Perianal Crohn's disease (pCD) is a complex manifestation of Crohn's disease. Classifying this patient cohort for both clinical purposes and for inclusion into research trials is challenging but crucial in order to improve outcomes. This review provides an overview of historical classifications of both fistulising and non-fistulising pCD, including the Park's, Cardiff-Hughes and American Gastroenterological Association (AGA) classifications, as well as recent advances including the Treatment Optimisation and CLASSification of perianal Crohn's disease (TOpClass) classification of fistulising pCD. Secondly, this article provides a scoping review of recent trials in pCD and describes how the cohorts in these trials relate to the TOpClass classification. Of the 19 studies relating to pCD that were identified, four could be confidently classified as class 2a. Seven could be classified as class 2a or 2b, but it was not possible to subdivide further, and seven to class 2a, 2b or 2c, but it was not possible to subdivide further. One study population was classified as class 2a or 2c. In eight studies, it was not specified whether patients with a defunctioning stoma were included or excluded. This review demonstrates the heterogeneous nature of some patient cohorts in previous clinical trials, and how the TOpClass classification may be used to group patients more accurately for clinical use and inclusion in research trials.

A case-based survey was conducted to identify practice patterns and knowledge gaps in the management of Crohn's perianal fistulas (CPF) and to further understand approaches to CPF management within the USA by healthcare professionals (HCPs) from different specialties.

The web-based survey, comprising two hypothetical patient case vignettes (case 1: initial CPF presentation and progression to partial response; case 2: recurrent CPF), was distributed September-October 2020 to US gastroenterologists (GEs) and colorectal surgeons (CRSs), and nurse practitioners (NPs) and physician assistants (PAs) from these specialties, who managed ≥1 patient with CPF/month. The survey included questions on clinician evaluation and treatment approach.

Across surveyed HCPs (127 GEs, 63 GE NP/PAs, 78 CRSs and 14 CRS NP/PAs), 39% stated that they did not use any standard system for classifying/scoring CPF. On initial CPF presentation, ≥98% of HCPs reported a requirement for additional diagnostic/imaging evaluation before proceeding with medical management; GEs preferred pelvic MRI (70%) and CRSs preferred examination under anaesthesia (62%). Preferred management after partial response to initial treatment varied by HCP type (23% GEs vs 71% CRSs preferred continuation of current medical therapy; 60% vs 38% preferred seton continuation; 24% vs 41% preferred seton removal, respectively). For recurrent CPF, most HCPs chose to switch from infliximab to another antitumour necrosis factor agent, while most GEs opted to switch to a different monoclonal antibody. In contrast, 44% of GEs and 27% of CRSs opted to proceed with surgery.

Lack of consensus in CPF management requires improved coordination in treatment approaches among specialists.

Surgical treatment for perianal fistulas requires balancing fistula closure with the risk of complications such as incontinence. The advancement flap (AF) is a widely used sphincter-sparing technique, yet it appears to offer only marginally better outcomes compared to alternative techniques, with a notable incontinence rate. This study aimed to evaluate the success rate and long-term functional outcomes of AF at our tertiary referral center.

This retrospective cohort study analyzed prospectively collected data from electronic medical records and questionnaires distributed in December 2023. Patients aged 18 or older with primary or recurrent perianal fistulas treated with AF between 2013 and 2023 were included. Fistulas of non-cryptoglandular origin and rectovaginal fistulas were excluded. The primary outcome was fecal incontinence. Secondary outcomes included disease burden, fistula closure, and risk factors for recurrence.

Eighty-one patients were included; 37 (46%) were women, mean age was 45 years, and 93% had a complex fistula. The median follow-up was 27 months (IQR 15.5-64). Before AF, 36% reported some degree of incontinence, increasing to 80% at long-term follow-up after AF. Specifically, 20 out of 26 (77%) preoperative fully continent patients reported incontinence issues at long-term follow-up. Fistula disease impact on daily life was higher for those who failed AF repair. Primary fistula closure was achieved in 35 patients (43%). No risk factors for AF failure could be identified.

Advancement flap repair of perianal fistulas is challenging and can lead to fecal incontinence, so thorough preoperative counseling, consistent long-term follow-up, and further research comparing alternative sphincter-sparing techniques are warranted.

Anal fistula treatment remains a surgical challenge. This study focuses on the efficiency and safety of the Ligation of Intersphincteric Fistula Tract (LIFT) procedure for high intersphincteric anorectal fistulas, aiming to identify prognostic factors for success and complications. A retrospective chart review was conducted on all patients who underwent LIFT procedure at a tertiary referral hospital between January 2013 and January 2021. The primary endpoint was the success rate of fistula closure, confirmed with clinical investigation. Secondary endpoints included postoperative complications, reintervention and self-reported incontinence. Logistic regression analyses were performed for assessing prognostic factors for fistula closure and postoperative complications. Ninety-two patients were included in the study; after a median follow-up of 19.3 months, fistula closure was achieved in 71% (n = 65) and in 89% (n = 82) after reinterventions. 46% (n = 42) reported persistent symptoms, although 83% of which (n = 32/42) had succesful fistula tract closure by clinical evaluation. One patient developed incontinency for gas. Smoking emerged as a significant risk factor for fistula closure failure, OR = 6.75, 95% CI = [1.65, 27.69], p = 0.030. Wound dehiscence was the most common complication, occuring in 25% (n = 23). Prolonged oral antibiotics demonstrated a significant protective effect against wound dehiscence, OR = 0.31, 95% CI = [0.10, 0.96], p = 0.036. The LIFT procedure is an efficient and safe treatment for complex perianal fistula. Patient satisfaction emerged as a crucial treatment goal, as patients can remain symptomatic after fistula closure. Emphasizing smoking cessation is integral to the treatment approach. The findings suggest prolonged antibiotic treatment as a potential preventive measure for wound dehiscence.

MR imaging is the gold standard for diagnosis, providing detailed evaluation of perianal fistulas. MR imaging aids in detecting, classifying, and monitoring fistulas and guiding treatment. Detailed radiology reports, incorporating patient history and disease-specific considerations, are essential for effective management and improved clinical outcomes. This review overviews fundamental high-yield concepts to aid radiologists in interpreting MR imaging for perianal fistulas with multiple case examples.

The Sumikoshi classification for anal fistulas is widely used in Japan; however, it does not include a category for transsphincteric fistulas. Therefore, low transsphincteric fistulas were included in type IIL (low intersphincteric) for convenience; however, high transsphincteric fistulas have not been properly classified. We defined high transsphincteric fistulas as type IIT and investigated their prevalence and clinical characteristics.

Consecutive patients who underwent fistula surgery at our hospital were included. The operative and endoanal ultrasonography records were retrospectively reviewed, and the following cases were reclassified as type IIT: cases documented as transsphincteric fistulas or cases with written records and/or illustrations indicating that the fistula tract penetrated the upper two-thirds of the external anal sphincter.

Of the 1,069 eligible patients, 895 (83.7%) had type II (intersphincteric) fistulas. Among the type II subtypes, type IIL was the most common with 771 (86.1%) patients, whereas type IIT accounted for 54 (6.0%) patients. The direction of the primary opening was more posterior (62.2%) in patients with type II fistulas other than type IIT, but it was more anterolateral (55.6%) in patients with type IIT fistulas. Patients with type IIT fistulas were more likely to undergo sphincter-sparing surgery than patients with other type II fistulas (37.0 vs. 3.7%, p<0.001).

Type IIT is not rare (6.0%) and should be treated as a complex fistula because of the greater involvement of the external anal sphincter. Surgeons may benefit by including type IIT as a new type II subclass in the Sumikoshi classification system.

Perianal fistulising Crohn's disease (PFCD) is a debilitating phenotype of Crohn's disease, with a lifetime incidence of 20-30% in people living with the dieases. Symptoms include perianal pain, perianal discharge and faecal incontinence, with repercussions for a patient's physical and mental health, psychosocial wellbeing and productivity. PFCD is challenging to treat, with existing therapeutic options achieving modest fistula remission rates only. While research initiatives are under way to characterise PFCD pathogenesis and optimal treatment approaches, the focus should be on early diagnosis and prompt management. This can be achieved with patient education, effective co-ordination of care within the multidisciplinary team and an accessible inflammatory bowel disease (IBD) service. IBD specialist nurses may be the first health professionals to encounter a patient with a new diagnosis of PFCD or its complications. This review article summarises the existing evidence relating to clinical aspects of PFCD from a multiprofessional perspective and discusses the role of a dedicated IBD surgical link nurse in PFCD management in a tertiary centre setting.

The ligation of the intersphincteric fistula tract (LIFT) procedure has garnered popularity with its success rates and purported sphincter-continence preservation. However, there remains a paucity in the literature on the objective evaluation of sphincter integrity and fecal continence after the LIFT procedure.

The present study undertakes a scoping review to systematically explore and map the published literature, to evaluate the sufficiency of data on the impact on continence in patients after the LIFT procedure.

A systematic search of MEDLINE, PubMed, EMBASe, CINAHL was performed from January 2007 to April 2020 and 597 publications were identified. Forty-two satisfied the inclusion and exclusion criteria. We performed a scoping review in accordance to the PRISMA-ScR guidelines.

Only 3 (7.1%) of publications were randomized controlled trials, of which just 1 (2.4%) measured incontinence as a primary outcome. Continence was measured both pre- and post-LIFT in 30 (71.4%), of which 19 (45.2%) had a fixed protocol for continence assessment, which was heterogeneous between the studies. Continence was assessed using subjective scoring systems in 27 (64.3%) and objective measurement was performed in just 6 (14.3%). No studies performed post-operative anatomical assessment of the anal sphincter complex.

Long-term continence in post-LIFT patients is not supported with adequately powered prospective longitudinal trials using rigorously protocoled pre- and post-operative assessment of continence. Future research that focuses on a combination of objective assessment using anal manometry as well as anatomical assessment of the sphincter complex on top of subjective evaluation is needed before we can be certain if LIFT is indeed a sphincter and continence preserving technique.

Background: Managing perianal fistulae involves balancing the risks of incontinence and recurrence, with existing classification systems offering limited guidance for surgical decision-making. Garg's classification provides a detailed assessment of fistula anatomy, aiding the choice between fistulotomy and sphincter-sparing procedures. This study evaluates its predictive accuracy.

The management of perianal Crohn's disease is challenging and complex and requires a multidisciplinary approach as a favorable working relationship between gastroenterologists and colorectal surgeons is necessary to provide excellent care for this patient population. The use of biologic therapy has impacted the treatment of this disease process, but surgical options have failed to reach the success rates seen in cryptoglandular and traumatic pathologies of the anus. The general management of perianal disease involves control of sepsis, control of anorectal symptoms, minimizing resultant complications and avoidance of proctectomy when possible.

We aimed to assess inter-radiologist agreement when interpreting pelvic MRI in children with newly diagnosed perianal Crohn's disease (CD).

In this retrospective multi-reader study, we identified pediatric patients (< 18 years of age) who underwent a pelvic MRI examination for newly diagnosed perianal CD. Images were de-identified and uploaded to a cloud-based image platform for review by 13 fellowship-trained pediatric radiologists The reviewers assessed for the presence of a fistula and abscess, categorization of different imaging findings, and classification using the Parks and St James' University Hospital systems. Fleiss' kappa (κ) statistics and intra-class correlation coefficients (ICC) were used to measure inter-reader agreement, along with 95% confidence intervals (CI).

Forty-six patients were included in our study (median age = 13.0 years [IQR: 10.5 to 16.0 years]); thirty-five (76.1%) were boys. Most imaging features showed fair agreement (κ = 0.21 to 0.35). There was moderate agreement for categorical fistula length (κ = 0.42 [95% CI: 0.32 to 0.53]), involvement of the genitalia (κ = 0.45 [95% CI: 0.26 to 0.63]), and presence of an abscess/collection (κ = 0.52 [95% CI: 0.31 to 0.73]). Maximum abscess/collection length had good agreement (ICC = 0.81 [95% CI: 0.41, 1.00]). There was an almost equal split (yes vs. no: 50.7% vs. 49.3%) regarding whether postcontrast T1-weighted images added value compared to T2-weighted images alone across all radiologists and examinations.

Inter-radiologist agreement when interpreting pelvic MRI for perianal CD in children is fair for most imaging features, with fewer features demonstrating moderate or good agreement.

Question Pelvic magnetic resonance imaging (MRI) is used for diagnosing and monitoring children with perianal Crohn's disease (CD). Limited information is known about inter-radiologist agreement. Findings Agreement between pediatric radiologists when interpreting MRI for perianal CD in children is only fair for most imaging features (κ = 0.21 to 0.35). Clinical relevance Understanding MRI inter-radiologist agreement is crucial to improve the reliability of pelvic MRI in children with perianal Crohn's disease since it may affect patient management (e.g., surgery); further radiologist education and improved imaging feature definitions may help improve inter-radiologist agreement.

Deep postanal abscesses (DPAs) are uncommon but clinically significant conditions that, if left untreated, can result in severe septic complications. This case report presents a rare instance of sacrococcygeal osteomyelitis as a complication of a long-standing DPA. The patient underwent surgical drainage and seton placement, leading to complete resolution of both the abscess and the osteomyelitis. This case underscores the importance of prompt surgical intervention in the management of DPAs and highlights the potential for rare but serious complications such as osteomyelitis.

It is a priority to find surgical techniques that guarantee acceptable healing rates without sequelae in the treatment of complex anal fistula. The concept of the deep intersphincteric space as the origin of perianal sepsis has provided a new perspective, allowing the emergence of techniques such as TROPIS (Transanal Opening of Intersphincteric Space), with few published series to date. The aim of this study is to evaluate the healing rate and complications one year after the TROPIS technique as a treatment for complex anal fistula without hospitalization.

Prospective, observational study from January 2021 to January 2023. Patients with complex anal fistulas who met the inclusion criteria were treated using the TROPIS technique. A one-year follow up review was conducted, assessing healing rates, recurrence, continence, and complications.

A total of 23 patients with cryptoglandular complex perianal fistula were included (87% male, mean age 54.7 ± 9.6 years). 78.3% were treated for recurrent fistulas with an average of 3.3 ± 3.2 previous interventions. At one month, 82.6% of the patients had complete healing. At three, six, and twelve months, complete healing occurred in 63.6%, 61.9%, and 55.6%, respectively. One patient developed an abscess at one month. Continence was altered in 8.7%.

The treatment of cryptoglandular complex anal fistula with this procedure was safe and showed acceptable healing rates.

Surgical repair for high anal fistulas is challenging and can be associated with impaired functional outcomes. This study evaluated the long-term results of transsphincteric fistulectomy with primary sphincter repair for high anal fistulas in terms of recurrence, wound healing, fecal incontinence, and quality of life.

This retrospective cohort study included patients who underwent surgical repair for high anal fistulas between 2006 and 2015. Data were collected by reviewing patients' electronic hospital records, including demographic characteristics, medical conditions, surgical findings, performed procedures, and follow-up data until the last recorded visit. Functional outcomes were assessed using self-reported online questionnaires for quality of life (RAND SF-36) and fecal incontinence (Wexner score).

Fifty-five patients were included. Primary healing was achieved in 42 (76%) patients, while 13 (24%) experienced recurrence. Following reoperations for recurrence, an additional 12 patients achieved healing, resulting in an overall healing rate of 98%. The median Wexner score was significantly higher in reoperated patients, and the median scores across all eight parameters of the RAND SF-36 were lower. None of the patients required proctectomy, and two ended with permanent stomas.

Surgery for high anal fistulas is associated with a high success rate, but reoperations for recurrence are linked to considerable impairment in functional outcomes.

Perianal fistulizing disease, commonly associated with Crohn's disease, poses significant diagnostic and therapeutic challenges due to its complex anatomy and high recurrence rates. Radiological imaging plays a pivotal role in the accurate diagnosis, classification, and management of this condition. This article reviews the current radiological modalities employed in the evaluation of perianal fistulizing disease, including magnetic resonance imaging (MRI), endoanal ultrasound, and computed tomography (CT). MRI, recognized as the gold standard, offers superior soft tissue contrast and multiplanar capabilities, facilitating detailed assessment of fistula tracts and associated abscesses. CT, although less detailed than MRI, remains valuable in acute settings for detecting abscesses and guiding drainage procedures. This article discusses the advantages and limitations of each modality, highlights the importance of standardized imaging protocols, and underscores the need for interdisciplinary collaboration in the management of perianal fistulizing disease. Future directions include advancements in imaging techniques and the integration of artificial intelligence to enhance diagnostic accuracy and treatment outcomes.

Faecal calprotectin (FC) is a noninvasive marker that reflects intestinal inflammation with good sensitivity. A prior study indicated that FC values above 150 μg/g could distinguish between anal fistulas (AF) of cryptoglandular or Crohn's disease (CD) origin. It is hypothesized as a useful triage test to rule out CD in newly referred AF patients, thus reducing the number of ileocolonoscopies performed and optimizing treatment regimens in AF while minimizing patient discomfort as well as healthcare costs. The aim of the study was to determine the accuracy of FC in distinguishing between anal fistulas of cryptoglandular and CD origin, as well as compare characteristics in fistulas.

Patients referred with anal fistula who had an FC measurement and either ileocolonoscopy or colonoscopy within 12 weeks were included. Demographic and clinical characteristics were registered. Area under the curve (AUC) was calculated as well as sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy.

A total of 63 patients were included (CD n = 31, 49%). FC was significantly higher in CD compared to cryptoglandular fistulas, even when CD was medically treated or had no luminal activity on endoscopy. FC ≥110 μg/g was significantly associated with CD (OR 12.5; 95% CI: 3.77-41.4) p < 0.0001. This was found by plotting a receiver operating characteristic (ROC) curve, with AUC 80.8 (95% CI: 0.6952-0.9217). Sensitivity and specificity were 0.76 and 0.80, respectively (PPV 76%, NPV 80% and accuracy 78%).

FC discriminates CD from cryptoglandular fistulas, even in medically treated CD with normal endoscopic findings.

Fistula-in-ano is an abnormal tunnel formation linking the anal canal with the perineum and perianal skin. Multiple imagining methods are available to evaluate it, among which magnetic resonance imaging (MRI) is the most advanced noninvasive preoperative method. However, it is limited in its visualization function.

To investigate the use of intraluminal MRI for perianal fistulas via a novel direct MRI fistulography method.

We mixed 3% hydrogen peroxide (HP) with gadolinium for HPMRI fistulography, retrospectively analyzing 60 cases of complex/recurrent fistula-in-ano using physical examination, trans-perineal ultrasonography (TPUS), low-spatial-resolution MRI, and high-resolution direct HPMRI fistulography. We assessed detection rates of fistula tracks, internal openings, their relationship with anal sphincters, and perianal abscesses using statistical analyses, including interobserver agreement (Kappa statistic), and compared results with intraoperative findings.

Surgical confirmation in 60 cases showed that high-resolution direct HPMRI fistulography provided superior detection rates for internal openings (153) and fistula tracks (162) compared to physical exams, TPUS, and low-spatial-resolution MRI (Z > 5.7, P < 0.05). The effectiveness of physical examination and TPUS was also inferior to that of our method for detecting perianal abscesses (54) (Z = 6.773, 3.694, P < 0.05), whereas that of low-spatial-resolution MRI was not significantly different (Z = 1.851, P = 0.06). High-resolution direct HPMRI fistulography also achieved the highest interobserver agreement (Kappa: 0.89, 0.85, and 0.80), while low-spatial-resolution MRI showed moderate agreement (Kappa: 0.78, 0.74, and 0.69). TPUS and physical examination had lower agreement (Kappa range: 0.33-0.63).

High-resolution direct HPMRI fistulography enhances the visualization of recurrent and complex fistula-in-ano, including branched fistulas, allowing for precise planning and improved surgical outcomes.

High complex anal fistula is a clinical challenge for proctologists and a nightmare for patients. Although the sphincter-sparing approach seems an ideal surgical intervention, there remains room for improvement in treatment efficacy. Herein, we introduce an enhanced sphincter-sparing approach, namely the fistula occlusion with the internal sphincter flap (FOISF), for treating high complex anal fistulas.

This study evaluated 15 patients with high complex anal fistulas who underwent FOISF between October 2021 and December 2022 in the Sixth Affiliated Hospital, Sun Yat-sen University (Guangzhou, P. R. China). Data on success rates, anal function, and various surgical characteristics were subjected to rigorous analysis.

All patients underwent the FOISF procedure, with a median operation time of 53 min. Fourteen patients achieved primary intention healing, while one patient healed by second intention. No recurrence was observed over a follow-up period of 14-30 months. All patients exhibited satisfactory anal continence, with no statistically significant difference observed between preoperative and postoperative Wexner scores (P = 0.331). A significant improvement in the quality of life was observed when compared with the preoperative assessment (P < 0.001).

The preliminary results of the FOISF procedure present an effective approach to treat high complex anal fistula.

Perianal fistulas of Crohn's disease (CD) create a significant burden on patients' lives. However, the efficacy and safety of adipose-derived mesenchymal stem cell treatment are contradicting, and real-world evidence is lacking.

To examine the usability of darvadstrocel therapy in managing perianal CD.

We enrolled patients with CD and perianal fistulas in this retrospective multicenter study. The primary outcome was perianal clinical remission (defined as all treated fistulas closed) at weeks 26 and 52. Secondary outcomes were clinical response rates (≥ 1 fistulas closed), perianal activity (PDAI), patient satisfaction, and adverse events. Data were recorded at baseline and weeks 12, 26 and 52. Prediction of primary outcomes was performed by logistic regression.

Overall, among 223 patients (male/female ratio: 0.48), perianal clinical remission was achieved in 78.2% and 62.3% until weeks 26 and 52. Baseline PDAI score (OR 0.75), number of fistulas (OR 0.28) and the number of weeks after preparation for surgery (OR 0.98) were associated with treatment failure. The clinical response rates were 84.8% and 79.8% at weeks 26 and 52. Improvement of subjective perianal symptoms was achieved in 77.8% and 78.4% of patients, respectively. Adverse events occurred in 13.5% of patients; perianal abscesses and proctalgia were the most frequently reported.

Effectiveness data were higher than in clinical trials. The safety profile was reassuring, and patients' satisfaction was high. Appropriate patient selection, fistula preparation and expertise may help to achieve treatment success.

Perianal fistulas have posed a medical and surgical problem since ancient times. The plethora of surgical operations described nowadays for anal fistula treatment is real proof that there is no ideal therapeutic procedure. The cornerstone of all approaches is the equilibrium between the definitive treatment of the fistula with the maintenance of the anal continence mechanism, i.e., anal sphincters. Especially complex anal fistulas (multiple tracts, high transphincteric fistulas, rectovaginal and Crohn disease-associated anal fistulas) are difficult to deal with to preserve this therapeutic balance. Contemporary experimental procedures include the use of autologous biological products such as platelet-rich plasma (PRP) and mesenchymal stem cells (MSCs), either in their "raw" matrix (stromal vascular fraction, SVF) or after isolation and cultivation before delivered to the patient. Herein, we present a new experimental procedure that we implemented for four patients with perianal fistulas, which is safe and effective, easily reproduced, and cheap. It is a one-stage procedure that requires only simple means and could serve as a first-line approach in complex anal fistulas. In this article, we will present four indicative cases treated with this method, using different syringes for various patient conditions, while analyzing the corresponding clinical and imaging results.

Perianal abscesses are common presentations and reasons for emergency general surgery admissions. Management involves incision and drainage of the abscess and packing the cavity with internal wound dressings. This meta-analysis aimed to assess in adults if packing an abscess or leaving it unpacked leads to a significant difference in the outcomes of pain on wound dressing, time to healing, rate of fistulation and abscess recurrence.

Randomised controlled trials (RCTs) with participants aged 18 years or older that compared packing of perianal abscess cavities with no packing between 2002 and 2022 were searched for in December 2022 on OVID Medline and Embase, the CENTRAL register of trials, PubMed and Google Scholar. Risk of bias was assessed using the Cochrane Risk of Bias tool. Random effects meta-analysis was conducted on the data extracted.

Three RCTs involving 490 patients were analysed for the outcomes of abscess recurrence and postoperative fistula formation; the data were not adequate to assess pain on dressing and time to healing. For unpacked versus packed, the pooled relative risk of abscess recurrence was 1.57 (95% confidence interval (CI) 0.764, 3.29, p=0.219) and for fistula formation 0.686 (95% CI 0.430, 1.09, p=0.114). These results suggest there is no significant benefit to packing abscess cavities.

Analysis of the outcomes suggests there is no significant difference with regards to rates of abscess recurrence or fistula formation between the packed and unpacked groups; however, appropriately powered RCTs are required in this area to provide more primary evidence to inform best practice and clinical management.

Complex perianal fistulas, challenging to treat and prone to recurrence, often require surgical intervention that may cause fecal incontinence and lower quality of life due to large surgical wounds and potential sphincter damage. Human umbilical cord-derived MSCs (hUC-MSCs) and their exosomes (hUCMSCs-Exo) may promote wound healing.

This study assessed the efficacy, mechanisms, and safety of these exosomes in treating complex perianal fistulas in SD rats. We established a rat model, divided rats with fistulas into the control and the exosome groups. We assessed treatment efficacy through ultrasound, clinical observations, and histopathological analysis. We also evaluated the activation of the HIF-1α/TGF-β/Smad signaling pathway via PCR and Western blot and assessed serological markers for HIF-1α and inflammatory indices through ELISA. We analyzed gut microbiota and the systemic metabolic environment via untargeted metabolomics.

The hUCMSCs-Exo effectively promoted healing of wound, regulated the immune balance enhanced collagen synthesis and angiogenesis in the perianal fistulas model of rats, and regulated the gut microbiota and metabolomic profiles. Results of PCR and Western blot analyses indicated that the exosomes activated HIF-1α/TGF-β/Smad signaling pathways. To the dosages tested, the 10ug/100ul concentration (medium dose) was found to be the most effective to the treatment of complex perianal fistulas.

The hUCMSCs-Exo significantly promoted the healing of wound in perianal fistulas of rats and demonstrated higher safety. The underlying mechanism facilitating the healing process was likely associated with the activation of the HIF-1α/TGF-β/Smad signaling pathway.

The main goals of surgery for fistula-in-ano are to completely resolve the condition and maintain optimal anal function. Effective management of the internal opening during and proper postoperative drainage of the intersphincter plane are crucial for achieving successful outcomes. This study evaluated the clinical efficacy of a novel sphincter-sparing technique for treating high transsphincteric anal fistula (HTAF).

This prospective study included 55 patients with HTAF who underwent closed trans-intersphincteric fistulotomy (CTiF) between July 2021 and April 2022 at our institution. Preoperative anorectal magnetic resonance imaging was performed for all patients. The primary outcome measures assessed the rate of fistula healing while the secondary outcome measures evaluated healing time, Cleveland Clinic Florida fecal incontinence score (CCF-FIS), 11-point visual analog scale (VAS) pain score and postoperative complications.

We included 55 patients with HTAF in this study. During a mean follow-up period of 9.3 months, CTiF achieved a healing rate of 90.91% (50/55). The mean time to recovery was 7.09 ± 1.94 weeks. Four (7.27%) patients developed postoperative urinary retention. At the 6-month follow-up, the CCF-FIS and VAS score were 0 [(0,0) range, 0-3] and 0 [(0,1); range, 0-4], respectively. Two patients with recurrent HTAF recovered after treatment with a transanal opening of intersphincteric space procedure, and three recovered after seton placement.

CTiF is a promising and effective sphincter-sparing technique for treating HTAF. To confirm long-term outcomes, larger sample size prospective randomized controlled trials are required.

Although various sphincter-preserving techniques exist for treating anal fistulas, none have demonstrated clear superiority. Therefore, the aim of this study was to introduce a novel sphincter-preserving technique for anal duct ligation and muscle closure (ALMC) and analyse its perioperative outcomes.

The data for patients who underwent ALMC for fistula-in-ano at Seoul Song Do Hospital between 2009 and 2023 were retrospectively reviewed. Patient demographics, intraoperative information and postoperative outcomes were assessed. The main outcomes were recurrence and wound healing. Recurrence was defined as the presence of a fistula tract or discharge more than 12 weeks after the primary surgery after achieving complete healing. Faecal incontinence was also investigated clinically.

Overall, 556 patients (84.0% male; mean age 41.7 ± 12.3 years) underwent ALMC. Among these, 152 (27.3%) had a history of fistula surgery and 261 (46.9%) had suprasphincteric fistulas. Fistula-in-ano recurred in 33 patients (5.9%), wound healing was delayed in 97 (17.4%) and faecal incontinence was observed in 12 (2.2%). The mean follow-up duration was 10.0 ± 16.0 months, and the average duration until recurrence was 13.8 ± 10.7 months. The proportion of suprasphincteric fistulas was similar in those who experienced recurrence and those who did not (57.6% vs. 46.3%, respectively; p = 0.239). The proportion of suprasphincteric fistulas in the delayed wound healing group was slightly higher, although the differences were not statistically significant (56.7% vs. 44.9%, respectively; p = 0.054).

ALMC appeared to be a safe and feasible option for treating anal fistulas, providing good perioperative outcomes, particularly when sphincter preservation was crucial.

This study aimed to assess the correlation between preoperative magnetic resonance imaging (MRI) findings and intraoperative observations in patients diagnosed with anorectal fistulas and evaluate the diagnostic accuracy of MRI in identifying fistulous tracts, internal openings, and associated complications.

A prospective study was conducted at Pt. JNM Medical College, Raipur, from April 2018 to September 2019, involving 30 patients diagnosed with anorectal fistulas. Preoperative MRI scans were performed for all patients, and findings were compared with intraoperative observations. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MRI in detecting internal openings, fistulous tracts, and abscesses were calculated.

Among the 30 patients, 26 were male (86.66%) and 4 were female (13.33%), with a mean age of 35.6 years. MRI identified 63.33% of cases as simple fistulas and 36.66% as complex fistulas. The internal opening was most commonly located at the 6 o'clock position (26.66%). MRI findings correlated with intraoperative findings in 86.66% of cases. The sensitivity of MRI was 100% for detecting simple tracts and 80% for detecting abscesses, with discrepancies observed in 13.33% of cases.

MRI proved to be a valuable tool in the preoperative evaluation of anorectal fistulas, demonstrating high accuracy in identifying fistulous tracts and associated complications. However, in some cases, intraoperative findings differed from MRI, emphasizing the need for thorough surgical exploration.

This article discusses the literature review article by Pacheco et al published in July 2024; the authors provided good reviews of perianal Crohn's disease (CD), and challenges faced by clinicians in the management. CD, characterized by its chronic and relapsing nature, is an idiopathic condition that can involve any segment of the gastrointestinal tract. Perianal disease impacts up to 40% of patients with CD, with perianal fistulas constituting up to 80% of perianal lesions. Perianal CD can be highly incapacitating and profoundly diminish the overall well-being of patients. The management focuses on controlling the perianal sepsis and treating luminal CD. Biologics are crucial to the treatment approach, and results have been encouraging. The surgery focuses on controlling the sepsis, with more definitive treatments being fistula surgery, fecal diversion, and proctectomy as the last resort. This manuscript briefly describes the burden of CD, the challenges posed by perianal CD, and the role of different treatment modalities from colorectal surgeon's perspective.

Diagnosis of perianal fistula represents a challenge for surgeons. It is well known that magnetic resonance imaging (MRI) plays an important role in that. The new 3D MRI sequence VISTA (Volume ISotopic Turbo spin echo Acquisition) can improve detection and characterization of perianal fistula compared with two-dimensional (2D) sequences. The aim of the study was to compare the diagnostic performance of the new 3D MRI sequence VISTA with the widely routinely used T2 FSE pulse sequence in depiction and characterization of perianal fistula by using the contrast-enhanced (CE) 3D T1 sequence THRIVE (T1-weighted high-resolution isotropic volume examination) as a reference standard.

Forty adult patients were enrolled in this prospective study. They underwent MRI perianal region examination using routine T2 TSE and CE 3D T1 sequence THRIVE with addition of the new 3D MRI sequence VISTA. T2, 3D VISTA and (CE) 3D T1 sequence THRIVE images were evaluated by two radiologists separately for detection and characterization of perianal fistula, then comparison between of T2 and 3D VISTA sequences was done using (CE) 3D T1 sequence THRIVE as a reference. Each sequence sensitivity, specificity and accuracy were calculated by both readers.

For reader 1, the sensitivity, specificity and accuracy were 92.5%, 90.5% and 93.6% for 3D VISTA and 84.1%, 83.7% and 87.3% for T2 FSE. For reader 2, the sensitivity, specificity and accuracy were 91.5%, 92.8% and 94.8% for 3D VISTA and 82.9%, 84.5% and 86.7% for T2 FSE.

Using CE 3D T1 sequence THRIVE as the reference standard, 3D VISTA pulse sequence on the perianal region has better diagnostic performance in the detection and characterization of perianal fistula as compared to the routinely used T2 FSE sequence.

Perianal fistulas are a debilitating complication of Crohn's disease (CD). Due to unknown reasons, CD-associated fistulas are in general more difficult to treat than cryptoglandular fistulas (non-CD-associated). Understanding the immune cell landscape is a first step towards the development of more effective therapies for CD-associated fistulas. In this work, we characterized the composition and spatial localization of disease-associated immune cells in both types of perianal fistulas by high-dimensional analyses.

We applied single-cell mass cytometry (scMC), spectral flow cytometry (SFC), and imaging mass cytometry (IMC) to profile the immune compartment in CD-associated perianal fistulas and cryptoglandular fistulas. An exploratory cohort (CD fistula, n = 10; non-CD fistula, n = 5) was analyzed by scMC to unravel disease-associated immune cell types. SFC was performed on a second fistula cohort (CD, n = 10; non-CD, n = 11) to comprehensively phenotype disease-associated T helper (Th) cells. IMC was used on a third cohort (CD, n = 5) to investigate the spatial distribution/interaction of relevant immune cell subsets.

Our analyses revealed that activated HLA-DR+CD38+ effector CD4+ T cells with a Th1/17 phenotype were significantly enriched in CD-associated compared with cryptoglandular fistulas. These cells, displaying features of proliferation, regulation, and differentiation, were also present in blood, and colocalized with other CD4+ T cells, CCR6+ B cells, and macrophages in the fistula tracts.

Overall, proliferating activated HLA-DR+CD38+ effector Th1/17 cells distinguish CD-associated from cryptoglandular perianal fistulas and are a promising biomarker in blood to discriminate between these 2 fistula types. Targeting HLA-DR and CD38-expressing CD4+ T cells may offer a potential new therapeutic strategy for CD-related fistulas.

Endoanal ultrasound for the diagnosis of anal fistulas requires the injection of hydrogen peroxide, but it is often uncomfortable for the patient and has the potential to cause complications. Novel ultrasound contrast is currently available.

To assess the efficacy and safety of sulfur hexafluoride as an ultrasound contrast agent for the diagnosis of a perianal fistula by comparing it with those of 50% diluted hydrogen peroxide.

Double-blinded superiority study with 4 consecutive visits to perform an ultrasound without contrast, a hydrogen peroxide-enhanced ultrasound, a sulfur hexafluoride-enhanced ultrasound, and a rectal exploration in the operating room (the criterion standard). The 3 expert surgeon sonographers independently reviewed the ultrasound images.

This study was conducted at a single university hospital.

Data from 176 patients were evaluated.

Demographic and exploratory data and the ultrasound findings related to the location of the internal fistula orifice, description of the primary and secondary tracts, and presence of cavities and sphincter defects were analyzed. Complications occurring before and after the contrast agent administration and pain score measured using a visual analog scale were considered.

Eighty-eight patients were included (men: 71.5%; mean age: 48.3 years), with 62.5% having a complex type fistula and 83.7% having a transsphincteric type fistula. Sulfur hexafluoride-enhanced ultrasounds demonstrated a higher interobserver agreement in determining the secondary tracts (κ = 0.604) and anal fistula height (κ = 0.604) compared with other methods. Both hydrogen peroxide-enhanced ultrasound (90.91%) and sulfur hexafluoride-enhanced ultrasound (89.77%) detected the internal orifice more frequently than ultrasounds without contrast (62.5%; p < 0.001), with no differences between contrast agents ( p = 0.810). Sulfur hexafluoride-enhanced ultrasound was less painful than peroxide-enhanced ultrasound ( p < 0.001).

Most of the patients had transsphincteric anal fistulas.

Sulfur hexafluoride proved comparable to hydrogen peroxide in evaluating fistulous tracts and identifying the internal orifice, and it significantly reduced pain and discomfort. Furthermore, it demonstrated a higher interobserver agreement in determining the secondary tracts and anal fistula height compared with other methods. See Video Abstract .

ANTECEDENTES:La ecografía endoanal para el diagnóstico de fístulas anales requiere la inyección de peróxido de hidrógeno, pero generalmente resulta incómoda para el paciente y presenta potenciales complicaciones. Actualmente se encuentran disponibles nuevos contrastes ecográficos.OBJETIVO:Evaluar la eficacia y seguridad del hexafluoruro de azufre como agente de contraste ecográfico para el diagnóstico de fístula perianal comparándolo con el peróxido de hidrógeno diluido al 50%.DISEÑO:Estudio de superioridad doble ciego con cuatro visitas consecutivas realizando una ecografía sin contraste, ecografía potenciada con peróxido de hidrógeno, ecografía potenciada con hexafluoruro de azufre y exploración rectal en el quirófano (el estándar de oro). Las imágenes ecográficas fueron revisadas de forma independiente por tres cirujanos ecografistas expertos.AJUSTE:Estudio llevado a cabo en un único hospital universitario.PACIENTES:Se evaluaron datos de 176 pacientes.PRINCIPALES MEDIDAS DE RESULTADO:Se analizaron los datos demográficos y exploratorios y los hallazgos ecográficos relacionados con la ubicación del orificio interno de la fístula, descripción de los trayectos primario y secundario y la presencia de cavidades y defectos del esfínter. Se consideraron las complicaciones ocurridas antes y después de la administración del agente de contraste y la presencia de dolor medido mediante un puntaje.RESULTADOS:Se incluyeron 88 pacientes (hombres: 71,5%; edad media: 48,3 años). El 62,5% fueron tipo complejo y el 83,7% tipo transesfintérico. Las ecografías mejoradas con hexafluoruro de azufre demostraron mayor concordancia interobservador en la determinación de los trayectos secundarios (κ = 0,604) y la altura de la fístula anal (κ = 0,604) en comparación con otros métodos. Tanto la ecografía con peróxido de hidrógeno (90,91%) como la ecografía con hexafluoruro de azufre (89,77%) detectaron con mayor frecuencia el orificio interno que la ecografía sin contraste (62,5%) (p < 0,001), sin diferencias entre agentes de contraste (p = 0,810). La ecografía potenciada con hexafluoruro de azufre fue menos dolorosa que la ecografía potenciada con peróxido (p < 0,001).LIMITACIONES:La mayoría de los pacientes presentaron fístulas anales transesfintéricas.CONCLUSIONES:El hexafluoruro de azufre demostró ser comparable al peróxido de hidrógeno en la evaluación de los trayectos fistulosos y la identificación del orificio interno y con reducción significativa del dolor y malestar. Además, demostró mayor concordancia interobservador en la determinación de los trayectos secundarios y la altura de la fístula anal en comparación con otros métodos. (Traducción-Dr. Fidel Ruiz Healy ).

To use three-dimensional anorectal ultrasonography (3D-US) to evaluate the outcome of ligation of the intersphincteric fistula tract (LIFT) in patients with crypto-glandular transsphincteric fistula and describing the patterns of healing, failure, and recurrence rate.

After classifying the fistula and determining the length of the sphincter muscle to be transected, the patients were submitted to LIFT. The accuracy of pre- and postoperative 3D-US with 360° endoprobe (16 MHz) with automatic scanning and clinical findings was evaluated against surgical findings. Three outcomes were considered: healing, failure (persistent anal fistula through the original external opening or intersphincteric), and recurrence (reappearance of the anal fistula).

Sixty-three patients of both sexes were evaluated. The 3D-US assessment revealed primary healing in 50 (79.3%) patients, although in 6 (9.5%) cases healing was delayed and the cavity was without communication with the anal canal. The procedure failed in 9 (15.9%) and fistula recurred in 4 (6.3%), all of whom underwent a second surgery based on a new 3D-US, resulting in a 92.3% (12/13) healing rate on 3D-US.

A 3D-US was found to be useful in the preoperative assessment of fistulas by quantifying the percentage of muscle to be transected, and in the postoperative assessment by identifying healing, types of failure, and recurrence. The 3D-US was accurate and consistent with surgical findings.

Crohn disease perianal fistulas are associated with considerable morbidity and impaired quality of life. Nurses who specialize in inflammatory bowel disease (IBD) play a vital role in the management of Crohn disease perianal fistulas from diagnosis to long-term care; however, there is little evidence available to inform Crohn associated perianal fistula management strategies for nurses. This narrative review aims to provide IBD nurses with an up-to-date overview of Crohn perianal fistulas. It discusses the vital role IBD nurses play within the multidisciplinary team; the physical, social, and psychological impacts of Crohn perianal fistulas on patients; available treatment options; and how IBD nurses can support patients in their perianal fistula journey to enable optimum outcomes for patients. It also reviews diagnostic techniques and IBD nurses' involvement in Crohn perianal fistula diagnosis. While this article is aimed at IBD nurses, it is relevant to all nurses irrespective of their role (unit, clinic, community, and stoma) who interact with patients with Crohn perianal fistulas because awareness of the signs and symptoms of this condition will enable timely referrals and diagnosis.

CT and MR enterography are cross-sectional imaging examinations used in the assessment of inflammatory bowel disease. Consistent reporting and standardized nomenclature are important for clear communication with referring clinicians. Enterography has not only been used to depict inflammation in the small bowel, but it has also been used to quantify disease activity, assess distribution of disease, and detect complications including penetrating disease. This article reviews cross-sectional imaging findings in inflammatory bowel disease, including the current literature focusing on small bowel Crohn's disease and ulcerative colitis, with evidence-based guidelines on appropriate protocols and imaging procedures.

In this editorial we comment on the article by Pacheco et al published in a recent issue of the World Journal of Gastroenterology. We focus specifically on the burden of illness associated with perianal fistulizing Crohn's disease (PFCD) and the diagnostic and therapeutic challenges in the management of this condition. Evolving evidence has shifted the diagnostic framework for PFCD from anatomical classification systems, to one that is more nuanced and patient-focused to drive ongoing decision making. This editorial aims to reflect on these aspects to help clinicians face the challenge of PFCD in day-to-day clinical practice.

Most research on fistula-in-ano (FIA) is being done to improve surgical outcomes and reduce complications. Cyanoacrylate glue (CAG) is one of the promising options. We evaluated the efficacy and efficiency of CAG in the treatment of FIA.

A cohort of 30 patients were included who underwent treatment using CAG. Each patient followed up at one, three, and six months to evaluate improvement in pain, discomfort, and recurrence. Patients with recurrence were treated with fistulectomy.

The mean age of the cohort was 48.2±14.5 years, with a male-to-female ratio of 6:1, having four diabetic patients. Inter-sphincteric (16.54%) and trans-sphincteric (13.43%) fistulae were more common than extra-sphincteric (1.4%) fistula. The efficacy of CAG was 73%, and the procedure was found efficient with significant improvement in discomfort (p-value: 0.017). The recurrence rate was 27%, which occurred more in diabetic patients (p-value: 0.001) and trans-sphincteric fistula (p-value: 0.035).  Conclusion: The CAG application is a simple and safe daycare procedure. However, the incidence of discharge and relief in pain was significantly less, but it cannot be advised to every patient of FIA. A young patient without comorbidities and with inter-sphincteric low fistula can best be treated by this method.

Fistula in ano is a complex disease, and the treatment for it is still a big challenge for surgeons because of the high recurrence rate (7 %-50 %) and incontinence, and to minimize these complications numerous surgical interventions are emerging daily in the conventional system of medicine.

A 48- year- old male patient came with complaints of pus discharge from an external opening in the inner aspect of his right thigh, located about 22 to 25 cm away from the anal verge for the last 15 years and was diagnosed as long extrasphincteric fistula with intrarectal opening based on clinical and MRI findings. We successfully treated this case with a minimally invasive novel surgical technique, RetroGrade Probing and Application of KharaSutra and Division of the Fistulous Tract (RGPAKS- DFT).

Ksharasutra is a well-known method in the treatment of anal fistula for preserving continence and a low recurrence rate. Performing retrograde probing in every single case of anal fistula can address the involved anal gland under direct vision, which is essential for preventing recurrence and pairing retrograde probing with the division of the fistulous tract significantly reduces the treatment duration with minimal tissue loss.

In fistula surgery, successful treatment relies on identifying the internal opening and eradicating the involved anal glands. Based on the same principle, this rare and complex anal fistula was effectively treated with this RGPAKS-DFT, resulting in no recurrence and incontinence in two years of follow-up after complete recovery.

High horseshoe-shaped anal fistula (HHAF) is a complicated and challenging condition that presents considerable obstacles in treatment. We are presently investigating a novel surgical technique involving a combination of multi-incision and tube-dragging therapy, and laser closure (MITD-LaC) for the management of HHAF. Due to the current scarcity of rigorous evidence evaluating this approach, it is essential to perform a well-designed randomized controlled trial to compare the effectiveness of this new method with incision and thread-drawing therapy.

This trial is a prospective, randomized, controlled and interventional study. After preliminary screening of qualified outpatients, a total of 64 adult patients will be enrolled in the trial and randomly allocated to either the MITD-LaC group or the control group (n = 32 per group). These patients will receive either MITD-LaC or incision and thread-drawing therapy. The design aims to allow for a robust comparison between the two treatment modalities. The primary endpoint is the wound healing time, while secondary endpoints include postoperative anal pain at 1, 3, and 5 days (measured with visual analogue scale), fecal incontinence score within 30 days after operation (measured with Cleveland Clinic Florida incontinence score), and the occurrence of postoperative complications within 1 month after surgery, and quality of life up to six months postoperatively (evaluated by The Quality of Life in patients with Anal Fistula Questionnaire Score).

This study represents the first randomized controlled trial evaluating the short-term outcomes of MITD-LaC, thereby aiming to contribute high-quality evidence to guide clinical practice. Moreover, this trial incorporates comprehensive outcome measures assessing both subjective and objective dimensions. Because of this multidimensional assessment, MITD-LaC offers a promising potential for broader application in the treatment of HHAF. Consequently, obtaining more definitive and authoritative evidence through scientifically rigorous clinical trials is of utmost importance in further validating this treatment approach.

We have submitted the clinical study protocol to the Ethics Committee, and it has been approved under ethical approval number 2021-1036-111-01. The results of the trial will be disseminated through peer-reviewed academic journals and presentations at professional conferences.

ChiCTR2100053556.

Optimal treatment strategies for seton use in patients with Crohn's perianal fistulas (CPF) remain elusive. This systematic literature review aimed to summarize clinical, patient-reported, and healthcare resource utilization (HCRU) outcomes associated with seton use for symptomatic relief and treatment of complex CPF.

Electronic databases (MEDLINE, Embase, EBM Reviews, EconLit) were searched. Titles, abstracts, and relevant full texts were screened by 2 reviewers for inclusion using prespecified PICOS-T criteria. Articles published in English between January 1, 1980 and September 6, 2021 were included; animal/in vitro studies and case reports with <5 patients were excluded. Outcomes of interest included rates of complete response/remission and fistula recurrence in patients receiving seton with/without infliximab or biologics. Data were summarized using descriptive statistics.

Overall, 56 studies were included (full texts: n = 43; congress abstracts: n = 13). CPF and clinical outcome definitions were heterogeneous. Rates (range) of complete response/remission varied widely (seton: 13%-75%; seton + infliximab: 23%-100%; seton + biologics: 23%-59%) as did rates for fistula recurrence (seton: 4%-68%; seton + infliximab: 0%-50%; seton + biologics: 0%-17%). Rates of fistula-related reintervention, new fistula or abscess formation, and abscess recurrence were also varied; more consistency was observed regarding the use of patient-reported outcomes. Few studies reported outcomes from pediatric/adolescent patients or HCRU.

Optimal use of seton in patients with CPF remains unclear. International standardization of definitions for CPF and related clinical outcomes are required to permit data comparability and identify the most effective treatment strategies involving seton use in CPF.

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.