Perianal Disease Activity Index Research Articles

A phase I/II clinical trial of ex-vivo expanded human bone marrow derived allogeneic mesenchymal stromal cells in adult patients with perianal fistulizing Crohn’s Disease

BackgroundPerianal fistulas (PF) affect one-third patients with Crohn’s disease (CD) with limited therapeutic options. There is dearth of literature on safety and efficacy of bone marrow-derived mesenchymal stromal cells (BMSCs) in this population.MethodsAn open-label, phase I/II, single-arm study was conducted involving local administration of human allogeneic bone marrow-derived mesenchymal stromal cells in perianal fistula of patients with Crohn’s disease refractory to standard therapies. Clinical severity and biomarkers were assessed at baseline and periodically until week 104 , and MRI at week 24 and 104. Primary and secondary objectives were to assess safety and efficacy respectively. Fistula remission was complete closure of fistula openings with < 2 cm perianal collection on MRI, and fistula response was decrease in drainage by ≥ 50%. Change in perianal disease activity index, quality-of-life and Van Assche index on MRI over time was assessed using mixed-effect linear regression model.ResultsTen patients (male:8, mean age:27.4 ± 12.0years) were recruited. Self-resolving procedure-related adverse events occurred in three patients, with no follow-up adverse events. In intention to treat analysis at week 24, two patients (20%) achieved fistula remission and seven (70%) had fistula response. At week 52, two (20%) patients were in remission and seven (70%) maintained response. At 104 weeks, two (20%) patients maintained response and one (10%) was in remission. Statistically significant decrease in perianal disease activity index (P = 0.008), Van Assche Index (P = 0.008) and improvement in quality-of-life (P = 0.001) were observed over time.ConclusionsAllogeneic BMSCs are safe and effective for the treatment of perianal fistulizing CD with significant improvement in clinical severity and radiological healing.Trial registrationThe study was prospectively registered on Clinical trials registry – India (CTRI), CTRI/2020/01/022743 on 14 January 2020, http://ctri.nic.in.

The development of a cryptoglandular anal fistula quality of life scale (AF-QoL).

Quality of life (QoL) is a crucial and core outcome in assessing the effectiveness of treatments for cryptoglandular anal fistula. Despite its extensive impact, there is a lack of patient-centred, disease-specific QoL measurement instruments of adequate quality. The aim of this study is to develop a disease-specific measurement instrument that can accurately measure QoL for patients with cryptoglandular anal fistula. Semi-structured qualitative patient interviews and a systematic review of current instruments were used to generate items for the draft instrument. This underwent successive rounds of cognitive interviews to refine its wording and structure. Individual item and overall scale content validity were determined by asking experts to rate the relevance of each item and those deemed irrelevant were removed. The final instrument then underwent psychometric testing and test-retest analysis to determine its sensitivity and stability. A total of 148 patients were involved in item generation, scale development and psychometric testing. A 22-item measurement instrument has been developed; it is scored on a scale of 0-100, where 0 indicates the worst QoL and 100 demonstrates perfect QoL. The scale demonstrates excellent internal consistency (Cronbach-α = 0.927), strong content and construct validity [correlation with Perianal Disease Activity Index = -0.713, Hospital Anxiety and Depression Anxiety (-0.659) and Depression (-0.673) subscales and Short Form-12 physical (0.609) and mental (0.589) component scales] and strong reliability and responsiveness. We have developed a cryptoglandular Anal Fistula Quality of Life scale (AF-QoL), a comprehensive, disease-specific patient reported outcome measure assessing QoL in patients with cryptoglandular anal fistula.

Monitoring-Based Model for Personalizing Fecal Incontinence in Patients With Crohn's Disease: A Multicenter Inception Cohort Study.

Fecal incontinence (FI) is a common complaint that greatly affects the quality of life of patients with Crohn's disease (CD) and is associated with the clinical characteristics of CD. We aimed to identify risk factors related to FI and construct a risk prediction model for FI in patients with CD. This retrospective study included 600 Chinese patients with CD from 4 IBD centers between June 2016 and October 2021. The patients were assigned to the training (n = 480) and testing cohorts (n = 120). Two nomograms were developed based on the logistic regression and Cox regression models to predict the risk factors for FI in patients with CD. The discriminatory ability and accuracy of the nomograms were evaluated using the receiver operating characteristic (ROC) curves and the area under the ROC curves (AUCs). Additionally, the Kaplan-Meier survival curve was also used further to validate the clinical efficacy of the Cox regression model. The overall prevalence of FI was 22.3% (n = 134 of 600). In the logistic regression model, age at diagnosis (odds ratio [OR], 1.032; P = .033), penetrating behavior of disease (OR, 3.529; P = .008) and Perianal Disease Activity Index score >4 (OR, 3.068; P < .001) were independent risk factors for FI. In the Cox regression model, age at diagnosis (hazard ratio [HR], 1.027; P = .018), Montreal P classification (HR, 2.608; P = .011), and Perianal Disease Activity Index score >4 (HR, 2.190; P = .001) were independent predictors of the prevalence of FI over time. Two nomograms were developed to facilitate risk score calculation, and they showed good discrimination ability according to AUCs. In this study, we identified 4 risk factors related to the prevalence of FI and developed 2 models to effectively predict the risk scores of FI in CD patients, helping to delay the course of FI and improve the prognosis with timely intervention.

P700 The efficacy of adalimumab combined with surgery for rectovaginal fistula in Crohn's disease：a single-center retrospective study

Abstract Background To assess the efficacy of adalimumab(ADA)combined with surgery in the treatment of Crohn's disease patients with rectovaginal fistulas. Methods A single-center retrospective study. The baseline data of patients with Crohn’s rectovaginal fistulas who visited the Anorectal Department of the Affiliated Hospital of Nanjing University of Chinese Medicine from January 2020 to July 2022 and accepted ADA combined with surgery treatment were included. Crohn’s disease Activity Index(CDAI), perianal disease activity index(PDAI) and inflammatory parameters, including Erythrocyte sedimentation rate(ESR) and C-reactive protein(CRP), were statistically analyzed at weeks0, 48. Follow-up was performed every 8 weeks. The outcomes included clinical response, clinical remission, fistula response, fistula remission, fistula remission under MRI, endoscopic response and endoscopic remission. Results A total of 43 RVF patients were included, 53.4% (23/43) patients were treated with Seton,44.1% (19/43) patients were treated with Advancement flap and 2.3%(1/43) patient was treated with Fecal diversion, with a median follow-up of 11.0 (2.5-15.0) months. After 48 weeks of treatment, CDAI[325(262,397)vs.197(134,396)], PDAI[8(6,9) vs. 5(3,6)], ESR[31(8,50) mm/h vs. 10(4,28)mm/h]and CRP[4.62(0.85, 14.45)mg/L vs.0.5(0.5,2.14)mg/L] were significantly lower than 0 week (Table 1) . CDAI, PDAI, ESR and CRP at the 48th week of treatment were significantly lower than those before treatment (p&amp;lt;0.05). At the last follow-up, 62.7%(27/43) patients achieved clinical response, 30.2%(13/43) achieved clinical remission. Meanwhile 69.7%(30/43) of patients achieved fistula response,32.5%(14/43) achieved fistula remission(Table 2),and 25.5%(11/43) achieved fistula remission under MRI; A total of 37 patients completed endoscopic re-examination, including 54.0% (20/37) of patients with endoscopic response and 24.3%(9/37) with endoscopic remission. Conclusion ADA combined with surgery is effective in the treatment of patients with Crohn’s rectovaginal fistulas.

P882 A Phase I/II clinical trial of ex-vivo expanded human bone marrow derived allogeneic mesenchymal stromal cells in adult patients with perianal fistulizing Crohn’s Disease

Abstract Background Perianal fistulas affect one-third patients with Crohn’s disease with limited therapeutic options. There is dearth of literature on safety and efficacy of bone marrow-derived mesenchymal stromal cells in this population. Methods An open-label, phase I/II, single-arm study was conducted involving local administration of human allogeneic bone marrow-derived mesenchymal stromal cells in perianal fistula of patients with Crohn’s disease refractory to standard therapies. Clinical severity and biomarkers were assessed at baseline and periodically till 104 weeks, and MRI at 24 and 104 weeks. Primary and secondary objectives were to assess safety and efficacy respectively. Fistula remission was complete closure of fistula openings with &amp;lt;2cm perianal collection on MRI, and fistula response was decrease in drainage by ≥50%. Change in perianal disease activity index, quality-of-life and Van Assche index on MRI over time was assessed using mixed-effect linear regression model. Results Ten patients (male:8, mean age:27.4±12.0years) were recruited. Self-resolving procedure-related adverse events occurred in three patients, with no follow-up adverse events. In intention to treat analysis at week 24, two patients (20%) achieved fistula remission and seven (70%) had fistula response. At week 52, two (20%) patients were in remission and seven (70%) maintained response. At 104 weeks, two (20%) patients maintained response and one (10%) was in remission. Statistically significant decrease in perianal disease activity index(P=0.008), Van Assche Index(P=0.008) and improvement in quality-of-life(P=0.001) were observed over time. Conclusion Allogeneic BMSCs are safe and effective for the treatment of PF in CD with significant improvement in clinical severity and radiological healing.

DOP77 Mesenchymal stem cell therapy for refractory Crohn’s perianal fistulas: a case series

Abstract Background Nearly one-third of patients with Crohn’s disease will develop one or multiple perianal fistulas within the first two decades after diagnosis, with the majority being complex. Treatment options are limited with high recurrence rates after both medical and surgical approaches. It has been demonstrated that a completely fibrotic tract on Magnetic Resonance Imaging (MRI) with a MAGNIFI-CD &amp;lt;6 is the best predictor for long-term clinical closure. Mesenchymal stem cell treatment (MST) has emerged as a new therapeutic strategy for these fistulas. The aim of the current study was to analyse the effectiveness of MST for complex Crohn’s perianal fistulas based on MRI. Methods Consecutive patients with complex Crohn’s perianal fistulas, previously failing both anti-TNF treatment and surgical closure, that underwent surgical closure of the internal opening with MST between December 2019 and March 2023 were included. All patients underwent a MRI preoperatively and between three to six months after MST. For the current study, MRI’s were read by an senior radiologist. The primary endpoint was radiological remission of the fistula(s) defined as a MAGNIFI-CD &amp;lt;6 on MRI. Secondary endpoints were clinical closure (defined as closure of the external opening(s)), recurrence rate, change of MAGNIFI-CD over time, quality of life based on the perianal disease activity index (PDAI), and serious adverse events (SAE). Results In total, 30 patients (16 females) with 48 fistula tracts were included with a median clinical follow-up of 20 months. Radiological remission was achieved in thirteen patients (43.3%) after a median follow-up of 5.0 months (IQR 3.0-6.0). The median MAGNIFI-CD at baseline was 15.0 (IQR 7.0-20.0) which decreased significantly to 8.0 (IQR 3.0-15.0) after treatment (p= 0.001). Clinical closure of the fistula(s) was achieved in 21 patients (70.0%). Three patients (14.3%) developed a recurrence during long-term FU. All three patients had clinically closed fistula(s), but no radiological remission. The median PDAI decreased significantly from 10.5 (IQR 7.0-14.0) to 4.0 (IQR 0.0-7.3) (p= 0.001). Overall, in this patient group one SAE occurred requiring multiple reinterventions and temporary stoma. Conclusion Closure of the internal fistula opening with MST is a promising treatment strategy for therapy refractory Crohn’s perianal fistulas, resulting in &amp;gt;40% radiological remission and clinical closure in 70%. No recurrences were seen in patients with radiological remission. MST was also associated with a significant increase in quality of life. Further research is needed to gain insight in which patients MST is most likely to induce radiological remission.

P541 Long-term follow-up results of darvadstrocel for complex perianal fistulas in patients with Crohn's disease: 3-year outcomes from a Japanese phase 3 study

Abstract Background Darvadstrocel (DVS), a suspension of expanded human allogeneic mesenchymal stem cells extracted from adipose tissue, is for the treatment of complex perianal fistulas in patients with Crohn's disease (CD). In Japan, DVS was approved in 2021 based on the Japanese phase 3 study Week 52 data combined with the pivotal study ADMIRE-CD data. Patients who participated in the Japanese study were monitored for 3 years, and we report the results at Week (W) 156. Methods This was an open-label, uncontrolled, phase 3 study (converted to a post-marketing clinical study after approval) conducted from March 2019 to February 2023 in Japan. Subjects had complex Crohn’s perianal fistulas (CPF) refractory to conventional treatments with a maximum of 2 internal openings (IO) and 3 external openings (EO). The fistula tract was curetted approximately 2-3 weeks before DVS administration, and a drainage seton was placed. On the day of administration, seton was removed, fistula tracts were curetted again, and IO was sutured. A total of 24 mL of DVS (including 120x106 cells) was administered around the IO and into the wall of fistula tracts. During the 2-year follow-up period after W52, medical and surgical treatment for CD and CPF was given as needed, and subjects were assessed every 6 months. Results 22 Japanese patients were enrolled from 9 sites. The mean (SD) age was 36.4 (10.4) years, 63.6% were male, and the mean (SD) duration of CD was 11.3 (6.6) years. By W156, most frequently reported adverse events (AE) were anal fistula (7/22), proctalgia (7/22), and nasopharyngitis (6/22). New serious AE occurred after W52 were found in 9 subjects: COVID-19 (4), CD (2), perianal fistula, small bowel obstruction, premature labour (1 each). None of these were considered DVS-related. At W156, the combined remission rate (clinical and MRI assessment) was 15/22 (68.2%, 95% CI [48.7%, 87.6%]), clinical remission rate (clinical assessment) was 15/22 (68.2%, 95% CI [48.7%, 87.6%]), response rate (no drainage from ≥50% of treated EOs) was 20/22 (90.9%, 95% CI [78.9%, 100.0%]), and relapse rate (at least 1 relapse by W156 after achieving remission at W52) was 3/15 (20.0%, 95% CI [0.0%, 40.2%]). Mean Perianal Disease Activity Index (PDAI) total score (SD) was 4.8 (2.2) at baseline, which was decreased to 2.1 (2.1) at W52, and 1.7 (2.0) at W156. Mean Crohn's Disease Activity Index (CDAI) total score (SD) was 94.3 (60.1) on the day of administration, which was decreased to 73.7 (73.6) at W52, and 71.4 (51.2) at W156. Conclusion This is the first prospectively observed clinical outcomes in CPF for 3 years after DVS administration. There were no new safety findings, and fistula remission observed at W52 was maintained until W156.

P1086 Re-administration of infliximab in patients with extremely refractory perianal Crohn’s disease

Abstract Background This study aims to evaluate the efficacy of infliximab re-administration to a cohort of patients with extremely refractory perianal Crohn's Disease (CD). Methods Retrospective analysis of prospectively collected data in CD patients with perianal disease, who despite being treated with infliximab, had to change treatment either because of primary non-response, secondary loss of response, or due to the occurrence of an allergic reaction. They then became resistant to the other therapies tested, resulting in Infliximab being given again. We then evaluated the clinical response to fistula management (Perianal Disease Activity Index PDAI ≤ 4), as well as the occurrence of adverse reactions in these patients. Results We included 14 patients (8 women), with a mean age (SD) of 38.2 (9.5) years. According to the Montreal classification our patients had L1 (n=2), L2 (n=2) and L3 (n=10) disease. After the initial Infliximab failure (even after dose escalation), patients received vedolizumab, ustekinumab and adalimumab without response or with secondary loss of response. Therefore, it was decided to re-administer infliximab with concomitant administration of azathioprine. After 1 year of follow up clinical response (PDAI ≤ 4) was seen in 4 patients (28.5%). Re-administration of infliximab was discontinued in 2 patients due to severe allergic reaction; however, the remaining patients did not experience side effects. Conclusion Re-administration of Infliximab may be able to help a small percentage of treatment resistant patients with perianal CD.

DOP66 INSPIRE: Preliminary data from an observational post-marketing registry on the effectiveness and safety of darvadstrocel in patients with Crohn’s Disease and complex perianal fistulas

Abstract Background Darvadstrocel (DVS), a suspension of expanded allogeneic adipose-derived mesenchymal stem cells, is approved for the treatment of complex Crohn’s perianal fistulas (CPF). INSPIRE (EUPAS24267) is a European observational post-approval study evaluating real-world effectiveness and safety of DVS in patients with complex CPF for up to 36 months. Here we report preliminary clinical and safety outcomes from INSPIRE. Methods Patients with complex CPF who had received DVS according to local standard practice were eligible to enrol. Clinical response (closure of ≥50% of external openings [EOs]) and clinical remission (closure of all EOs) of DVS-treated fistulas that were draining at baseline, were evaluated in the all-treated (AT; received ≥1 dose of DVS with an evaluation for fistula response after 6 months) and per-protocol (PP; received DVS as per label-approved guidelines) cohorts. Treatment-emergent adverse events (TEAEs), serious TEAEs and AEs of special interest were reported for the safety cohort (all patients treated with DVS). Results As of April 2023, 652 patients had enrolled (Table 1). Complete data to evaluate 12-month clinical response and remission were available for 134 (AT cohort) and 124 (PP cohort) patients, of whom 79.9% (AT, n = 107) and 79.8% (PP, n = 99) had a clinical response and 76.1% (AT, n = 102) and 76.6% (PP, n = 95) had clinical remission (Figure 1). From baseline to Month 12, there was a decrease in the mean (standard deviation [SD]) Perianal Disease Activity Index score (–3.5 [3.3]; n/N = 96/302 and –3.7 [3.2]; n/N = 89/249) and a decrease in the mean (SD) Harvey–Bradshaw Index for Crohn’s disease activity (-0.3 [2.8]; n/N = 102/302 and -0.4 [2.9]; n/N = 95/249) in the AT and PP cohorts, respectively. Complete safety data were available for 619 patients (median [min–max] follow-up 480 [6–1595]) days. Overall, 26% (n = 162) had ≥1 TEAE and 10% (n = 63) ≥1 serious TEAE. The most frequent TEAEs were anal abscess (6.9%), COVID-19 (1.9%) and proctalgia (1.1%). No deaths were reported. One breast cancer lymph node metastasis and one ovarian epithelial cancer were reported; both events were confounded by immunosuppressant treatment and were not considered related to DVS treatment. Conclusion These preliminary data are consistent with the pivotal ADMIRE-CD study and demonstrate a single dose of DVS in patients with complex CPF is associated with positive clinical outcomes in up to 80% of patients, and a favourable safety profile, both of which are maintained after 12 months. The inherent limitations of registry-based studies mean these data should be interpreted with caution. However, the ongoing INSPIRE study will provide longer follow-up data to confirm these observations with respect to any study limitations.

Scoring indices for perianal fistulizing Crohn's disease: A systematic review.

In this systematic review we summarize existing scoring indices for assessing disease activity and quality of life in perianal fistulizing Crohn's disease (PFCD) and highlight gaps in the literature. MEDLINE, EMBASE, and CENTRAL were searched from 24 August 2022 to identify studies evaluating clinical, radiological, or patient-reported outcome measures (PROMS) in PFCD. The primary objective was to identify all available scoring indices and describe the operating properties of these indices. Fifty-three studies reported on the use of one clinical index (Perianal Disease Activity Index: PDAI), three PROMs and ten radiological indices. Twenty-five studies evaluated the operating properties of these indices. The PDAI demonstrated content validity, construct validity and responsiveness but criterion validity or reliability were not assessed. The Van Assche index (VAI), modified VAI and the Magnetic Resonance Index for Assessing Fistulas in Patients with CD (MAGNIFI-CD) were the most studied radiological indices. These indices demonstrated responsiveness and reliability. The VAI and MAGNIFI-CD demonstrated construct validity. Criterion and content validity and feasibility have not been assessed. Among the three PROMs, the Crohn's Anal Fistula Quality of Life index demonstrated content and construct validity, inter-observer reliability and responsiveness. Criterion validity, intra-observer reliability and feasibility have not been assessed for this index. There are no fully valid, reliable, and responsive clinical disease or radiological indices for PFCD. Although the radiological indices demonstrated responsiveness and reliability, well-defined cut-offs for response and remission are lacking. Future research should focus on establishing standardized definitions and thresholds for outcomes.

Local fistula injection of allogeneic human amnion epithelial cells is safe and well tolerated in patients with refractory complex perianal Crohn's disease: a phase I open label study with long-term follow up

Local fistula injection of mesenchymal stromal/stem cells (MSC) is effective for complex perianal Crohn's fistulas but is also expensive and requires specialised facilities for cell revival before administration. Human amnion epithelial cells (hAEC) are non-MSC cells with therapeutic properties. The primary aim of this study was safety of hAEC therapy. Secondary aims included hAEC efficacy, feasibility of the protocol and impact on quality of life. A phase I open label study of ten adults with active complex Crohn's perianal fistulas refractory to conventional treatment, including anti-tumour necrosis factor alpha therapy, was undertaken. A single dose of hAEC was injected into the fistula tract(s) after surgical closure of the internal opening(s). Study outcomes were assessed at week 24 with follow up for at least 52 weeks. Local injection of hAEC was safe, well tolerated and the injection procedure was feasible. Complete response occurred in 4 patients, and a partial response in an additional 4 patients. There was a mean reduction in the Perianal Disease Activity Index of 6.5 points (95% CI-9.0 to-4.0, p=0.0002, paired t-test), modified Van Assche MRI Index of 2.3 points (95% CI-3.9 to-0.6, p=0.012, paired t-test) and a mean improvement of 15.8 points (95% CI 4.9 to 26.8, p=0.010, paired t-test) in quality of life using the Short IBD-Questionnaire in complete responders. Local injection of hAEC therapy for refractory complex perianal fistulising Crohn's disease appears safe, well-tolerated, feasible and demonstrated improvement. Quality of life is improved in those who achieve complete fistula healing. This study was funded by competitive research grant funding from the Gastroenterological Society of Australia Seed Grant2018.

Analysis on the efficacy of dual vein induction therapy of Ustekinumab in complex perianal fistulizing Crohn's disease

Objectives: To analyze the efficacy of dual vein induction therapy of Ustekinumab (UST) in complex perianal fistulizing Crohn's disease (PFCD). Methods: Clinical data of patients diagnosed with complex PFCD in the Second Affiliated Hospital of Wenzhou Medical University from January 2022 to March 2023 were retrospectively analyzed. After sufficient single intravenous infusion of UST (6 mg/kg) at week 0 and 8, every patient received single subcutaneous injection of UST 90 mg every 8 weeks for maintenance treatment. At week 8, 16, and 22-26, clinical outcomes of anal fistula were evaluated using perianal disease activity index (PDAI), and overall activity of the patients was evaluated using Harvey Bradshaw index (HBI). At week 22-26, Van Assche Index (VAI) was used to evaluate imaging outcome of anal fistula, and simplified endoscopic score of Crohn's disease (SES-CD) was employed to assess intestinal outcome events. The above indexes were compared in the patients before and after UST treatment. PFCD patients were divided into first-line UST treatment group and non first-line UST treatment group according to whether first-line UST treatment was used, the differences in anal fistula response rate and remission rate, intestinal response rate and remission rate as well as overall activity response rate and remission rate were compared between the two groups. Results: A total of 60 PFCD patients were included, including 46 males and 14 females, aged [M (Q1, Q3)] 25.0 (20.8, 30.0) years old. The clinical response rates of anal fistula [41.7% (25/60), 55.0% (33/60) and 63.3% (38/60), respectively, P=0.056] and the clinical remission rates of anal fistula [21.7% (13/60), 31.7% (19/60) and 43.3% (26/60), respectively, P=0.002] gradually increased at week 8, 16, 22-26. The overall activity response rates [53.3% (32/60), 70.0% (42/60), 83.3% (50/60), respectively, P=0.040] and the overall activity response rates [41.7% (25/60), 61.7% (37/60), 75.0% (45/60), respectively, P=0.001] also gradually increased at week 8, 16, 22-26. At week 22-26, the partial response rate and fistula healing rate of anal fistula imaging were 45.0% (27/60) and 38.3% (23/60), respectively. The endoscopic response rate and endoscopic response rate were 73.7% (44/60) and 45.0% (27/60), respectively. The endoscopic response rate of patients receiving first-line UST treatment [23 males and 8 females, aged 22.0 (21.0, 39.0) years] was higher than that of patients receiving non first-line UST treatment[23 males and 6 females, aged 26.5 (20.0, 30.0) years,87.1% vs 58.6%, P=0.013]. Conclusion: The dual vein induction therapy of UST could effectively improve the clinical efficacy in patients with complex PFCD.

Efficacy of cx601 (darvadstrocel) for the treatment of perianal fistulizing Crohn's disease-Aprospective nationwide multicenter cohort study.

The use of mesenchymal stem cells is considered anovel and promising therapeutic option for patients with perianal fistulizing Crohn's disease; however, data on its clinical application remain scarce. This multicenter nationwide study aimed to assess the clinical efficacy of mesenchymal stem cells in closing complex anal fistulas. In this study 14 Crohn's disease patients (3males, 11females) with complex anal fistulas treated in 3 tertiary hospitals in Austria were included between October 2018 and April 2021. Injection of 120 million allogeneic expanded adipose-derived mesenchymal stem cells (Cx601-darvadstrocel) was performed in each patient. Closure of the external fistula opening without secretion by external manual compression was defined as treatment success. The median age of the patient population at the time of surgery was 32years (range 26-53years) with amedian body mass index of 21.7 kg/m2 (range 16.7-26.6 kg/m2). Of the patients 12 (86%) received monoclonal antibodies (infliximab, adalimumab, ustekinumab, vedolizumab) at the time of surgery. The median number of complex fistulas was 1.4 (range 1-2), The median operative time was 20 min (range 6-50 min) with no perioperative complications. After amedian follow-up of 92weeks, we found successful fistula closure in 57.1% (n = 8) of treated patients. The perianal disease activity index did not improve significantly from initially 7 to amedian of 6 after 52weeks (p = 0.495). Darvadstrocel is asafe, minimally invasive surgical technique without significant perioperative complications. Clinical success can be expected in about half of the treated patients.

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

Fistulizing perianal Crohn's disease (CD) is a debilitating condition associated with significant morbidity and reduction in thequality of life. Magnetic resonance imaging (MRI) of the pelvis is the preferred imaging modality for thecomprehensive assessment of the perianal fistula. There is apaucity of data from India on the MRI spectrum of complex perianal fistula in CD. 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. 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. The cumulative risk of thedevelopment 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 forthe delineation of fistula anatomy, assessment of disease extent and activity and theevaluation of concomitant perianal abscess and other complications.

Autologous Fat Grafting: an Emerging Treatment Option for Complex Anal Fistulas

BackgroundAutologous fat grafting (AFG) has shown promise in the treatment of complex wounds, with trials reporting good healing rates and safety profile. We aim to investigate the role of AFG in managing complex anorectal fistulas. MethodsThis was a retrospective review of a prospectively maintained IRB-approved database. We examined the rates of symptom improvement, clinical closure of fistula tracts, recurrence, complications, and worsening fecal incontinence. Perianal disease activity index (PDAI) was obtained for patients undergoing combination of AFG and fistula plug treatment. ResultsIn total, 52 unique patients underwent 81 procedures, of which Crohn’s was present in 34 (65.4%) patients. The majority of patients previously underwent more common treatments such as endorectal advancement flap or ligation of intersphincteric fistula tract. Fat-harvesting sites and processing technique were selected by the plastic surgeons based on availability of trunk fat deposits. When analyzing patients by their last procedure, 41 (80.4%) experienced symptom improvement, and 29 (64.4%) experienced clinical closure of all fistula tracts. Recurrence rate was 40.4%, and complication rate was 15.4% (7 postoperative abscesses requiring I&D and 1 bleeding episode ligated at bedside). The abdomen was the most common site of lipoaspirate harvest at 63%, but extremities were occasionally used. There were no statistically significant differences in outcomes when comparing single graft treatment to multiple treatments, Crohn’s and non-Crohn’s, different methods of fat preparation, and diversion. ConclusionAFG is a versatile procedure that can be done in conjunction with other therapies and does not interfere with future treatments if recurrence occurs. It is a promising and affordable method to safely address complex fistulas.

Deep remission improves the quality of life of patients with Crohn's disease and anoperineal fistula treated with darvadstrocel: results of a French pilot study.

The injection of allogeneic adipose tissue-derived mesenchymal stem cells (MSC) into anal fistulas in patients with Crohn's disease has never been evaluated in "real-life" conditions in France. We prospectively studied the first patients receiving MSC injections at our center and undergoing 12months of follow-up. The primary endpoint was the clinical and radiological response rate. The secondary endpoints were symptomatic efficacy, safety, anal continence, quality of life (Crohn's anal fistula-quality of life scale, CAF-QoL), and predictive factors of success. We included 27 consecutive patients. The complete clinical and radiological response rates at M12 were 51.9% and 50%, respectively. The combined complete clinical-radiological response (deep remission) rate was 34.6%. No major adverse effects or changes in anal continence were reported. The perianal disease activity index decreased from 6.4 to 1.6 (p < 0.001) for all patients. The CAF-QoL score also decreased from 54.0 to 25.5 (p < 0.001). At the end of the study, M12, the CAF-QoL score was significantly lower only in patients with a complete combined clinical-radiological response relative to those without a complete clinical-radiological response (15.0 versus 32.8, p = 0.01). Having a multibranching fistula and infliximab treatment were associated with a combined complete clinical-radiological response. This study confirms reported efficacy data for the injection of MSC for complex anal fistulas in Crohn's disease. It also shows a positive impact on the quality of life of patients, particularly those for whom a combined clinical-radiological response was achieved.

P615 The safety and efficacy of ustekinumab combined with sphincter-preserving surgery for perianal fistulizing Crohn’s disease:a single-center retrospective study

Abstract Background To assess the clinical efficacy and safety of ustekinumab(UST) combined with sphincter-preserving surgery in the treatment of perianal fistulizing Crohn’s disease(pfCD). Methods A single-center retrospective study. The baseline data of pfCD patients who met the inclusion and exclusion criteria and visited the Anorectal Department of the Affiliated Hospital of Nanjing University of Traditional Chinese Medicine from January 2020 to March 2022 were collected. Patients were assessed for fistula response and remission by rectal magnetic resonance image(MRI) and perianal disease activity index(PDAI). Patients' fistula response and remission were assessed by rectal MRI and PDAI. Patients were assessed for clinical response and remission by using Crohn's disease activity Index( CDAI). Patients' anal function was assessed by using the Wexner score. The differences in CDAI,PDAI and inflammatory parameters, including C-reactive protein(CRP) and erythrocyte sedimentation rate(ESR), at 0 week, 8 weeks and 16 weeks were statistically analyzed. Results A total of 64 pfCD patients were included. Fistula response was 23.4% (8 weeks), 40.6% (16 weeks), and 51.6% (follow-up endpoint); fistula remission was 21.9% (follow-up endpoint); fistula MRI remission was 9.3% (follow-up endpoint); clinical response was 68.8% (8 weeks) and 79.7% (16 weeks); and clinical remission was 46.9% (8 weeks) and 59.4% (16 weeks). CDAI, PDAI and inflammatory parameters at the 8th and 16th week of treatment were significantly lower than those before treatment (p&amp;lt;0.05). There was no significant difference in postoperative anal function (p&amp;lt;0.05). The incidence of adverse events was 1.6%. Conclusion UST combined with sphincter-preserving surgery is safe and effective in the treatment of pfCD.This therapy can effectively improve the fistula condition and systemic manifestations.

P331 Risk Factors and Prediction Model for Fecal Incontinence in Patients with Crohn’s Disease: A Multicenter Study

Abstract Background Fecal incontinence (FI) is a common complaint that seriously affects the quality of life in patients with Crohn’s disease (CD). We aimed to identify risk factors related to FI and construct a risk prediction model for FI in patients with CD. Methods Four hundred and sixty-one patients diagnosed with CD between June 2016 and April 2021 in Jiangsu Province Hospital of Chinese Medicine were retrospectively enrolled in this study and randomly divided into the development (n=368) and internal validation cohort (n=93). FI-related risk factors were selected from the development cohort using the random forest procedure and included in a logistic regression model from which the prediction model was elaborated. The discrimination, calibration and clinical benefit of the model were evaluated by examining the area under the receiver operating characteristic curves, calibration curves and decision curve analysis in internal validation and external validation (using 225 patients from four tertiary hospitals), respectively. Results Four independent variables were selected and included in the logistic regression model: body mass index, history of non-fistulizing perianal lesions surgery, the number of loose stools in the last week and perianal disease activity index. A nomogram was developed to facilitate risk score calculation. The model showed good discrimination ability with AUC was 0.798 and 0.780 in the internal and external cohorts, respectively. The calibration curves demonstrated good agreement with the model using the Hosmer-Lemeshow test in both cohorts (internal validation, P = 0.562; external validation, P = 0.383). DCA confirmed the clinical validity of the predictive model. Conclusion This study recognized four risk factors related to the prevalence of FI and developed a new model to effectively predict risk scores of FI in CD patients, helping to provide early risk stratification and timely intervention.

Short-term anti-TNF therapy with surgical closure versus anti-TNF therapy in the treatment of perianal fistulas in Crohn's disease (PISA-II): a patient preference randomised trial

Guidelines on Crohn's perianal fistulas recommend anti-tumour necrosis factor (TNF) treatment and suggest considering surgical closure for patients with surgically amenable disease. However, long-term outcomes following these two strategies have not been directly compared. The aim of this study was to assess radiological healing in patients who received short-term anti-TNF treatment and surgical closure compared with those who received anti-TNF treatment alone. The PISA-II trial was a multicentre, patient preference study done in nine hospitals in the Netherlands and one hospital in Italy. Adult patients with Crohn's disease and an active high perianal fistula with a single internal opening were eligible for inclusion. After counselling, patients with no treatment preference were randomly assigned (1:1) using random block randomisation (block sizes of six without statification), to 4-month anti-TNF therapy and surgical closure or anti-TNF therapy for 1 year, after seton insertion. Patients with a treatment preference received their preferred therapy. The primary outcome was radiological healing assessed by MRI at 18 months, defined as a complete fibrotic tract or a MAGNIFI-CD (Magnetic Resonance Index for Fistula Imaging in Crohn's Disease) score of 0, assessed according to the intention-to-treat principle. Secondary outcomes included clinical closure, number of patients undergoing surgical reintervention and number of reinterventions, recurrences, and impact on quality of life measured by the Perianal Disease Activity Index (PDAI). Analyses were performed on an intention-to-treat basis and additionally an as-treated analysis for radiological healing and clinical closure. This study was registered at the Dutch Trial Registry, NL7625, and with EudraCT, 2018-002064-15, and is closed to accrual due to completion. Between Sept 14, 2013, and Dec 7, 2019, 94 patients were enrolled onto the trial, of whom 32 (34%) were randomly assigned and 62 (66%) chose a specific treatment. 38 (40%) patients were assigned to the surgical closure group and 56 (60%) patients to the anti-TNF group. At 18 months, radiological healing was significantly more common in the surgical closure group (12 [32%] patients) than in the anti-TNF group (five [9%] patients; p=0·005). By contrast, clinical closure was not significantly different between the two treatment groups (26 [68%] patients in the surgical closure group vs 29 [52%] patients in the anti-TNF group; p=0·076). Significantly fewer patients required a reintervention in the surgical closure group than in the anti-TNF therapy group (five [13%] patients in the surgical closure group, median one reintervention [IQR one to three] vs 24 [43%] patients in the anti-TNF group, median two reinterventions [one to two]; p=0·005). Among patients who reached clinical closure during follow-up, four (14%) of 29 in the surgical closure group and five (16%) of 31 in the anti-TNF therapy group had a recurrence, which occurred only in patients without radiological healing. PDAI was significantly lower in the surgical closure group than in the anti-TNF group after 18 months (p=0·031). Adverse events and serious adverse events were similar in both treatment groups and mostly entailed reinterventions. Ten (11%) patients had side-effects associated with anti-TNF treatment. Two serious adverse events unrelated to study treatment occurred (appendicitis and myocardial infarction). One patient died from a tongue base carcinoma, unrelated to study treatment. Short-term anti-TNF treatment combined with surgical closure induces long-term MRI healing more frequently than anti-TNF therapy in patients with Crohn's perianal fistulas. These data suggest that patients with Crohn's perianal fistula amenable for surgical closure should be counselled for this therapeutic approach. Netherlands Organisation for Health Research and Development and Broad Medical Research Program.

Mesenchymal Stromal Cell Therapy Improves Refractory Perianal Fistula in Crohn's Disease: Case Series Clinical Interventional Study.

Objective Perianal fistulas in Crohn’s disease (CD) are the main challenges in inflammatory bowel diseases (IBDs). Some of the fistulas are refractory to any therapeutic strategy. The aim of this study was to evaluate the therapeutic effects of mesenchymal stromal cells (MSCs) as a novel promising modality for the treatment of fistulizing CD. Materials and Methods This case series clinical interventional study was conducted from 2014 to 2017 at Shariati Hospital, an IBD referral center in Tehran, Iran. Refractory adult patients with CD who had draining perianal fistulas were enrolled in this study. All patients were examined by a colorectal surgeon and the fistula imaging studies were performed by pelvic magnetic resonance imaging (MRI). After autologous bone marrow (BM) aspiration and MSCs isolation, the cells were cultured and passaged under current good manufacturing practice (cGMP) conditions. Four intra-fistula injections of cells, each containing 40×106 MSCs suspended in fibrin glue, were administered by an expert surgeon every 4 weeks. Procedure safety, feasibility and closure of the perianal fistulas at week 24 were assessed. Clinical examination and MRI findings were considered as the primary end points. Results In total, 5 patients (2 males and 3 females) were enrolled in this study. No adverse events were observed during the six-month follow-up in these patients. Both the Crohn’s Disease Activity Index (CDAI) and Perianal Disease Activity Index (PDAI) scores decreased in all patients after cell injections and one patient achieved complete remission with closure of fistulas, discontinuation of fistula discharge, and closure of the external opening. ConclusionLocal injection of MSCs combined with fibrin glue is potentially a safe and effective therapeutic approach for complex perianal fistulas in patients with CD.