Randomized controlled trial of minimally invasive surgery using acellular dermal matrix for complex anorectal fistula

European Society of Coloproctology: Guidelines for diagnosis and treatment of cryptoglandular anal fistula

AIM

The primary aim of the European Society of Coloproctology (ESCP) Guideline Development Group (GDG) was to produce high-quality, evidence-based guidelines for the management of cryptoglandular anal fistula with input from a multidisciplinary group and using transparent, reproducible methodology.

METHODS

Previously published methodology in guideline development by the ESCP has been replicated in this project. The guideline development process followed the requirements of the AGREE-S tool kit. Six phases can be identified in the methodology. Phase one sets the scope of the guideline, which addresses the diagnostic and therapeutic management of perianal abscess and cryptoglandular anal fistula in adult patients presenting to secondary care. The target population for this guideline are healthcare practitioners in secondary care and patients interested in understanding the clinical evidence available for various surgical interventions for anal fistula. Phase two involved formulation of the GDG. The GDG consisted of 21 coloproctologists, three research fellows, a radiologist and a methodologist. Stakeholders were chosen for their clinical and academic involvement in the management of anal fistula as well as being representative of the geographical variation among the ESCP membership. Five patients were recruited from patient groups to review the draft guideline. These patients attended two virtual meetings to discuss the evidence and suggest amendments. In phase three, patient/population, intervention, comparison and outcomes questions were formulated by the GDG. The GDG ratified 250 questions and chose 45 for inclusion in the guideline. In phase four, critical and important outcomes were confirmed for inclusion. Important outcomes were pain and wound healing. Critical outcomes were fistula healing, fistula recurrence and incontinence. These outcomes formed part of the inclusion criteria for the literature search. In phase five, a literature search was performed of MEDLINE (Ovid), PubMed, Embase (Ovid) and the Cochrane Database of Systematic Reviews by eight teams of the GDG. Data were extracted and submitted for review by the GDG in a draft guideline. The most recent systematic reviews were prioritized for inclusion. Studies published since the most recent systematic review were included in our analysis by conducting a new meta-analysis using Review manager. In phase six, recommendations were formulated, using grading of recommendations, assessment, development, and evaluations, in three virtual meetings of the GDG.

RESULTS

In seven sections covering the diagnostic and therapeutic management of perianal abscess and cryptoglandular anal fistula, there are 42 recommendations.

CONCLUSION

This is an up-to-date international guideline on the management of cryptoglandular anal fistula using methodology prescribed by the AGREE enterprise.

Efficacy and safety of 13 surgical techniques for the treatment of complex anal fistula, non-Crohn CAF: a systematic review and network meta-analysis

BACKGROUND

Considering the difficulty of treating complex anal fistula (CAF), various surgical techniques exist in clinical work. However, none are ideal. Evidence on the efficacy and safety of different surgical treatments is scarce. The authors aimed to compare the outcomes of the 13 surgical techniques and tried to find the best surgical method for treating CAF.

MATERIALS AND METHODS

The authors searched worldwide databases, including Pubmed, Embase, Cochrane Library, Web of Science, CNKI, WanFang, VIP, and SinoMed, from inception to March 2023. All randomized controlled trials comparing the outcomes of 13 surgical techniques were included according to the PICO principles. The indicators of the cure rate, the recurrence rate, the complication rate, the operating time, the postoperative pain on day 1 (VAS), and the postoperative incontinence in month 1 (Wexner) were extracted and analyzed using STATA software 15.1, Review Manager 5.4, and GeMTC14.3.

RESULTS

Twenty-eight randomized controlled trials with a total of 2274 patients were included in the network meta-analysis. There was no statistically significant difference in the comparison among any surgical interventions in terms of the cure rate ( P >0.05 Table 2) and recurrence rate ( P >0.05 Table 3). However, in terms of complication rate, fistulectomy was lower than FPS (Median: 0.14; 95% CI: 0.02-0.70) or fistulotomy (Median: 0.09; 95% CI: 0.01-0.55), and fistulotomy was lower than EAFR (Median: 0.24; 95% CI: 0.05-0.84), LIFT (Median: 0.17; 95% CI: 0.02-0.66) or LIFT-EAFR (Median: 0.11; 95% CI: 0.01-0.69) ( P >0.05 Table 4). The surface estimated the advantages and disadvantages under the cumulative ranking (SUCRA). The ranking results indicated that fistulectomy might have the lowest complication rate (SUCRA=7.9%). Because the network results of the operating time, the postoperative pain, and the postoperative incontinence contained no closed loops, the results of their probability ranking could only be referenced, demonstrating that fistulectomy might have the shortest operating time (SUCRA=23.4%), video-assisted modified ligation of the intersphincteric fistula tract (VAMLIFT) might have the lowest postoperative pain on day 1 (VAS) (SUCRA=0.4%) and LIFT might have the lowest postoperative incontinence in month 1(Wexner) (SUCRA=16.2%).

CONCLUSION

Fistulectomy might have the lowest complication rate, which might be the relatively superior surgical technique for treating CAF.

Comparison of clinical outcomes of anal fistula plug and endoanal advancement flap repair treating the complex anal fistula: a systematic review and meta-analysis

Anal fistula (AF) is a common disease with high prevalence and surgical operations are effective treatments in clinical work. There exist many well-known surgical techniques treating complex anal fistula (CAF), however, none is ideal. To compare the superiority of Anal fistula plug (AFP) and Endoanal advancement flap repair (EAFR) for complex anal fistula. We searched worldwide databases including Pubmed, Embase, Cochrane Library, Web of Science, CNKI, WanFang, VIP, and SinoMed from their inception to March 2023. Studies comparing the outcomes of AFP and EAFR were included according to the PICO principles. The indicators of the healing rate, recurrence rate, wound infection rate, and complication rate, et al. were extracted and compared between different surgical methods. 5 RCTS and 7 non-RCTs were included in the meta-analysis with a total of 847 patients (341 patients conducted with AFP and 506 patients with EAFR). By combining the total effect of the 12 articles, we found that there was a statistical difference reporting the healing rate of AFP 48.3% and EAFR 64.4% treating the CAF (OR 0.68, 95% CI 0.30,1.55, P = 0.03), and EAFR has a better healing rate. However, there was no significant difference in terms of the recurrence rate (OR 1.68, 95% CI 0.80,3.54, P = 0.17), the wound infection rate (OR 1.82, 95% CI 0.95,3.52, P = 0.07), and the complication rate (OR 1.06, 95% CI 0.70,1.61, P = 0.77) either in the 12 articles or in the subgroup. The meta-analysis indicated that the EAFR was superior to AFP in terms of the healing rate treating the CAF, however, there were no significant differences between the two groups when it came to the recurrence rate, the wound infection rate, and the complication rate. EAFR might be one initial treatment for the complex cryptoglandular anal fistulas compared with AFP.

Efficacy of different surgical treatments for management of anal fistula: a network meta-analysis

PURPOSE

Currently, the anal fistula treatment which optimises healing and preserves bowel continence remains unclear. The aim of our study was to compare the relative efficacy of different surgical treatments for AF through a network meta-analysis.

METHODS

Systematic searches of MEDLINE, EMBASE and CENTRAL databases up to October 2022 identified randomised controlled trials (RCTs) comparing surgical treatments for anal fistulae. Fistulae were classified as simple (inter-sphincteric or low trans-sphincteric fistulae crossing less than 30% of the external anal sphincter (EAS)) and complex (high trans-sphincteric fistulae involving more than 30% of the EAS). Treatments evaluated in only one trial were excluded from the primary analyses to minimise bias. The primary outcomes were rates of success in achieving AF healing and bowel incontinence.

RESULTS

Fifty-two RCTs were included. Of the 14 treatments considered, there were no significant differences regarding short-term (6 months or less postoperatively) and long-term (more than 6 months postoperatively) success rates between any of the treatments in patients with both simple and complex anal fistula. Ligation of the inter-sphincteric fistula tract (LIFT) ranked best for minimising bowel incontinence in simple (99.1% of comparisons; 3 trials, n = 70 patients) and complex anal fistula (86.2% of comparisons; 3 trials, n = 102 patients).

CONCLUSIONS

There is insufficient evidence in existing RCTs to recommend one treatment over another regarding their short and long-term efficacy in successfully facilitating healing of both simple and complex anal fistulae. However, LIFT appears to be associated with the least impairment of bowel continence, irrespective of AF classification.

Long-term outcomes of an acellular dermal matrix for the treatment of complex cryptoglandular anal fistula: a pilot study

Backgound

Effective, standardized treatments for complex anal fistula (CAF) still represent a clinical challenge. Emerging procedures attempted to achieve the healing rates of fistulotomy whilst preserving sphincter function. Acellular dermal matrix (ADM) used as a plug inserted through the fistulous tract is among newer treatment options. Varying success rates have been reported, most with short-term follow-up. The aim of this study was to report the long-term results of ADM-plug for CAF.

Methods

Retrospective analysis of a prospective database of patients treated with CAF. All consecutive patients presenting at two tertiary centers (Vall d’Hebron University Hospital and Bellvitge University Hospital, Barcelona, Spain) between November 2015 and March 2019 with a single, cryptoglandular CAF were evaluated for treatment with an ADM-plug were included. The primary endpoint was absence of discharge at clinical examination at 12 month follow-up.

Results

Twenty-two patients were included [7 women and 15 men, median age 56 (33–74) years]. Most patients had high transsphincteric fistulas (63.6%). The median follow-up was 42 (21–53) months. The 12 month success rate was 68.2%, with an overall healing rate of 59.1%. 77.8% of recurrences occurred within 12 months from surgery. One plug extrusion was observed. No major complications or mortality occurred during the follow-up. Patients did not report any worsening of fecal continence.

Conclusions

This pilot study showed that more than half of patients with CAF could benefit from ADM-plug placement, preserving continence. A minimum follow-up of 12 months is recommended, because most recurrences occur during the first year.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10151-022-02593-1.

Video-assisted anal fistula treatment combined with anal fistula plug for treatment of horseshoe anal fistula

Objective

Horseshoe anal fistula is a common anorectal disease, and there is no standard procedure for its treatment. In this study, we performed a modified surgical procedure for the treatment of horseshoe anal fistula and investigated its efficacy and adverse effects.

Methods

We retrospectively analyzed the outcomes of video-assisted anal fistula treatment combined with an anal fistula plug (VAAFT-Plug) in 26 patients with a horseshoe anal fistula. The follow-up period ranged from 6 to 18 months. Preoperative and postoperative data were collected to analyze the cure rate, anal sphincter function, and incidence of complications.

Results

The surgeries were successfully performed in all patients, 23 of whom were cured (effective cure rate of 88.46%). Three patients developed recurrence and were cured after traditional surgery. No patients developed severe complications or postoperative anal incontinence. The VAAFT-Plug protocol was performed with a small incision in the fistula that subsequently promoted fistula healing and preserved sphincter function.

Conclusion

Although randomized controlled trials will be needed to fully validate these findings, our results suggest that VAAFT-Plug represents a promising treatment strategy for horseshoe anal fistulas. This technique preserves normal anal function and achieves satisfactory outcomes in most patients.

Safety of Allogeneic Adipose Tissue-Derived Mesenchymal Stem Cells for the Treatment of Complex Perianal Fistulas Not Associated With Crohn's Disease: A Phase I Clinical Trial

BACKGROUND

Anal fistula treatment aims to eradicate the fistula, preserve the sphincter, prevent recurrence, and allow an early return to daily activities for the patient. Because of the difficulty of achieving these goals, stem cell-based therapy has emerged for the treatment of complex perianal fistula with promising results.

OBJECTIVE

The objective of this study was to evaluate the safety of allogeneic mesenchymal stem cells in the treatment of complex anal fistula in patients without Crohn's disease.

DESIGN

This was a prospective nonrandomized phase I clinical trial.

SETTINGS

This study was conducted at a second-level hospital.

PATIENTS

Twenty consecutive patients diagnosed with a complex fistula were included.

INTERVENTIONS

All patients received 40 × 106 allogeneic mesenchymal stem cells. In patients with 2 tracts, 20 × 106 stem cells were applied on each tract.

MAIN OUTCOME MEASURES

The patients were discharged 24 hours after the procedure and were evaluated at 1, 2, 4, 8, 16, and 24 weeks after the application. The long-term follow-up was performed 1 year after the procedure.

RESULTS

The procedure was performed in a total of 20 patients from October 1, 2016, to October 31, 2017; 1 patient was eliminated from the final data analysis. No adverse effects were reported within the first 24 hours, and all the patients were discharged asymptomatic. Three patients (15%) presented with perianal abscess. In 1 patient, the abscess appeared at the fourth week, and, in the other 2 patients, the abscess was diagnosed at week 8. Complete closure was achieved in 13 (69%) patients.

LIMITATIONS

This was a nonrandomized controlled trial.

CONCLUSION

The use of allogeneic mesenchymal stem cells as a treatment is a safe option for the management of complex perianal fistula not associated with Crohn's disease. See Video Abstract at http://links.lww.com/DCR/B443.

SEGURIDAD DE LAS CLULAS MADRE MESENQUIMALES ALOGNICAS DERIVADAS DEL TEJIDO ADIPOSO PARA EL TRATAMIENTO DE FSTULAS PERIANALES COMPLEJAS NO ASOCIADAS CON LA ENFERMEDAD DE CROHN ENSAYO CLNICO DE FASE I

ANTECEDENTES:El tratamiento de la fístula anal tiene como objetivo erradicar la fístula, preservar el esfínter, prevenir la recurrencia y permitir un retorno temprano a las actividades diarias del paciente. Debido a la dificultad de alcanzar estos objetivos, ha surgido una terapia basada en células madre para el tratamiento de la fístula perianal compleja con resultados prometedores.OBJETIVO:El objetivo de este estudio fue evaluar la seguridad de las células madre mesenquimales alogénicas en el tratamiento de la fístula anal compleja en pacientes sin enfermedad de Crohn.DISEÑO:Este fue un ensayo clínico prospectivo no aleatorizado de fase I.AMBIENTE:Este estudio se realizó en un hospital de segundo nivel.PACIENTES:Veinte pacientes consecutivos diagnosticados de fístula compleja.INTERVENCIONES:Todos los pacientes recibieron 40 x 106 células madre mesenquimales alogénicas, en pacientes con dos tractos, se aplicaron 20 x 106 células madre en cada tracto.PRINCIPALES MEDIDAS DE RESULTADO:Los pacientes fueron dados de alta 24 horas después del procedimiento y fueron evaluados 1, 2, 4, 8, 16, 24 semanas después de la aplicación. El seguimiento a largo plazo se realizó un año después del procedimiento.RESULTADOS:El procedimiento se realizó en un total de 20 pacientes desde el 1 de octubre de 2016 al 31 de octubre de 2017; un paciente fue eliminado del análisis de datos final. No se informaron efectos adversos en las primeras 24 horas, todos los pacientes fueron dados de alta asintomáticos. Tres pacientes (15%) presentaron absceso perianal. En un paciente, el absceso apareció a la cuarta semana y en los otros dos pacientes el absceso se diagnosticó en la octava semana. El cierre completo se logró en 13 (69%) de los pacientes.LIMITACIONES:Este fue un ensayo controlado no aleatorio.CONCLUSIÓN:El uso de células madre mesenquimales alogénicas como tratamiento es una opción segura para el manejo de la fístula perianal compleja no asociada con la enfermedad de Crohn. Consulte Video Resumen en http://links.lww.com/DCR/B443.

Evaluation and management of perianal abscess and anal fistula: SICCR position statement

Perianal sepsis is a common condition ranging from acute abscess to chronic anal fistula. In most cases, the source is considered to be a non-specific cryptoglandular infection starting from the intersphincteric space. Surgery is the main treatment and several procedures have been developed, but the risks of recurrence and of impairment of continence still seem to be an unresolved issue. This statement reviews the pertinent literature and provides evidence-based recommendations to improve individualized management of patients.

Anal fistula plug vs rectal advancement flap for the treatment of complex cryptoglandular anal fistulas: a systematic review and meta-analysis of studies with long-term follow-up

AIM

The aim was to compare the effectiveness of the anal fistula plug (AFP) with the rectal advancement flap (RAF) for complex cryptoglandular anal fistulas.

METHODS

We conducted a literature search to identify relevant available articles published without language restriction from Embase and PubMed databases and the Cochrane Library. Studies comparing outcomes with the AFP vs RAF for complex cryptoglandular anal fistulas were eligible for inclusion.

RESULTS

A total of 11 articles with 810 patients were included in this meta-analysis. Four RCTs and one observational clinical study provided long-term follow-up. The pooled analysis of all 11 studies indicated that there was no significant difference between the AFP and RAF in terms of healing rate, recurrence rate and incidence of fistula complications. However, the pooled results of studies with long-term follow-up revealed that the RAF group had a significantly higher healing rate (OR 0.32, 95% CI 0.13, 0.78, P = 0.01) and lower recurrence rate (OR 4.45, 95% CI 1.45, 13.65, P = 0.009) than the AFP group.

CONCLUSIONS

For the treatment of complex cryptoglandular anal fistulas, the RAF was superior to the AFP in terms of healing and recurrence rate after pooling of randomized controlled trials with long-term follow-up, even though a comparison based on the pooling of all studies showed no significant difference.

The treatment of anal fistula: second ACPGBI Position Statement - 2018

It is over 10 years since the first ACPGBI Position Statement on the management of anal fistula was published in 2007. This second edition is the result of scrutiny of the literature published during this time; it updates the original Position Statement and reviews the published evidence surrounding treatments for anal fistula that have been developed since the original publication.

The best surgical strategy for anal fistula based on a network meta-analysis

OBJECTIVE

To determine a superior surgical treatment for anal fistula through a network meta-analysis and to provide the best direction for development in this field.

METHODS

We conducted a systematic literature search of the PubMed, Embase and Cochrane Library databases and extracted data from randomized controlled trials, which compared healing time, incontinence and recurrence associated with surgical strategies for anal fistula. A network meta-analysis was conducted using ADDIS software by evaluating the 3 parameters. Cumulative probability values were utilized to rank the strategies under examination. Inconsistencies were also tested using node-splitting models.

RESULTS

Twenty articles with 1663 patients were included. Fistulotomy plus marsupialisation had the shortest healing time (P = 0.69). Seton placement was the best procedure to avoid postoperative incontinence (P = 0.66). Fistulectomy exhibited the lowest recurrence rate (Probability P = 0.40). In general, fistulotomy plus marsupialisation and surgical ligation plus biomaterial plugging revealed superior clinical efficacy. Node-splitting model testing revealed that no significant inconsistency existed in this research.

CONCLUSIONS

Fistulotomy plus marsupialisation exhibited preliminary superior surgical utility for anal fistula. Additionally, combination of surgical treatment with biomaterials may provide better clinical efficacy. These techniques may warrant consideration for future development in this field.

A novel model of acellular dermal matrix plug for anal fistula treatment. Report of a case and surgical consideration based on first utility in Poland

Anal fistula (AF) is a pathological connection between anus and skin in its surroundings. The main reason for the formation of anal fistula is a bacterial infection of the glands within the anal crypts. One of the modern techniques for the treatment of fistulas that do not interfere with the sphincters consists in implantation of a plug made from collagen material. We are presenting the first Polish experience with a new model of biomaterial plug for the treatment of anal fistula. We also point out key elements of the procedure (both preoperative and intraoperative) associated with this method. In the authors' opinion, the method is simple, safe and reproducible. Innovative shape of the plug minimizes the risk of its migration and rotation. It also perfectly blends with and adapts to the course and shape of the fistula canal, allowing it to become incorporated and overgrown with tissue in the fistula canal. The relatively short operation time, minor postoperative pain and faster convalescence are with no doubt additional advantages of the method. Long-term observation involving more patients is essential for evaluation of the efficacy of the treatment of fistulas with the new type of plug.

Rectal advancement flap for the treatment of complex cryptoglandular anal fistulas: a systematic review and meta-analysis

PURPOSE

Rectal advancement flap is an accepted approach for treating complex fistula-in-ano. However, a diversity of technical modifications have been described. The aim of this study was to evaluate recurrence and fecal continence rates after performing rectal advancement flaps depending upon flap thickness (full-thickness, partial-thickness, or mucosal flaps) and treatment of the fistulous tract (core-out or curettage).

METHODS

Medline (PubMed, Ovid), the Cochrane Library database, and ClinicalTrials.gov were searched. Studies that involved patients with complex cryptoglandular fistulas who had been treated with rectal advancement flaps were included. The outcomes measured were recurrence and fecal continence. All of the statistical analyses were performed using Comprehensive Meta-Analysis software. A fixed model was used if there was no evidence of heterogeneity; otherwise, a random effects model was used.

RESULTS

Twenty-six studies were included (1655 patients). The pooled rate of recurrence was 21%. Full-thickness flaps showed the best results concerning recurrence (7.4%), partial flaps revealed 19% and mucosal flaps 30.1%. Core-out and curettage had a similar recurrence (19 vs 21%). Regarding anal incontinence, the pooled rate was 13.3%. Mucosal- and partial-thickness flaps showed similar rates (9.3 vs 10.2%), while full-thickness flaps disturbed it in 20.4%. Most of these alterations were minor symptoms. Otherwise, core-out and curettage showed similar rates (14.3 vs 12%).

CONCLUSIONS

1. Full-thickness rectal advancement flaps offer better results regarding the recurrence than mucosal or partial flaps. 2. All flaps cause some incontinence, which increases with the thickness of the flap. 3. The results did not suggest differences in recurrence and incontinence between core-out and curettage.

Factibility and security study of the PICS-AF™ plug for the treatment of cryptoglandular anal fistula

INTRODUCTION

The PICS-AF™ (Curaseal Inc.) device is a new plug made of collagen that has a retention system in the internal orifice. This pilot study was designed to assess both the feasibility and safety of this plug in the treatment of trans-sphincteric anal fístulas.

METHODS

A total of 44 patients (34 men), with a mean age of 54.68±7.3, with trans-sphincteric anal fístulas were included in the study; 34 of them were analyzed. All patients were examined according to a strict preoperative protocol and until 6 months after surgery. The feasibility of the procedure and the adverse events were analyzed.

RESULTS

Finally, 34 patients were operated on, and in 30 of them the plug was used. Therefore, the feasibility was calculated at 88%. There was a total of 16 adverse events, 4recorded as not related (3 mild and one moderate) and 12 related to the procedure or to the device implanted. Of these, 5were mild, 5moderate and 2severe. The majority of the events reported were related to proctalgia (4 patients) or infection at the implant site (4 patients).

CONCLUSIONS

The present study indicates that the new collagen plug can be placed effectively and with an acceptable complication rate.

Experimental porcine model of complex fistula-in-ano

AIM

To establish and evaluate an experimental porcine model of fistula-in-ano.

METHODS

Twelve healthy pigs were randomly divided into two groups. Under general anesthesia, the experimental group underwent rubber band ligation surgery, and the control group underwent an artificial damage technique. Clinical magnetic resonance imaging (MRI) and histopathological evaluation were performed on the 38^th d and 48^th d after surgery in both groups, respectively.

RESULTS

There were no significant differences between the experimental group and the control group in general characteristics such as body weight, gender, and the number of fistula (P > 0.05). In the experimental group, 15 fistulas were confirmed clinically, 13 complex fistulas were confirmed by MRI, and 11 complex fistulas were confirmed by histopathology. The success rate in the porcine complex fistula model establishment was 83.33%. Among the 18 fistulas in the control group, 5 fistulas were confirmed clinically, 4 complex fistulas were confirmed by MRI, and 3 fistulas were confirmed by histopathology. The success rate in the porcine fistula model establishment was 27.78%. Thus, the success rate of the rubber band ligation group was significantly higher than the control group (P < 0.05).

CONCLUSION

Rubber band ligation is a stable and reliable method to establish complex fistula-in-ano models. Large animal models of complex anal fistulas can be used for the diagnosis and treatment of anal fistulas.

Adoption and success rates of perineal procedures for fistula-in-ano: a systematic review

AIM

Several sphincter-preserving techniques have been described with extremely encouraging initial reports. However, more recent studies have failed to confirm the positive early results. We evaluate the adoption and success rates of advancement flap procedures (AFP), fibrin glue sealant (FGS), anal collagen plug (ACP) and ligation of intersphincteric fistula tract (LIFT) procedures based on their evolution in time for the management of anal fistula.

METHOD

A PubMed search from 1992 to 2015. An assessment of adoption, duration of study and success rate was undertaken.

RESULTS

We found 133 studies (5604 patients): AFP (40 studies, 2333 patients), FGS (31 studies, 871 patients), LIFT (19 studies, 759 patients), ACP (43 studies, 1641 patients). Success rates ranged from 0% to 100%. Study duration was significantly associated with success rates in AFP (P = 0.01) and FGS (P = 0.02) but not in LIFT or ACP. The duration of use of individual procedures since first publication was associated with success rate only in AFP (P = 0.027). There were no statistically significant differences in success rates relative to the number of the patients included in each study.

CONCLUSION

Success and adoption rates tend to decrease with time. Differences in patient selection, duration of follow-up, length of availability of the individual procedure and heterogeneity of treatment protocols contribute to the diverse results in the literature. Differences in success rates over time were evident, suggesting that both international trials and global best practice consensus are desirable. Further prospective randomized controlled trials with homogeneity and clear objective parameters would be needed to substantiate these findings.

A systematic review of new treatments for cryptoglandular fistula in ano

AIM

In 2007 the ACPGBI published a position statement on the management of cryptoglandular fistula in ano. Over the last seven years a number of new treatments have been developed and the aim of this systematic review was to assess their effectiveness.

METHOD

A systematic review of all English language literature relevant to novel treatment strategies for cryptoglandular fistula in ano, published between 1 January 2007 and 31 Dec 2014 was carried out using MEDLINE (PubMed and Ovid), EMBASE (Ovid) and the Cochrane Library of Systematic Reviews/Controlled Trials for relevant literature. Technical notes, commentaries, letters and meeting abstracts were excluded. The different treatments were assessed with regards to fistula closure rate in relation to length of follow up and reported complications.

RESULTS

Seventy potential articles published between 1 January 2007 and 31 December 2014 were identified from the initial literature search. Twenty-one articles were included for final analysis although only two were randomized controlled trials, the remainder being retrospective or prospective series.

CONCLUSION

This systematic review has demonstrated that whilst there have been technological advances to treat complex cryptoglandular fistula in ano, these are in an early stage of evolution and although early results were promising they are difficult to reproduce. Longer follow up data is not currently available and these treatments should not be introduced without further evidence.

Fistula tract curettage and the use of biological dermal plugs improve high transsphincteric fistula healing in an animal model

PURPOSE

The treatment of high transsphincteric fistula is a complex procedure, which may be associated with the risk of recurrence and fecal incontinence. In this study, we used an animal model to compare different types of sphincter-preserving treatments for transsphincteric fistula.

METHODS

Sixteen female New Zealand rabbits, weighing 2.8-4.8 kg underwent a surgical creation of high transsphincteric fistula. After 6 weeks, magnetic resonance imaging (MRI) was performed in order to confirm fistula formation and measure the fistula diameter. The rabbits were divided into three groups. Group 1 received no plug treatment (control). Autologous dermal graft and acellular dermal matrix were used as a plug in groups 2 and 3, respectively. Five weeks after treatment, fistula tract healing was determined by measuring the largest fistula diameter with MRI. All rabbits were euthanized and the anorectum excised en bloc for histopathological examination.

RESULTS

According to the MRI findings, all groups showed significant healing after the treatment (p < 0.05). The healing rate of fistula diameters after treatment was 40, 66, and 29% in the control, dermal graft, and acellular dermal matrix groups, respectively. In terms of negative healing parameters such as neutrophil, eosinophil, lymphocyte, and plasmocyte accumulation, dermal graft and acellular dermal matrix groups showed significantly lower results than those in the control group (p < 0.05).

CONCLUSION

According to MRI and histopathological results, fistula tract curettage and fistula orifice closure improved transsphincteric anal fistula healing. Additionally, in this study, plug treatment favoring autologous dermal graft resulted in better healing.

Therapeutic management of complex anal fistulas by installing a nitinol closure clip: study protocol of a multicentric randomised controlled trial--FISCLOSE

INTRODUCTION

Complex anal fistulas are responsible for pain, faecal incontinence and impaired quality of life. The rectal mucosa advancement flap (RMAF) procedure to cover the internal opening of the fistula remains a strategy of choice. However, a new procedure for closing anal fistulas is now available with the use of a nitinol closure clip (OTSC Proctology, OVESCO), which should ensure a better healing rate. This procedure is currently becoming more widespread, though without robust scientific validation, and it is therefore essential to carry out a prospective evaluation in order to determine the efficacy and safety of this new medical device for complex anal fistulas.

METHODS AND ANALYSIS

The FISCLOSE trial is aimed at evaluating the efficacy and safety of a nitinol closure clip compared to the RMAF procedure for the management of complex anal fistulas. This trial is a prospective, randomised, controlled, single-blind, bicentre and interventional study. Patients (n=46 per group) will be randomly assigned for management with either a closure clip or RMAF. The main objectives are to improve the healing rate of the anal fistula, lessen the postoperative pain and faecal incontinency, enhance the quality of life, and lower the number of reinterventions and therapeutic management costs. The primary outcome is the proportion of patients with a healed fistula at 3 months. The secondary outcomes are anal fistula healing (6 and 12 months), proctological pain (visual analogue scale), the faecal incontinence score (Jorge and Wexner questionnaire), digestive disorders and quality of life (Gastrointestinal Quality of Life Index and Euroqol EQ5D-3 L) up to 1 year.

ETHICS AND DISSEMINATION

The study was approved by an independent medical ethics committee 1 (IRB00008526, CPP Sud-Est 6, Clermont-Ferrand, France) and registered by the competent French authority (ANSM, Saint Denis, France). The results will be disseminated in a peer-reviewed journal and presented at international congresses.

TRIAL REGISTRATION NUMBER

NCT02336867; pre-result.

Treatment of Fistula-In-Ano with Fistula Plug - a Review Under Special Consideration of the Technique

Introduction

In a recent Cochrane review, the authors concluded that there is an urgent need for well-powered, well-conducted randomized controlled trials comparing various modes of treatment of fistula-in-ano. Ten randomized controlled trials were available for analyses: There were no significant differences in recurrence rates or incontinence rates in any of the studied comparisons. The following article reviews the studies available for treatment of fistula-in-ano with a fistula plug with special attention paid to the technique.

Material and Methods

PubMed, Medline, Embase, and the Cochrane medical database were searched up to July 2015. Sixty-four articles were relevant for this review.

Results

Healing rates of 50–60% can be expected for treatment of complex anal fistula with a fistula plug, with a plug-extrusion rate of 10–20%. Such results can be achieved not only with plugs made of porcine intestinal submucosa but also those made of other biological or synthetic bioabsorbable mesh materials. Important technical steps are firm suturing of the head of the plug in the primary opening and wide drainage of the secondary opening.

Discussion

Treatment of a complex fistula-in-ano with a fistula plug is an option with a success rate of 50–60% with low complication rate. Further improvements in technique and better studies are needed.

Tissue-Engineered External Anal Sphincter Using Autologous Myogenic Satellite Cells and Extracellular Matrix: Functional and Histological Studies

The aim of the present study was to demonstrate the regaining histological characteristics of bioengineered external anal sphincters (EAS) in rabbit fecal incontinence model. The EAS of 16 rabbits were resected and decellularized. The decellularized scaffolds were transplanted to the terminal rectum following a period of 6 months of fecal incontinency (5 days after sterilization). The rabbits were divided into two groups: in group 1 (n = 8), myogenic satellite cells were injected into the transplanted sphincters. In group 2 (n = 8), the transplanted scaffolds remained in situ without cellular injection. The histological evaluation was performed with desmin, myosin, smooth muscle actin, CD31, and CD34 at 3-month intervals. The rabbits were followed for 2 years. Electromyography (EMG) with needle and electrical stimulation, pudendal and muscle electrical stimulation were also performed after 2 years of transplantation. At the time of biopsy, no evidence of inflammation or rejection was observed and the transplanted EAS appeared histologically and anatomically normal. The immunohistochemistry staining validated that the histological features of EAS was more satisfactory in group 1 in short-term follow-up. However, no statistically significant difference was detected between two groups in long-term follow-ups (p value > 0.05). In both groups, grafted EAS contracted in response to electrical signals delivered to the muscle and the pudendal nerve. However, more signals were detected in group 1 in EMG evaluation. In conclusion, bioengineered EAS with myogenic satellite cells can gain more satisfactory histological outcomes in short-term follow-ups with better muscle electrical stimulation outcomes.

Evaluation and management of perianal abscess and anal fistula: a consensus statement developed by the Italian Society of Colorectal Surgery (SICCR)

Perianal sepsis is a common condition ranging from acute abscess to chronic fistula formation. In most cases, the source is considered to be a non-specific cryptoglandular infection starting from the intersphincteric space. The key to successful treatment is the eradication of the primary track. As surgery may lead to a disturbance of continence, several sphincter-preserving techniques have been developed. This consensus statement examines the pertinent literature and provides evidence-based recommendations to improve individualized management of patients.

Systematic review and meta-analysis of surgical interventions for high cryptoglandular perianal fistula

PURPOSE

Perianal fistulas, and specifically high perianal fistulas, remain a surgical treatment challenge. Many techniques have, and still are, being developed to improve outcome after surgery. A systematic review and meta-analysis was performed for surgical treatments for high cryptoglandular perianal fistulas.

METHODS

Medline (Pubmed, Ovid), Embase and The Cochrane Library databases were searched for relevant randomized controlled trials on surgical treatments for high cryptoglandular perianal fistulas. Two independent reviewers selected articles for inclusion based on title, abstract and outcomes described. The main outcome measurement was the recurrence/healing rate. Secondary outcomes were continence status, quality of life and complications.

RESULTS

The number of randomized trials available was low. Fourteen studies could be included in the review. A meta-analysis could only be performed for the mucosa advancement flap versus the fistula plug, and did not show a result in favour of either technique in recurrence or complication rate. The mucosa advancement flap was the most investigated technique, but did not show an advantage over any other technique. Other techniques identified in randomized studies were seton treatment, medicated seton treatment, fibrin glue, autologous stem cells, island flap anoplasty, rectal wall advancement flap, ligation of intersphincteric fistula tract, sphincter reconstruction, sphincter-preserving seton and techniques combined with antibiotics. None of these techniques seem superior to each other.

CONCLUSIONS

The best surgical treatment for high cryptoglandular perianal fistulas could not be identified. More randomized controlled trials are needed to find the best treatment. The mucosa advancement flap is the most investigated technique available.

Biomaterials in the treatment of anal fistula: hope or hype?

Anal fistula (AF) presents a chronic problem for patients and colorectal surgeons alike. Surgical treatment may result in impairment of continence and long-term risk of recurrence. Treatment options for AFs vary according to their location and complexity. The ideal approach should result in low recurrence rates and minimal impact on continence. New technical approaches involving biologically derived products such as biological mesh, fibrin glue, fistula plug, and stem cells have been applied in the treatment of AF to improve outcomes and decrease recurrence rates and the risk of fecal incontinence. In this review, we will highlight the current evidence and describe our personal experience with these novel approaches.

The treatment of anal fistulas with biologically derived products: is innovation better than conventional surgical treatment? An update

New technical approaches involving biologically derived products have been applied in the treatment for anal fistulas in order to avoid the risk of fecal incontinence. The aim of this review was to evaluate the scientific evidence present in the literature regarding these techniques. Trials comparing surgery (fistulotomy, advancement mucosal flap closure and placement of seton) versus fibrin glue, fistula plug or acellular dermal matrix were considered. In fibrin glue versus traditional surgical treatment the healing rate was higher in the surgery group, and the recurrence rate was lower in the traditional surgery group, but these results were not statistically relevant. In acellular dermal matrix (ADM) versus traditional surgical treatment the recurrence rate of fistulas was significantly lower in the ADM group, but non-significant differences were recorded in incontinence and anal deformity. Our review shows that there are no significant advantages of the new techniques involving biologically derived products. Further randomized controlled trials are needed.

Novel biological strategies in the management of anal fistula

BACKGROUND

The mostly widely studied biomaterials for the sphincter sparing treatment of anal fistulas are fibrin glue and the anal fistula plug (AFP). However their overall mean clinical success is only 50-60%. As the understanding of the pathology of anal fistula, wound healing and the host response to materials has improved, so new biological sphincter-sparing strategies have been developed. The aim of this review is to assess the safety and efficacy of these novel techniques.

METHOD

PubMed, the Cochrane database and EMBASE were independently searched. All studies that investigated the potential of a biomaterial (defined as any synthetic or biologically derived substance in contact with host tissue) to augment the healing of anal fistula without sphincter division were included. Studies solely describing the role of fibrin glue or an AFP were excluded. Data extraction included type of material, fistula aetiology, treatment of the primary tract, fistula healing, incontinence, duration of follow-up and any specific complications. Systematic quality assessment of the included articles was performed.

RESULTS

Twenty-three articles were finally selected for review. These included a variety of biological and synthetic systems that were employed to deliver selected components of the extracellular matrix, growth factors, cytokines, stem cells or drugs to the fistula tract.

CONCLUSION

To date no study matches fistulotomy with regard to long-term fistula eradication rate. This is probably due to implant extrusion, inadequate track preparation or an unsuitable material. Future techniques need to address all these issues to ensure success. Success should be validated by MRI or long-term follow-up.

Anal fistula plug vs mucosa advancement flap in complex fistula-in-ano: A meta-analysis

AIM: To investigate the efficacy of the anal fistula plug (AFP) compared to the mucosa advancement flap (MAF), considered the best procedure for patients with a complex anal fistula.

METHODS: The literature search included PubMed, EMBASE, Cochrane Library and OVID original studies on the topic of AFP compared to MAF for complex fistula-in-ano that had a deadline for publication by April 2011. Randomized controlled trials, controlled clinical trials and prospective cohort studies were included in the review. After information collection, a meta-analysis was performed using data on overall success rates as well as incidence of incontinence and morbidity. The quality of postoperative life was also included with the clinical results.

RESULTS: Six studies involving 408 patients (AFP = 167, MAF = 241) were included in the meta-analysis. The differences in the overall success rates and incidence of fistula recurrence were not statistically significant between the AFP and MAF [risk difference (RD) = -0.12, 95%CI: -0.39 - 0.14; RD = 0.13; 95%CI: -0.18 - 0.43, respectively]. However, for the AFP, the risk of postoperative impaired continence was lower (RD = -0.08, 95%CI: -0.15 - -0.02) as was the incidence of other complications (RD = -0.06, 95%CI: -0.11 - -0.00). The postoperative quality of life, for patients treated using the AFP was superior to that of the MAF patients. Patients treated with the AFP had less persistent pain of a shorter duration and the healing time of the fistula and hospital stay were also reduced.

CONCLUSION: The AFP is an effective procedure for patients with a complex anal fistula; it has the same success rate but a lower risk of complications than the MAF and may also be associated with an improved postoperative quality of life. Additional evidence is needed to confirm these findings.

Application of acellular dermal matrix in reconstruction of oral mucosal defects in 36 cases

PURPOSE

Artificial grafts have been investigated for use in the repair of oral mucosal defects. The aim of this retrospective study was to present the outcomes of the use of acellular dermal matrix (ADM) grafts to repair oral mucosal defects.

MATERIALS AND METHODS

Data from 36 patients with oral mucosal defects reconstructed with ADM grafts from 2003 through 2009 were reviewed. All patients were followed-up for at least 6 months to observe the graft repair, wound-healing time, contracture, color, infection, pain, immunologic reaction, texture of the graft, and clinical course. Graft success was defined as the ADM graft being replaced by new mucosa-like tissue and the oral mucosal defect being covered with the new mucosa-like tissue. Any evidence of incomplete graft re-epithelialization or graft sloughing was considered a graft failure (complete or incomplete).

RESULTS

Of the 36 cases, 34 grafts (94.4%) were successfully replaced with new mucosa-like tissues and only 2 grafts (5.6%) failed. No complaints such as pain, immunologic reaction, or infection were observed during the follow-up. Mild graft contraction occurred in 7 patients with lip or buccal defects, especially at approximately 3 to 5 weeks after the reconstructive surgery.

CONCLUSIONS

The ADM grafts for oral mucosal defects were safe and effective. The present data support the clinical application of ADM grafts in reconstructing oral mucosal defects caused by various oral diseases.

Long-term outcomes of human acellular dermal matrix plug in closure of complex anal fistulas with a single tract

BACKGROUND

Bioprosthetic plugs represent a promising technique for the treatment of anal fistula simple because they allow simple and repeatable application, preservation of sphincter integrity, minimal patient discomfort, and subsequent surgical options if needed. However, success rates vary widely.

OBJECTIVE

The aim of this study was to assess long-term outcome in patients treated with an acellular dermal matrix plug for closure of complex single-tract anal fistulas.

DESIGN

This was a retrospective analysis of a prospective database.

SETTING

The study was conducted at a university hospital in Beijing, People's Republic of China.

PATIENTS

The study population comprised 114 patients treated between January 2007 and May 2010 for complex high transsphincteric anal fistula with a single tract.

INTERVENTION

Fistulas were treated with an acellular dermal matrix plug derived from donated human skin.

MAIN OUTCOME MEASURES

The main outcome measures were fistula closure rate and postoperative incontinence (Wexner scores).

RESULTS

No mortality or major complications were observed. The overall success rate was 54.4% (62/114), with a median follow-up of 19.5 (range, 11-46) months. Of the 52 patients with plug failure, 11 (21%) had plug extrusion and 9 (17%) had sepsis. Most plug failures occurred within 30 days, with only 1 plug failure occurring 6 months after surgery. On multiple logistic regression analysis, smoking (P < .001), long distance between external opening (P < .001), and performance of the operation by a nonexpert surgeon (P = .018) were significantly associated with plug failure. Of 40 patients who underwent cutting seton placement after plug failure, 33 (82.5%) reported a successful outcome. However, the rate of incontinence 6 months after seton placement was 75% (30/40), whereas the rate in the overall study population 6 months after insertion of the ADM plug was 1.75% (2/114; P < .001).

LIMITATIONS

This study was limited by its retrospective nature.

CONCLUSIONS

Given the low morbidity and relative simplicity of the procedure, we suggest that an acellular dermal matrix plug is a reasonable option for closure of complex anal fistulas with a single tract.

Why do we have to review our experience in managing cases with idiopathic fistula-in-ano regularly?

“Why do we have to review our experience in managing idiopathic fistula-in-ano regularly?” In order to answer this apparently simple question, we reviewed our clinical and surgical cases and most important relevant literature to find a rational and scientific answer. It would appear that whatever method you adopt in fistula management, there is a price to pay regarding either rate of recurrence (higher with conservative methods) or impairment of continence (higher with traditional surgery). Since, at the moment, reliable data to identify a treatment as a gold standard in the management of anal fistulas are lacking, the correct approach to this condition must consider all the anatomic and clinicopathological aspects of the disease; this knowledge joined to an eclectic attitude of the surgeon, who should be familiar with different types of treatment, is the only guarantee for a satisfactory treatment. As a conclusion, it is worthwhile to remember that adequate initial treatment significantly reduces recurrence, which, when it occurs, is usually due to failure to recognise the tract and primary opening at the initial operation.