, were estimated annually beginning 5 years before (lookback) and up to 9 years after perianal fistula diagnosis (study completion) for cases and a standardized date for matched controls.

RESULTS

A total of 581 cases were matched to 1902 controls. The annual per capita direct cost for cases was similar at lookback compared to controls ($2458 ± 6770 vs $2502 ± 10,752; p = 0.952), maximally greater in the first year after perianal fistulas diagnosis ($16,032 ± 21,101 vs $6646 ± 13,021; p < 0.001) and remained greater at study completion ($11,358 ± 17,151 vs $5178 ± 9792; p < 0.001). At perianal fistula diagnosis, the cost difference was driven primarily by home care cost (tenfold greater), publicly-covered prescription drugs (threefold greater) and hospitalizations (twofold greater), whereas at study completion, prescription drugs were the dominant driver (threefold greater).

CONCLUSION

In our population-based cohort, perianal fistulas were associated with significantly higher direct healthcare costs at the time of perianal fistulas diagnosis and sustained long-term.

Genetic coding variant in complement factor B (CFB) is associated with increased risk for perianal Crohn's disease and leads to impaired CFB cleavage and phagocytosis

OBJECTIVE

Perianal Crohn's disease (pCD) occurs in up to 40% of patients with CD and is associated with poor quality of life, limited treatment responses and poorly understood aetiology. We performed a genetic association study comparing CD subjects with and without perianal disease and subsequently performed functional follow-up studies for a pCD associated SNP in Complement Factor B (CFB).

DESIGN

Immunochip-based meta-analysis on 4056 pCD and 11 088 patients with CD from three independent cohorts was performed. Serological and clinical variables were analysed by regression analyses. Risk allele of rs4151651 was introduced into human CFB plasmid by site-directed mutagenesis. Binding of recombinant G252 or S252 CFB to C3b and its cleavage was determined in cell-free assays. Macrophage phagocytosis in presence of recombinant CFB or serum from CFB risk, or protective CD or healthy subjects was assessed by flow cytometry.

RESULTS

Perianal complications were associated with colonic involvement, OmpC and ASCA serology, and serology quartile sum score. We identified a genetic association for pCD (rs4151651), a non-synonymous SNP (G252S) in CFB, in all three cohorts. Recombinant S252 CFB had reduced binding to C3b, its cleavage was impaired, and complement-driven phagocytosis and cytokine secretion were reduced compared with G252 CFB. Serine 252 generates a de novo glycosylation site in CFB. Serum from homozygous risk patients displayed significantly decreased macrophage phagocytosis compared with non-risk serum.

CONCLUSION

pCD-associated rs4151651 in CFB is a loss-of-function mutation that impairs its cleavage, activation of alternative complement pathway, and pathogen phagocytosis thus implicating the alternative complement pathway and CFB in pCD aetiology.

Clinical and magnetic resonance imaging spectrum of complex perianal fistulizing Crohn's disease: A cohort study from northern India

BACKGROUND

Fistulizing perianal Crohn's disease (CD) is a debilitating condition associated with significant morbidity and reduction in the quality of life. Magnetic resonance imaging (MRI) of the pelvis is the preferred imaging modality for the comprehensive assessment of the perianal fistula. There is a paucity of data from India on the MRI spectrum of complex perianal fistula in CD.

METHODS

A single-centre cross-sectional analysis of patients with fistulizing perianal CD, who underwent pelvic MRI between January 2020 and December 2021, was performed. The clinical (age, sex, disease duration, disease location and behavior, disease activity [Perianal Disease Activity Index, PDAI] and treatment received) and radiological (number and location of fistulae, extensions, number and location of internal and external openings, fistula activity, presence or absence of perianal abscess and associated proctitis) characteristics of complex perianal fistula (defined according to the American Gastroenterological Association classification) were recorded.

RESULTS

Of total 175 patients with CD who attended the gastroenterology clinic during the study period, 27 (15.42%) (mean age 42±15.5 years, 62.96% females and median disease duration four years) had complex perianal fistula and were included in the analysis. The mean PDAI was 5.48±2.53. The median Van Assche Index was 17 (interquartile range [IQR] 13-19). A majority (96.29%) of the fistulae were trans-sphincteric and four (14.81%) fistulae extended into the supralevator space. All fistulae were active on MRI. Concomitant perianal abscess and proctitis were seen in 59.26% (n=16) and 62.96% (n=17) of patients, respectively. Combination therapy with biologics and antibiotics/immune-suppressants were the most commonly prescribed medical therapy. Six (22.22%) patients underwent combined medical and surgical (non-cutting seton, fistulectomy, fecal diversion) treatment.

CONCLUSION

The cumulative risk of the development of fistulizing perianal CD in a northern Indian cohort was similar to the western populations. Complex perianal fistulae were predominantly trans-sphincteric and commoner in females. MRI evaluation is pivotal for the delineation of fistula anatomy, assessment of disease extent and activity and the evaluation of concomitant perianal abscess and other complications.

Novel Approach in Rectovaginal Fistula Treatment: Combination of Modified Martius Flap and Autologous Micro-Fragmented Adipose Tissue

In this paper, we introduce an innovative therapeutic approach for managing rectovaginal fistulas (RVF), by combining the modified Martius flap and micro-fragmented adipose tissue (MFAT) enriched with mesenchymal stem cells (MSC). This novel approach aims to deal with the difficulties associated with RVF, a medically complex condition with a lack of effective treatment options. We present the case of a 45-year-old female patient with a 15-year history of Crohn's disease (CD). During the preceding eight years, she had encountered substantial difficulties resulting from a rectovaginal fistula (RVF) that was active and considerable in size (measuring 3.5 cm in length and 1 cm in width). Her condition was accompanied by tissue alterations at both the vaginal and rectal openings. Following her admission to our hospital, the patient's case was discussed during both surgical and multidisciplinary hospital team (IRB) meetings. The team decided to combine a modified Martius flap with autologous MFAT containing MSCs. The results were remarkable, leading to comprehensive anatomical and clinical resolution of the RVF. Equally significant was the improvement in the patient's overall quality of life and sexual satisfaction during the one-year follow-up period. The integration of the modified Martius flap with MFAT emerges as a highly promising approach for addressing CD-related RVFs that had historically been, and still are, difficult to treat, given their often refractory nature and low healing success rates.

Up-to-date meta-analysis of long-term evaluations of mesenchymal stem cell therapy for complex perianal fistula

BACKGROUND

Local mesenchymal stem cell (MSC) therapy for complex perianal fistulas (PFs) has shown considerable promise. But, the long-term safety and efficacy of MSC therapy in complex PFs remain unknown.

AIM

To explore the long-term effectiveness and safety of local MSC therapy for complex PFs.

METHODS

Sources included the PubMed, EMBASE, and Cochrane Library databases. A standard meta-analysis was performed using RevMan 5.3.

RESULTS

After screening, 6 studies met the inclusion criteria. MSC therapy was associated with an improved long-term healing rate (HR) compared with the control condition [odds ratio (OR) = 2.13; 95% confidence interval (95%CI): 1.34 to 3.38; P = 0.001]. Compared with fibrin glue (FG) therapy alone, MSC plus FG therapy was associated with an improved long-term HR (OR = 2.30; 95%CI: 1.21 to 4.36; P = 0.01). When magnetic resonance imaging was used to evaluate fistula healing, MSC therapy was found to achieve a higher long-term HR than the control treatment (OR = 2.79; 95%CI: 1.37 to 5.67; P = 0.005). There were no significant differences in long-term safety (OR = 0.77; 95%CI: 0.27 to 2.24; P = 0.64).

CONCLUSION

Our study indicated that local MSC therapy promotes long-term and sustained healing of complex PFs and that this method is safe.

Management of Perianal Crohn's Disease

Perianal Crohn's disease affects 25%-35% of patients with Crohn's disease and has proven to be one of the most difficult complications of the disease to treat. Patients with perianal Crohn's disease have lower health-related quality of life scores typically related to pain and fecal incontinence. In addition, patients with perianal Crohn's disease have higher rates of hospitalizations, surgeries, and overall healthcare costs. A multidisciplinary approach is necessary for the successful management of Crohn's disease with perianal fistula. Medical management is required to treat the underlying immune dysregulation to heal the luminal inflammation and the inflammation within the fistula tracts. Current options for medical therapy include biologics, dual therapy with thiopurines, therapeutic drug monitoring, and a close follow-up. Surgical management is critical to drain abscesses before immunosuppressive therapy and place setons when appropriate. Once the patient's inflammatory burden is well managed, definitive surgical therapies including fistulotomies, advancement flaps, and ligation of intersphincteric fistula tract procedures can be considered. Most recently, the use of stem cell therapy in the treatment of perianal fistula has given new hope to the cure of perianal fistula in Crohn's disease. This review will outline the most current data in the medical and surgical management of perianal Crohn's disease.

Epidemiology, Disease Course, and Clinical Outcomes of Perianal Fistulas and Fissures Crohn's Disease: A Nationwide Population-Based Study in Taiwan

Background

Population-based data on the course of perianal disease in East Asian populations with Crohn's disease (CD) are limited. This study examined the prevalence, clinical course, and compared the outcomes of CD patients with perianal CD (pCD) versus without pCD in Taiwan.

Methods

A nationwide population-based study was implemented from 2000 to 2017 by using the Taiwan National Health Insurance Research Database.

Results

Of 2424 patients with CD, 358 (14.8%) patients with pCD were identified. Most patients with CD and pCD were men (79.3%). The mean age at CD diagnosis was lower in patients with pCD (33.7 years) than in those without pCD (44.9 years). Approximately half the patients with pCD received the pCD diagnosis at least 6 months before receiving a CD diagnosis. Approximately one-third (121/358) of patients with pCD had recurrent fistula; the median recurrence interval was 239 days. Compared with patients without pCD, patients with pCD had higher mean incidences of hospitalization (7.0 vs 3.8, P < .01), outpatient visits (13 vs 2.9, P < .01), and emergency room visits (10.3 vs 4.4, P < .01) over a 15-year period. Although patients with pCD had higher rates of healthcare utilization, their 15-year mortality rate was lower than that of those without pCD (6.1% vs 17.3%, P < .01).

Conclusions

The period prevalence of pCD in Taiwanese patients with CD was 14.8%. Although patients with pCD required more intensive care and had greater healthcare utilization, they did not have inferior survival outcomes compared with those without pCD.

Long-term Outcomes of Perianal Fistulas in Pediatric Crohn's Disease

BACKGROUND

Approximately 30% of Crohn's disease-related perianal fistulas heal in the adult population with conventional medical and surgical interventions. This healing rate remains unknown in pediatric patients.

OBJECTIVE

This study aimed to determine the healing rate of pediatric perianal Crohn's fistulas and identify factors associated with healing.

DESIGN

Retrospective case series.

SETTING

A quaternary referral center.

PATIENTS

Patients aged <18 years with a Crohn's perianal fistula, seen between January 1, 1991, and August 1, 2021, were included in the study.

INTERVENTIONS

Multivariable logistic regression to identify factors independently associated with perianal fistula healing.

MAIN OUTCOME MEASURES

Healing of Crohn's perianal fistula at the date of last clinical encounter, defined as the clinical note reporting a healed fistula or normal perianal examination.

RESULTS

A total of 91 patients aged <18 years with a Crohn's disease-related perianal fistula were identified (59% female, 76% white). The mean (SD) age at Crohn's diagnosis was 12 (±4) years. The mean follow-up after Crohn's diagnosis was 10 (±7) years. Overall, 89% of patients had a perianal fistula, 2% had an anovaginal fistula, and 10% had an ileal pouch-associated fistula. Patients underwent a median (interquartile range) of 2 (1-5) operations. A seton was placed in 60% of patients, 47% underwent abscess drainage, and 44% underwent fistulotomy or fistulectomy. Fistula healing occurred in 71% of patients over a median of 1.3 (0.4-2.5) years. Seven patients (7%) underwent proctectomy, and 3 (3%) underwent ileal pouch excision. After multivariable adjustment, younger age at diagnosis of perianal fistula was associated with an increased likelihood of healing (OR 0.56 for each increased year; 95% CI, 0.34-0.92).

LIMITATIONS

Retrospective, single institution.

CONCLUSIONS

Over two-thirds of fistulas heal in pediatric Crohn's disease patients with conventional surgical and medical intervention. Younger age at fistula development is associated with an increased likelihood of healing. See Video Abstract at http://links.lww.com/DCR/C185 .

RESULTADOS A LARGO PLAZO DE LAS FSTULAS PERIANALES EN LA ENFERMEDAD DE CROHN EN PACIENTES PEDITRICOS

ANTECEDENTES:Aproximadamente el 30% de las fístulas perianales relacionadas con la enfermedad de Crohn se curan en la población adulta con intervenciones médicas y quirúrgicas convencionales. Esta tasa de curación sigue siendo desconocida en pacientes pediátricos.OBJETIVO:Determinar la tasa de curación de las fístulas de Crohn perianales en población pediátrica e identificar los factores asociados con la curación.DISEÑO:Serie de casos retrospectiva.ESCENARIO:Un centro de referencia cuaternario.PACIENTES:Pacientes menores de 18 años con fístula(s) perianal(es) por enfermedad de Crohn, atendidos entre el 1 de enero de 1991 y el 1 de agosto de 2021.INTERVENCIONES:Regresión logística multivariable para identificar factores asociados de forma independiente con la cicatrización de la fístula perianal.PRINCIPALES MEDIDAS DE RESULTADO:Curación de la fístula perianal de Crohn en la fecha del último encuentro clínico, definida como la nota clínica que informa una fístula curada o un examen perianal normal.RESULTADOS:Se identificó un total de 91 pacientes <18 años de edad con una fístula perianal relacionada con la enfermedad de Crohn (59% mujeres, 76% blancos). La edad media (DE) al diagnóstico de Crohn fue de 12 (±4) años. El seguimiento medio tras el diagnóstico de Crohn fue de 10 (±7) años. En general, el 89 % de los pacientes tenía fístula perianal, el 2 % tenía fístula anovaginal y el 10 % de los pacientes tenía fístula asociada a reservorio ileal. Los pacientes fueron sometidos a una mediana (RIC) de 2 (1-5) operaciones. En el 60% de los pacientes se colocó sedal, en el 47% se drenó el absceso y en el 44% se realizó fistulotomía o fistulectomía. La curación de la fístula se produjo en el 71% de los pacientes durante una mediana de 1,3 (0,4-2,5) años. Siete pacientes (7%) se sometieron a proctectomía y 3 (3%) se sometieron a escisión del reservorio ileal. Después del ajuste multivariable, la edad más joven en el momento del diagnóstico de la fístula perianal se asoció con una mayor probabilidad de curación (OR 0,56 por cada año de aumento, IC del 95%, 0,34-0,92).LIMITACIONES:Retrospectivo, institución única.CONCLUSIONES:Más de dos tercios de las fístulas se curan en pacientes pediátricos con enfermedad de Crohn con intervención médica y quirúrgica convencional. Una edad más joven en el momento del desarrollo de la fístula se asocia con una mayor probabilidad de curación. Consulte Video Resumen en http://links.lww.com/DCR/C185 . (Traducción--Dr. Felipe Bellolio ).

Crohn's Disease-Associated and Cryptoglandular Fistulas: Differences and Similarities

Perianal fistulas are defined as pathological connections between the anorectal canal and the perianal skin. Most perianal fistulas are cryptoglandular fistulas, which are thought to originate from infected anal glands. The remainder of the fistulas mainly arises as complications of Crohn's disease (CD), trauma, or as a result of malignancies. Fistulas in CD are considered as a consequence of a chronic and transmural inflammatory process in the distal bowel and can, in some cases, even precede the diagnosis of CD. Although both cryptoglandular and CD-associated fistulas might look similar macroscopically, they differ considerably in their complexity, treatment options, and healing rate. Therefore, it is of crucial importance to differentiate between these two types of fistulas. In this review, the differences between CD-associated and cryptoglandular perianal fistulas in epidemiology, pathogenesis, and clinical management are discussed. Finally, a flow chart is provided for physicians to guide them when dealing with patients displaying their first episode of perianal fistulas.

ASSESSMENT OF RISK FACTORS FOR SURGERY TREATMENT OF CROHN'S DISEASE: A HOSPITAL COHORT

BACKGROUND

New therapies have revolutionized the treatment of Crohn's disease (CD), but in some countries, the surgery rate has not changed, the frequency of emergency surgery is underestimated, and surgical risk is poorly studied.

AIMS

The aim of this study was to identify risk factors and clinical indications for primary surgery in CD patients at the tertiary hospital.

METHODS

This was a retrospective cohort of a prospectively collected database of 107 patients with CD from 2015 to 2021. The main outcomes were the incidence of surgery treatment, types of procedures performed, surgical recurrence, surgery free time, and risk factors for surgery.

RESULTS

Surgical intervention was performed in 54.2% of the patients, and most of the procedures were emergency surgeries (68.9%). The elective procedures (31.1%) were performed over 11 years after diagnosis. The main indications for surgery were ileal stricture (34.5%) and anorectal fistulas (20.7%). The most frequent procedure was enterectomy (24.1%). Recurrence surgery was most common in emergency procedures (OR 2.1; 95%CI 1.6-6.6). Montreal phenotype L1 stricture behavior (RR 1.3; 95%CI 1.0-1.8, p=0.04) and perianal disease (RR 1.43; 95%CI 1.2-1.7) increased the risk of emergency surgeries. The multiple linear regression showed age at diagnosis as a risk factor for surgery (p=0.004). The study of surgery free time showed no difference in the Kaplan-Meier curve for Montreal classification (p=0.73).

CONCLUSIONS

The risk factors for operative intervention were strictures in ileal and jejunal diseases, age at diagnosis, perianal disease, and emergency indications.

Can we change the natural course of inflammatory bowel disease?

Inflammatory bowel diseases (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), are lifelong diseases characterized by chronic inflammation of the gastrointestinal tract leading to its progressive and irreversible destruction. Whether early initiation of IBD-specific therapy impacts the long-term course of the disease remains unclear and has to be further explored in prospective disease-modification trials. Historically, surgery and hospitalization rates have been the surrogate markers to measure disease progression in IBD, providing an overview of the effectiveness of medical therapies. However, neither surgery nor hospitalization necessarily reflects a fail in therapeutic medical management, and many confounding factors make them biased outcomes. The Selecting Endpoints for Disease-Modification Trials consensus has defined the disease-modification endpoints required for these trials, including the impact of the disease on patient's life (health-related quality of life, disability, and fecal incontinence), the mid-term disease complications (bowel damage in CD, IBD-related surgery and hospitalizations, disease extension in UC, extra-intestinal manifestations, permanent stoma, short bowel syndrome), and the development of dysplasia/cancer and mortality in the long term. Most available data in the literature regarding the impact of current therapies on disease progression focused on anti-tumor necrosis factor agents and are based on retrospective or post-hoc studies. Thus, prospective disease-modification trials are pressingly required to explore the effectiveness of early intensified treatment in patients with severe disease or at risk for disease progression.

Hypoxia-Inducible Factor 1-Alpha Stabilizers in the Treatment of Inflammatory Bowel Diseases: Oxygen as a Novel IBD Therapy?

Despite the significant advances in the medical armamentarium for inflammatory bowel diseases [IBD], current treatment options have notable limitations. Durable remission rates remain low, loss of response is common, administration routes are largely parenteral for novel biologics, and medication safety remains a concern. This explains an ongoing unmet need for safe medications with novel mechanisms of action that are administered orally. In line with these criteria, hypoxia-inducible factor [HIF]-1α stabilizers, acting via inhibition of prolyl hydroxylase enzymes, are emerging as an innovative therapeutic strategy. We herein review the mechanism of action and available clinical data for HIF-1α stabilizers and their potential place in the future IBD treatment algorithm.

Predictors of Perianal Fistula Healing in Children With Newly Diagnosed Crohn Disease

OBJECTIVES

Perianal fistulas are among the most severe complications of Crohn disease, but limited data regarding their outcomes are available in children. Our objective was to determine predictors of perianal fistula healing among pediatric patients newly diagnosed with Crohn disease.

METHODS

This single-center retrospective study followed patients with perianal fistulas at Crohn disease diagnosis until fistula healing. Time to healing was analyzed using Cox proportional hazard regression models considering relevant covariates including patient demographics, disease characteristics, medical therapies [no anti-tumor necrosis factor (TNF)α therapy, anti-TNFα therapy ±therapeutic drug monitoring], and perianal surgical procedures including fistulotomy, fistulectomy, removal of perianal lesions, seton placement, and incision and drainage.

RESULTS

Of 485 patients identified, 107 (22%) had a perianal fistula at Crohn disease diagnosis. Multivariate analysis identified that perianal fistulotomy, fistulectomy, and lesion removal [hazard ratio (HR) 0.46; P = 0.028], non-White race (HR 0.30, P < 0.01), and male sex (HR 0.42; P = 0.02) were associated with delayed fistula healing. Faster fistula healing was associated with treatment with anti-TNFα with therapeutic drug monitoring (HR 1.78, P = 0.009). There were no other differences in healing by treatment.

CONCLUSIONS

Fistulotomy, fistulectomy, and perianal lesion removal as well as non-White race were associated with delayed fistula healing. Anti-TNFα therapy was associated with faster fistula healing when combined with therapeutic drug monitoring, compared to all other medical treatment groups, including anti-TNFα therapy without therapeutic drug monitoring.

Endoscopic Evaluation and Management of Perianal Disease

Perianal Crohn's disease is associated with decreased quality of life, high morbidity, and high health care use. Treatment goals are to provide infection control, stop fistula drainage, and heal fistula tracts while preserving the anorectal sphincter. Treatment includes a combination of medical and surgical intervention, but new techniques are using interventional endoscopy to act as either a bridge to surgery or to decrease the need for surgical intervention. The decision on which approach to pursue requires knowledge of prior surgery, altered anatomy, prior fistula treatment, and imaging and endoscopic evaluation of fistula complexity, mucosal involvement, and associated stricture or abscess.

Crohn's Disease with Fistula: 10 Year Trends and Mortality in the United States

BACKGROUND/AIMS

Crohn's disease (CD) results in significant morbidity, mortality, and healthcare burden. This study evaluated the temporal trends of CD hospitalizations with a fistula over the last decade to understand the outcomes of severe CD.

METHODS

National Inpatient Sample database from 2009 to 2019 was used to identify CD hospitalizations with a fistula. The outcomes of interest included temporal trend analysis of length of stay (LOS), mean inpatient cost (MIC), and mortality.

RESULTS

There was an increase in the total number of fistulizing CD hospitalizations from 5,386 in 2009 to 12,900 in 2019 (p<0.01). The mean age decreased from 44.9±0.6 to 41.8±0.4 years for the study period (p<0.01). Caucasians were the predominant ethnicity, followed by Africans, Hispanics, and others (p<0.001). The mean LOS for fistulizing CD hospitalizations decreased significantly from 11.57±0.09 days in 2009 to 7.20±0.05 days in 2019 (p<0.001). There was a significant decrease in inpatient mortality from 1.72% in 2009 to 0.73% in 2019 (p<0.01). The MIC did not have a significant trend. There was a decreasing trend toward partial/total colectomies, rectosigmoid, and small bowel surgeries from 2009 to 2019 (p<0.001).

CONCLUSIONS

There has been a rise in CD hospitalizations with fistulizing disease in the last decade. Despite this, the mortality and inpatient LOS have been decreasing significantly. In addition, the increase in CD hospitalizations with fistulizing disease has had no significant effect on hospital costs.

Perianal Crohn's disease and the development of colorectal and anal cancer: A systematic review and meta-analysis

BACKGROUND AND AIMS

The aim of this systematic review was to assess the literature on the incidence and risk factors for colorectal cancer and anal cancer in patients with perianal Crohn's disease.

METHOD

A systematic review of the literature was performed using PubMed, Embase and Google Scholar. A meta-analysis was then conducted using a random-effect model.

RESULTS

Five studies were included in the systematic review. Out of all patients, 26.5% had perianal Crohn's Disease. The median follow-up was six years. In total, 127 cases of colorectal cancer were found (0.43% of the included Crohn's disease patients). Perianal involvement was present in 50% of colorectal cancer patients (0.89% of the population). Three of the studies specified the cancer to be rectal or anal, which were present in 68 and 24 cases (0.3% and 0.1% of patients), respectively. In a subgroup analysis of rectal- and anal cancer, perianal involvement was most frequent in anal cancer, accounting for 46% of the cases. In the rectal cancer group, 37% had perianal involvement. The higher incidence of colorectal cancer in patients with perianal Crohn's was confirmed in a meta-analysis.

CONCLUSION

Half of patients with colorectal cancer and anal cancer were found to have perianal Crohn's. In patients with perianal involvement, there was a higher percentage of anal cancer compared with rectal cancer. These results support the theory that patients with perianal Crohn's are at increased risk for developing colorectal- and anal cancer. Studies, collecting more detailed data about patients and their cancers, are necessary to further specify the disease course.

Examination Under Anesthesia May Not Be Universally Required Prior to Anti-TNF Therapy in Perianal Crohn's Disease: A Comparative Cohort Study

BACKGROUND

Multidisciplinary care involving exam under anesthesia (EUA) and tumor necrosis factor (TNF) inhibitors is recommended for perianal Crohn's disease. However, the impact of this combined approach is not well established.

METHODS

We performed a comparative cohort study between 2009 and 2019. Patients with perianal Crohn's disease treated with EUA before anti-TNF therapy (combined modality therapy) were compared with anti-TNF alone. The primary outcome was fistula closure assessed clinically. Secondary outcomes included subsequent local surgery and fecal diversion. Multivariable analysis adjusted for abscesses, concomitant immunomodulators, and time to anti-TNF initiation was performed.

RESULTS

Anti-TNF treatment was initiated 188 times in 155 distinct patients: 66 (35%) after EUA. Abscesses (50% vs 15%; P < .001) and concomitant immunomodulators (64% vs 50%; P = .07) were more common in the combined modality group, while age, smoking status, disease duration, and intestinal disease location were not significantly different. Combined modality therapy was not associated with higher rates of fistula closure at 3 (adjusted odds ratio [aOR], 0.7; 95% confidence interval [CI], 0.3-1.8), 6 (aOR, 0.8; 95% CI, 0.4-2.0) and 12 (aOR, 1.0; 95% CI, 0.4-2.2) months. After a median follow-up of 4.6 (interquartile range, 5.95; 2.23-8.18) years, combined therapy was associated with subsequent local surgical intervention (adjusted hazard ratio, 2.2; 95% CI, 1.3-3.6) but not with fecal diversion (adjusted hazard ratio, 1.3; 95% CI, 0.45-3.9). Results remained consistent when excluding patients with abscesses and prior biologic failure.

CONCLUSIONS

EUA before anti-TNF therapy was not associated with improved clinical outcomes compared with anti-TNF therapy alone, suggesting that EUA may not be universally required. Future prospective studies controlling for fistula severity are warranted.

Treatment of Fistulizing Perianal Crohn's Disease by Autologous Microfat Enriched With Adipose-Derived Regenerative Cells

In this pilot study, short-term efficacy and safety of fat graft enriched with Adipose-Derived Regenerative Cells (ADRC) in the treatment of Crohn’s high anal fistula was evaluated. Clinical fistula healing was achievable in 75% of cases, by a single treatment.

Health Care Costs and Resource Utilization Among Patients With Crohn's Disease With and Without Perianal Fistula

BACKGROUND

Perianal fistula (PAF), a complication of Crohn's disease (CD), is associated with substantial economic costs and poor prognosis. We determined prevalence of PAF CD in the United States and compared costs and health care resource utilization (HRU) of PAF CD patients with matched non-PAF CD patients.

METHODS

This was a retrospective cohort study of claims data from the IBM MarketScan Commercial Database from October 1, 2015, to September 30, 2018. Eligible patients were aged 18 to 89 years with ≥2 CD diagnoses. Patients with PAF CD had ≥1 PAF diagnosis or procedure code and were matched with non-PAF CD patients. Cumulative prevalence of PAF CD in the US population was calculated across total patients in MarketScan. All-cause and gastrointestinal (GI)-related costs and HRU were compared between groups using a generalized linear model (GLM).

RESULTS

Cumulative 3-year prevalence of PAF was 7.70% of patients with CD (N = 81,862) and 0.01% of the US population. Among PAF CD (n = 1218) and matched non-PAF CD (n = 4095) patients, most all-cause costs and HRU were GI-related. Mean total all-cause and GI-related health care costs per patient and per year for PAF CD were $85,233 and $71,612, respectively, vs $40,526 and $29,458 for non-PAF CD (P < .0001). Among PAF CD vs non-PAF CD patients, GLM-adjusted proportions of patients with GI-related inpatient, outpatient, or pharmacy visits, mean GI-related inpatient length of stay, and mean GI-related surgeries were higher (P < .0001 for all comparisons).

CONCLUSIONS

Costs and HRU are significantly higher for patients with PAF CD vs non-PAF CD patients, highlighting the economic burden of the disease.

Perianal Imaging in Crohn Disease: Current Status With a Focus on MRI, From the AJR Special Series on Imaging of Inflammation

Fistulizing perianal disease, a frequent, chronic, and often debilitating manifestation of Crohn disease (CD) in adults and children, has been relatively refractory to treatment in the past. The advent of biologic agents such as anti-tumor necrosis factor-α and cellular therapies, used in conjunction with a range of surgical interventions, has greatly improved disease outcomes, although complete remission can still be elusive. This Special Series review considers current perianal imaging options, specifically pelvic MRI and endoanal and transperineal ultrasound, as well as their roles in the diagnosis, management, and assessment of treatment response. Pelvic MRI is the first-line modality for imaging perianal CD, given the complexity of fistulas encountered in CD. MRI technical acquisition parameters for adults and children and an approach to MRI interpretation and reporting are provided. Anatomic classification systems for fistulizing peri-anal disease are presented. We also explore the history, current landscape, and future developments of MRI features of perianal disease as imaging biomarkers, to quantify activity and severity and to consider CD MRI-based inflammatory activity scores. We discuss the reliability and validation of a number of indexes (including the pediatric MRI-based perianal CD [PEMPAC] index, the MR novel index for fistula imaging in CD [MAGNIFI-CD], the Van Assche index, and the modified Van Assche index), their potential to quantify treatment response, and possible prognostic capabilities.

Direct health care costs of managing perianal Crohn's Disease in a population based cohort

BACKGROUND

Crohn's disease is a chronic condition that places a high health care cost burden. Perianal Crohn's disease (pCD) is a difficult phenotype to treat due to poorer response to medical and surgical therapies. No study has assessed if this translates to higher healthcare costs. The aim is to assess the cost of treating pCD and compare to the cost of non-perianal Crohn's disease (CD).

METHODS

This is a retrospective case-control cohort study in a population-based setting. The direct healthcare costs for patients with pCD were calculated over 12 months. Data was compared to the control group of non-perianal CD patients on biologic treatment, with the use of the Mann-Whitney rank test to assess significance.

RESULTS

187 Crohn's patients were included (39 pCD, 148 CD). Per patient, annual cost was €17,779.19 and €17,576.86 respectively (p = .9391). Medications were responsible for the majority of cost at 78% and 92% of total cost in pCD and CD, respectively (€13,886.04 in pCD, and €16,007.10 in CD), of which biologics were the main driver. Surgical costs were higher in the pCD group due to a higher cost of luminal surgery (€2633.88 in pCD vs €209.79 in CD, p = .0270).

CONCLUSION

This is the first study to assess the cost of treating perianal Crohn's disease in a real-world population. Although the costs were similar overall to non-perianal Crohn's patients, the perianal cohort had higher surgical costs from luminal surgery. This demonstrates the potential to apply early intensive treatment to reduce future surgical cost.

Choosing the right biologic for complications of inflammatory bowel disease

INTRODUCTION

Inflammatory bowel disease (IBD) is a chronic, inflammatory condition that involves the intestinal tract, and can also present with extra-intestinal manifestations (EIM). Choosing the right treatment for IBD is often nuanced and decisions can become even more complicated when a patient presents with or develops a complication of the disease.

AREAS COVERED

We aimed to provide an overview of the most common complications of IBD, specifically intestinal and EIM, and summarize the data regarding biologic therapy for treatment of these conditions. A comprehensive literature review was performed using PubMed and Medline databases to identify studies published in the English language relevant to the broad scope of this review.

EXPERT OPINION

There are still significant gaps in our understanding of the pathophysiology of IBD and its treatment, especially in regards to complications of the disease. As novel therapies continue to emerge for treatment of IBD, we feel concurrent examination of their impact on intestinal complications and EIM of IBD is important and should be a priority of future research.

Natural History of Perianal Crohn's Disease: Long-term Follow-up of a Population-Based Cohort

BACKGROUND AND AIMS

The natural history of perianal Crohn's disease (PCD) remains poorly described and is mainly based on retrospective studies from referral centers. The aim of this study was to assess the incidence, outcomes and predictors of the onset of PCD.

METHODS

All incident cases of patients diagnosed with possible CD were prospectively registered from 1994 to 1997 in Brittany, a limited area in France. At diagnosis, the clinical features of perianal disease were recorded. All patient charts were reviewed from the diagnosis to the last clinic visit in 2015.

RESULTS

Among the 272 out of 331 incident CD patients followed up, 51 (18.7%) patients had PCD at diagnosis. After a mean follow-up of 12.8 years, 93 (34%) patients developed PCD. The cumulative probabilities of perianal CD occurrence were 22%, 29%, and 32% after 1 year, 5 years, and 10 years, respectively. The cumulative probabilities of anal ulceration were 14%, and 19% after 1 year and 10 years, respectively. Extraintestinal manifestations were associated with the occurrence of anal ulceration. The cumulative probabilities of fistulizing PCD were 11%, 16%, and 19% after 1 year, 5 years, and 10 years, respectively. Extraintestinal manifestations, rectal involvement and anal ulceration were predictors of fistulizing PCD. The cumulative probability of developing anal stricture was 4% after 10 years.

CONCLUSIONS

PCD is frequently observed during CD, in approximately one-third of patients. These data underline the need for targeted therapeutic research on primary perianal lesions (proctitis, anal ulceration) to avoid the onset of fistulizing perianal disease.

Surgical closure, mainly with glue injection and anti-tumour necrosis factor α, in fistulizing perianal Crohn's disease: A multicentre randomized controlled trial

AIM

In patients with fistulizing perianal Crohn's disease (CD), the need for a secondary surgical step is not defined. The aim was to assess the efficacy of surgical closure compared to a single seton removal in patients with drained fistulizing perianal CD treated with adalimumab.

METHODS

This was a multicentre, randomized controlled trial, comparing seton removal + surgical closure (closure group) to seton removal alone (control group) with a stratification according to the American Gastroenterological Association classification. The primary end-point was fistula closure at month 12 defined by the association of the following criteria: no seton, absence of a visible external opening, absence of discharge from the tract after finger compression, absence of an internal opening, absence of perianal pain/abscess and absence of fistula-related abnormalities.

RESULTS

Among the 64 included patients (262 expected) (48 complex fistula, 75%), 33 were randomized to the closure group and 31 to the control group. In the closure group, 26 patients (78.8%) had glue. At month 12, overall fistula closure was achieved in 35 of the evaluable 58 patients (60%): 18/32 (56%) in the surgery group and 17/26 (65%) in the control group (P = 0.479). In the closure group, fistula closure was observed in 13/25 (52%) and 5/7 (71%) patients with complex and simple fistula respectively (P = 0.426), compared with 12/18 (67%) and 5/8 (63%), respectively in the control group (P = 1.000).

CONCLUSIONS

Seton removal alone seems to be no more effective than a secondary surgical step (in particular glue injection) in patients having fistulizing perianal CD controlled by an initial drainage combined with adalimumab. The results should be interpreted with caution.

Fecal Diversion for Perianal Crohn Disease in the Era of Biologic Therapies: A Multicenter Study

BACKGROUND

The natural history of perianal Crohn disease (PCD) after fecal diversion in the era of biologics is poorly understood. We assessed clinical and surgical outcomes after fecal diversion for medically refractory PCD and determined the impact of biologics.

METHODS

We performed a retrospective, multicenter study from 1999 to 2020. Patients who underwent fecal diversion for refractory PCD were stratified by diversion type (ostomy with or without proctectomy). Times to clinical and surgical outcomes were estimated using Kaplan-Meier methods, and the association with biologics was assessed using multivariable Cox proportional hazards models.

RESULTS

Eighty-two patients, from 3 academic institutions, underwent a total of 97 fecal diversions: 68 diversions without proctectomy and 29 diversions with proctectomy. Perianal healing occurred more commonly after diversion with proctectomy than after diversion without proctectomy (83% vs 53%; P = 0.021). Among the patients who had 68 diversions without proctectomy, with a median follow-up of 4.9 years post-diversion (interquartile range, 1.66-10.19), 37% had sustained healing, 31% underwent surgery to restore bowel continuity, and 22% underwent proctectomy. Ostomy-free survival occurred in 21% of patients. Biologics were independently associated with avoidance of proctectomy (hazard ratio, 0.32; 95% confidence interval, 0.11-0.98) and surgery to restore bowel continuity (hazard ratio, 3.10; 95% confidence interval, 1.02-9.37), but not fistula healing.

CONCLUSIONS

In this multicenter study, biologics were associated with bowel restoration and avoidance of proctectomy after fecal diversion without proctectomy for PCD; however, a minority of patients achieved sustained fistula healing after initial fecal diversion or after bowel restoration. These results highlight the refractory nature of PCD.

A systematic review of the patient burden of Crohn’s disease-related rectovaginal and anovaginal fistulas

Background

Crohn’s disease (CD)-related rectovaginal fistulas (RVFs) and anovaginal fistulas (AVFs) are rare, debilitating conditions that present a substantial disease and treatment burden for women. This systematic literature review (SLR) assessed the burden of Crohn’s-related RVF and AVF, summarizing evidence from observational studies and highlighting knowledge gaps.

Methods

This SLR identified articles in PubMed and Embase that provide data and insight into the patient experience and disease burden of Crohn’s-related RVF and AVF. Two trained reviewers used pre-specified eligibility criteria to identify studies for inclusion and evaluate risk of bias using the Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I) tool for observational studies.

Results

Of the 582 records identified, 316 full-text articles were assessed, and 16 studies met a priori eligibility criteria and were included. Few epidemiology studies were identified, with one study estimating the prevalence of RVF to be 2.3% in females with Crohn’s disease. Seven of 12 treatment pattern studies reported that patients had or required additional procedures before and/or after the intervention of interest, demonstrating a substantial treatment burden. Seven of 11 studies assessing clinical outcomes reported fistula healing rates between 50 and 75%, with varying estimates based on population and intervention.

Conclusions

This SLR reports the high disease and treatment burden of Crohn’s-related RVF and AVF and identifies multiple evidence gaps in this field. The literature lacks robust, generalizable data, and demonstrates a compelling need for substantial, novel research into these rare and debilitating sequelae of CD.

Registration The PROSPERO registration number for the protocol for this systematic literature review is CRD42020177732.

A Multi-Disciplinary Approach to Perianal Fistulizing Crohn's Disease

Perianal fistulizing Crohn's disease represents a severe phenotype associated with significant morbidity. Patients with perianal fistulizing disease are more likely to have a severe disease course and have significant reductions in quality of life. Moreover, these patients are at risk for the development of distal rectal and anal cancers. Given the complexity and severity of this patient group, the management of perianal Crohn's disease must be undertaken by a multidisciplinary team. The gastroenterologist and colorectal surgeon play a critical role in the diagnosis and management of perianal fistulizing disease. An examination under anesthesia provides critical information and is an essential part of the work-up of complex perianal fistulas. The radiologist also plays a central role in characterizing anatomy and assessing response to treatment. Several imaging modalities are available for these patients with magnetic resonance imaging as the imaging modality of choice. Perianal disease developing after ileal pouch-anal anastomosis represents a particularly challenging form of fistulizing disease and requires a multidisciplinary clinical and radiologic approach to differentiate surgical complications from recurrent Crohn's disease.