Gore Bio-A® Fistula Plug: a new sphincter-sparing procedure for complex anal fistula

Improved fistula plug outcome depends on the type of plug: a single-centre retrospective study

AIM

Fistula-in-ano is a common condition that is potentially difficult to treat. In recent years 'sphincter-sparing' procedures have increased in popularity due to the lower rates of reported complications, such as incontinence. One such treatment is the fistula plug, which has seen varied success compared with other techniques. There are currently several plugs on the market and it is possible that difference in outcomes could be linked to the type of plug used. The aim of this study was to compare healing and complication rates between two fistula plugs in a single tertiary referral centre in the UK.

METHOD

We conducted a single-centre retrospective analysis of all patients over the age of 18 years who underwent elective fistula plug insertion, with two different fistula plugs over a 13-year period.

RESULTS

A total of 113 patients underwent fistula plug insertion (plug A n = 90; plug B n = 23). Plug B had been on the market for the final 4 years of the study period, hence the differing patient numbers. There was no difference in patient demographics, fistula type or aetiology of the fistula between the two plugs. Plug B had a significantly higher fistula healing rate compared with plug A (56.5% vs. 12.2%; p < 0.005). A quarter of all patients experienced a complication, 93% being those who had fistula plug A inserted. The most common complication was extrusion of the plug within 72 h of insertion.

CONCLUSION

This study demonstrated significantly different outcomes according to the type of fistula plug used. Whilst current randomized controlled trials have not found a significant difference in healing rates when comparing one type of fistula plug to other treatment modalities, this study suggests that plug type may influence efficacy.

Treatments for the amelioration of persistent factors in complex anal fistula

Anal fistulae are abnormal hollow connections between the wall of the anal canal and the perianal skin around the anus that have remained a burden on the medical sector for centuries. The complexity of this disease is attributed to a number of factors such as the degree of associated sphincter muscle, concomitant illnesses, existence of multiple fistulous tracts and the number of previous interventions. Persistence of a complex anal fistula can cause a decline in patient's physical quality of life as well as impact on the psychological status of patients who often suffer from anxiety and depression. Surgical intervention remains the gold standard for treatment, however; the risk of incontinence and high recurrence potential has led to interest into developing alternative treatment approaches such as the use of biologics, bioactives and biomaterials. One potential reason for these varied outcomes could be the multifactorial interplay between genetic, immune-related, environmental, and microbial persistence factors on tissue regeneration. Recent observations have proposed that adverse inflammatory mediators may contribute more than microbial factors. The moderate to high success rates of biotechnological advances (mesenchymal stem cells and biomaterial scaffolds) show promise as therapies for the amelioration of adverse persistent factors while facilitating a means to closing the fistula tract. The purpose of this review is to outline recent advances in biologics and combination therapies to treat persistent factors associated with complex anal fistula.

A Collective Review of Gore Bio-A Absorbable Synthetic Mesh in Cruroplasty Reinforcement

Background: Laparoscopic repair of hiatal hernia (HH) is associated with a considerable failure rate. Compared to suture repair alone, mesh-reinforced cruroplasty may be associated with fewer short-term recurrences, yet its use remains controversial. The aim of this study was to analyze the current literature assessing the use of Bio-A absorbable synthetic mesh in the reinforcement of primary crural closure after laparoscopic HH repair. Methods: A systematic review of primary literature in the MEDLINE and PubMed databases was conducted. We searched for investigations reporting patient outcomes in laparoscopic HH repair with onlay Gore Bio-A tissue reinforcement (W. L. Gore & Associates, Inc.) published between January 2008 and December 2019. The primary outcome was anatomical recurrence rate. Secondary outcomes were complication rate, symptomatic outcomes, and mortality. Results: Eight studies met inclusion criteria. There were two prospective and six retrospective cohort studies. In the included studies, laparoscopic HH repair was performed with Bio-A absorbable synthetic mesh in 734 patients. The anatomical recurrence data were extracted across all studies, and an objective recurrence was identified in 21/280 (7.5%) patients. There was only 1 (0.17%) mesh-related complication in the included studies. Conclusions: The use of Bio-A absorbable synthetic mesh in the repair of HHs may be promising, as it offers low rates of anatomical recurrence and mesh-related complications, but more data are still necessary to validate these findings. This collective review of literature is a basis for future randomized controlled trials to identify the most effective and safe mesh in the long term.

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.

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.

Video-Assisted Anal Fistula Treatment (VAAFT) for Complex Anal Fistula: A Preliminary Evaluation in China

BACKGROUND Although many attempts have been made to advance the treatment of complex anal fistula, it continues to be a difficult surgical problem. This study aimed to describe the novel technique of video-assisted anal fistula treatment (VAAFT) and our preliminary experiences using VAAFT with patients with complex anal fistula. MATERIAL AND METHODS From May 2015 to May 2016, 52 patients with complex anal fistula were treated with VAAFT at Yangpu Hospital of Tongji University School of Medicine, and the clinical data of these patients were reviewed. RESULTS VAAFT was performed successfully in all 52 patients. The median operation time was 55 minutes. Internal openings were identified in all cases. 50 cases were closed with sutures, and 2 were closed with staplers. Complications included perianal sepsis in 3 cases and bleeding in another 3 cases. Complete healing without recurrence was achieved in 44 patients (84.6%) after 9 months of follow-up. No fecal incontinence was observed. Furthermore, a significant improvement in Gastrointestinal Quality of Life Index (GIQLI) score was observed from preoperative baseline (mean, 85.5) to 3-month follow-up (mean, 105.4; p<0.001), and this increase was maintained at 9-months follow-up (mean, 109.6; p<0.001). CONCLUSIONS VAAFT is a safe and minimally invasive technique for treating complex anal fistula with preservation of anal sphincter function.

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.

Prospective evaluation of a new device for the treatment of anal fistulas

AIM: To evaluate the safety of the implantation of a new device for the treatment of anal fistulas. The short-term clinical efficacy was also assessed.

METHODS: This study took place at a tertiary care university hospital. Patients with a complex anal fistula of cryptoglandular origin were enrolled in the study and were treated with insertion of the new device. All patients were evaluated by clinical and physical examination, including an endoanal ultrasound at the baseline, and then at the 2 wk and 1, 2, 3 and 6-mo follow-up visits.

RESULTS: Morbidity, continence status, and success rate were the main outcome measures. Ten patients underwent the placement of the new device. The fistulas were transphincteric in eight patients and extrasphincteric in the remaining two. The median duration of the surgical procedure was 34.5 (range, 27-42) min. Neither intra- nor postoperative complications occurred, and all patients were discharged the day after the procedure. At the 6-mo follow-up evaluation, the final success rate was 70%. Three failures were registered: a device expulsion (on the 10^th postoperative day), the persistence of inflammatory tissue around the fistula tract (at the 2-mo follow up), and the persistence of serum discharge (at the 6-mo follow up). No patient experienced any change incontinence, as assessed by the Cleveland Clinic Fecal Incontinence score.

CONCLUSION: The technical procedure is simple and has low risk of perioperative morbidity. The pre- and post-operative continence status did not change in any of the patients. The initial results at the 6-mo follow up seem to be promising. However, a longer follow-up period and a larger sample size are needed to confirm these preliminary results.

Results of the Gore Bio-A fistula plug implantation in the treatment of anal fistula: a multicentre study

BACKGROUND

The aim of this prospective study was to determine the efficiency of the Gore Bio-A synthetic plug in the treatment of anal fistulas.

METHODS

A synthetic bioabsorbable anal fistula plug was implanted in 60 patients. All fistulas were transsphincteric and cryptoglandular in origin.

RESULTS

The healing rate after 1 year of follow-up was 52 % (31 out of 60 patients). No patient was lost to follow-up. The treatment had no effect on the incontinence score. The plug dislodgement rate was 10 % (6 out of 60 patients). Thirty-four per cent of the patients (16 out of 47) required reoperation. The average operating time was 32 ± 10.2 min, and the average length of hospital stay was 3.3 ± 1.8 days.

CONCLUSIONS

Synthetic plugs may be an alternative to bioprosthetic fistula plugs in the treatment of transsphincteric anal fistulas. This method might have better success rates than treatment with bioprosthetic fistula plugs.

Treating anal fistula with the anal fistula plug: case series report of 12 patients

Introduction

Recurrent and complex high fistulas remain a surgical challenge. This paper reports our experience with the anal fistula plug in patients with complex fistulas.

Methods

Data were collected prospectively and analyzed from consecutive patients undergoing insertion of a fistula plug from January 2011 through April 2014 at Hazrat-e-Rasoul Hospital in Tehran. We ensured that sepsis had been eradicated in all patients prior to placement of the plug. During surgery, a conical shaped collagen plug was pulled through the fistula tract.

Results

Twelve patients were included in this case study. All patients had previously undergone failed surgical therapy to cure their fistula and had previously-placed Setons. There were eight males and four females with an average age of 44 who were treated for complex fistulas. At a median time of follow-up of 22.7 months, 10 of the 12 patients had healed (83.3%). One patient developed an abscess that was noted on the sixth postoperative day, and there was one recurrence during follow-up.

Conclusions

Fistula plugs are effective for the long-term closure of complex anal fistulas. Success of treatment with the fistula plug depends on the eradication of sepsis prior to plug placement.

Delayed absorbable synthetic plug (GORE® BIO-A®) for the treatment of fistula-in-ano: a systematic review

AIM

Recent advances in the treatment of fistula-in-ano have focused on surgical techniques that preserve sphincter integrity. Plugs that obliterate the lumen of the fistula track have been proposed as one such method, and may be derived from biological or delayed absorbable synthetic materials. Biological plugs have highly variable results and have not been widely adopted. The aim of this systematic review was to assess the effectiveness and safety of a delayed absorbable synthetic plug (GORE® BIO-A®) for treatment of anal fistula.

METHOD

A systematic review of all literature in the English language relevant to the use of a plug to treat anal fistula and published between 1 January 2008 and 15 February 2015 was carried out by searching MEDLINE, EMBASE and the Cochrane Library of Systematic Reviews/Controlled Trials for relevant literature. Relevant articles were identified, quality assessed using the methodological index for nonrandomized studies criteria and data were extracted by two independent researchers (SKN and NNA). The identified articles were assessed with regard to fistula healing rate, duration of follow-up and complication rates related to the use of delayed absorbable synthetic fistula plugs.

RESULTS

Twenty six potential articles were identified from the literature search. Using the predefined inclusion and exclusion criteria, six were included in the final analysis, data extraction and data synthesis. Of these included in the review only three were prospective in design. Complete data were available for 187 of the 221 patients who underwent this treatment. The age of the participants ranged from 19 to 82 years. The fistula healing rates were reported to be between 15.8% and 72.7% at a follow-up ranging between 2 and 19 months. Early or delayed plug extrusion occurred in 16 (8.5%) of the 187 patients. Deterioration in continence was reported in 11 (5.8%) of 187 patients.

CONCLUSION

There are insufficient high-quality data on the delayed absorbable synthetic (GORE® BIO-A®) fistula plug to draw meaningful conclusions regarding its effectiveness. It does, however, appear to be a simple and safe technique associated with low complication rates and a minor deterioration in continence in a few cases.

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.

Revisiting an ancient treatment for transphincteric fistula-in-ano 'There is nothing new under the sun' Ecclesiastes 1v9

OBJECTIVE

The history of treatments for fistula-in-ano can be traced back to ancient times. Current treatment of transphincteric fistulae is controversial, with many options available. We reviewed the history of treatment using cutting setons and present our series of transphincteric fistulae in the light of the series in the literature.

DESIGN

Literature review and case series.

SETTING

Hospital based coloproctology service

PARTICIPANTS

140 consecutive patients presenting with fistula-in-ano were included.

MAIN OUTCOME MEASURES

The literature pertaining to treatment of transphincteric fistula was reviewed, along with the outcome of various treatment methods for this condition. Data were collected for 140 consecutive patients presenting with fistula- in-ano were assessed for fistula healing, recurrence and complications.

RESULTS

A total of 140 consecutive patients with fistula-in-ano were identified, of which 111 were cryptoglandular (79.3%). Eighty-one of these 111 were transphincteric (73.0%). At a median follow-up of 35 months (range, 2-83 months), 70 transphincteric fistulae had healed (86.4%), 10 were still undergoing treatment (12.3%) and one patient was lost to follow-up prior to treatment (1.2%). Two patients in this group required a stoma (2.5%), six patients developed recurrence (7.4%); three 'true' recurrences (3.7%). One (1.2%) developed a chronic fissure. There were no reported cases of incontinence.

CONCLUSIONS

The management of transphincteric fistula-in-ano is complex and controversial, for which no clear surgical procedure has gained acceptance as the gold standard. This study demonstrates that transphincteric fistulae can be successfully treated using cutting setons. A high healing rate (86.4%), low recurrence rate (7.4%) and a low complication rate (3.7%) are shown, which compares favourably with published rates over a long follow-up.

Prospective multicenter study of a synthetic bioabsorbable anal fistula plug to treat cryptoglandular transsphincteric anal fistulas

BACKGROUND

Although interest in sphincter-sparing treatments for anal fistulas is increasing, few large prospective studies of these approaches have been conducted.

OBJECTIVE

The study assessed outcomes after implantation of a synthetic bioabsorbable anal fistula plug.

DESIGN

A prospective, multicenter investigation was performed.

SETTING

The study was conducted at 11 colon and rectal centers.

PATIENTS

Ninety-three patients (71 men; mean age, 47 years) with complex cryptoglandular transsphincteric anal fistulas were enrolled. Exclusion criteria included Crohn's disease, an active infection, a multitract fistula, and an immunocompromised status.

INTERVENTION

Draining setons were used at the surgeon's discretion. Patients had follow-up evaluations at 1, 3, 6, and 12 months postoperatively.

MAIN OUTCOME MEASURES

The primary end point was healing of the fistula, defined as drainage cessation plus closure of the external opening, at 6 and 12 months. Secondary end points were fecal continence, duration of drainage from the fistula, pain, and adverse events during follow-up.

RESULTS

Thirteen patients were lost to follow-up and 21 were withdrawn, primarily to undergo an alternative treatment. The fistula healing rates at 6 and 12 months were 41% (95% CI, 30%-52%; total n = 74) and 49% (95% CI, 38%-61%; total n = 73). Half the patients in whom a previous treatment failed had healing. By 6 months, the mean Wexner score had improved significantly (p = 0.0003). By 12 months, 93% of patients had no or minimal pain. Adverse events included 11 infections/abscesses, 2 new fistulas, and 8 total and 5 partial plug extrusions. The fistula healed in 3 patients with a partial extrusion.

LIMITATIONS

The study was nonrandomized and had relatively high rates of loss to follow-up.

CONCLUSION

Implantation of a synthetic bioabsorbable fistula plug is a reasonably efficacious treatment for complex transsphincteric anal fistulas, especially given the simplicity and low morbidity of the procedure.

Modern management of anal fistula

Ideal surgical treatment for anal fistula should aim to eradicate sepsis and promote healing of the tract, whilst preserving the sphincters and the mechanism of continence. For the simple and most distal fistulae, conventional surgical options such as laying open of the fistula tract seem to be relatively safe and therefore, well accepted in clinical practise. However, for the more complex fistulae where a significant proportion of the anal sphincter is involved, great concern remains about damaging the sphincter and subsequent poor functional outcome, which is quite inevitable following conventional surgical treatment. For this reason, over the last two decades, many sphincter-preserving procedures for the treatment of anal fistula have been introduced with the common goal of minimising the injury to the anal sphincters and preserving optimal function. Among them, the ligation of intersphincteric fistula tract procedure appears to be safe and effective and may be routinely considered for complex anal fistula. Another technique, the anal fistula plug, derived from porcine small intestinal submucosa, is safe but modestly effective in long-term follow-up, with success rates varying from 24%-88%. The failure rate may be due to its extrusion from the fistula tract. To obviate that, a new designed plug (GORE BioA^®) was introduced, but long term data regarding its efficacy are scant. Fibrin glue showed poor and variable healing rate (14%-74%). FiLaC and video-assisted anal fistula treatment procedures, respectively using laser and electrode energy, are expensive and yet to be thoroughly assessed in clinical practise. Recently, a therapy using autologous adipose-derived stem cells has been described. Their properties of regenerating tissues and suppressing inflammatory response must be better investigated on anal fistulae, and studies remain in progress. The aim of this present article is to review the pertinent literature, describing the advantages and limitations of new sphincter-preserving techniques.

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.

Management of Fistula-in-Ano-The Current Evidence

Successful treatment for fistula in ano has eluded most surgeons. To choose the right surgery has been made more difficult, with new surgeries being added in the last decade. This article discusses the various accepted surgeries for fistula in ano - their pros & cons, & attempts to provide the status of the various procedures as it stands today.

A technical modification of video-assisted ablation for recurrent pilonidal sinus

AIM

The study evaluated, in a proof of concept, the usefulness of a prosthesis (plug) in addition to video assisted ablation of pilonidal sinus (VAAPS) for treatment of recurrent pilonidal sinus.

METHOD

This is a case series of recurrent complex pilonidal sinus treated by VAAPS plus plug positioning.

RESULTS

Four patients were analysed. All were successfully treated by this new approach. No difficulties in inserting the plug were identified. Complete healing was achieved in all cases. No infection or recurrence was reported during a limited follow-up.

CONCLUSION

This new technique allows a minimally invasive scarless approach to recurrent pilonidal sinus.

Histologic changes of implanted gore bio-a in an experimental animal model

Gore Bio-A has been reported to be an ideal synthetic bioabsorbable scaffold material for hernia repair. The purpose of this study was to determine the effectiveness of Gore Bio-A in soft tissue augmentation. Six New Zealand white rabbits were used in the study. Five subcutaneous pockets were created on the back of the rabbit, and 20 × 20 mm sized square shaped Gore Bio-A sheets, each 1.5 mm, 3 mm, 4.5 mm, 6 mm, and 7.5 mm in thickness, were implanted into each pocket (1 layer to 5 layers). To analyze the morphologic and histologic changes, the implants were harvested 1, 3, and 6 months after implantation. Following the gross analysis, absorption rate was accelerated with increased implant duration and decreased thickness. Histological analysis of the implants demonstrated progressive neovascularization, fibroblast infiltration, and neocollagenation over time. Six months after implantation, Gore Bio-A was almost absorbed and degenerated, not maintaining its volume. Based on this study, Gore Bio-A was revealed as a biocompatible material; however, it is not suitable for soft tissue augmentation because it is absorbed in the process of changing into soft tissue without maintaining its own volume. Therefore, this material is incomplete and needs more study to overcome this limitation.

Bioabsorbable synthetic plug in the treatment of anal fistulas

BACKGROUND

Management of anal fistulas is challenging, because surgeons must aim to obtain complete healing while sparing the sphincter and avoiding fecal incontinence. The optimal treatment method remains unknown.

OBJECTIVE

This study assessed the safety and effectiveness of the use of a new synthetic fistula plug made of bioabsorbable polymers in the treatment of cryptoglandular anal fistulas.

DESIGN

This study is a retrospective review of a database of patient records.

SETTING

: Patients were treated at a general hospital in Italy.

PATIENTS

Forty-eight patients (39 men and 9 women; mean age, 49.9 years) with 49 fistulas were treated with the synthetic plug between November 2009 and March 2012. Types of fistula were as follows: 24 superficial transsphincteric, 18 medium transsphincteric, 5 deep transsphincteric, and 1 medium intersphincteric.

INTERVENTIONS

The fistula tract was cleaned by using curettage, and a synthetic plug was sized to fit the tract and inserted. A draining seton was used preoperatively in 1 patient.

MAIN OUTCOME MEASURES

The outcome measures were complete closure of the fistula, with no discharge/residual fistula (verified by endoanal ultrasonography), perineal pain level (assessed with a visual analog scale), and fecal continence. Follow-up was conducted at 1 week and 1, 3, 6, and 12 months postoperatively.

RESULTS

The overall healing rate was 69.3% (34/49 fistulas, 33/48 patients). Eight patients (24.2%) had healing by 3 months after surgery, 21 patients (63.6%) had healed by 6 months, and 4 patients (12.1%) had healed by 12 months. By 3 months, no patient had perineal pain or fecal incontinence. No plug became dislodged, and no patient had the onset of anal stenosis, bleeding, local infection, or any other complication.

LIMITATIONS

The number of patients and the retrospective nonrandomized nature of the investigation are limitations of this study.

CONCLUSIONS

In patients with cryptoglandular anal fistulas, the use of a bioabsorbable synthetic plug provided a high rate of healing without causing fecal incontinence or other major adverse effects. Larger and randomized studies of this treatment are warranted.

The use of Gore Bio-A in the management of the open abdomen

Non-permanent, non-woven options for the closure of an open abdomen have previously been limited to biologics such as Permacol or Strattice. Gore Bio-A is constructed from biocompatible synthetic fibres, the use of which has only been described in the repair of inguinal hernia, hiatal hernia and fistula-in-ano. A 60-year-old male underwent emergency laparotomy, partial gastrectomy and formation of a feeding jejunostomy for a strangulated and perforated intrathoracic hiatus hernia. His abdominal wall subsequently dehisced for which he underwent laparostomy and subsequent early closure with a Gore Bio-A mesh, secured in an onlay manner with 2/0 vicryl. Functional and cosmetic outcomes were satisfactory and the patient was discharged home. The use of Gore Bio-A is a safe, feasible and cost effective alternative to traditional biologics for the closure of a laparostomy, deployment of which is safe within a contaminated field. Further prospective data is needed to clarify its role.

Fistulotomy with end-to-end primary sphincteroplasty for anal fistula: results from a prospective study

BACKGROUND

Fistulotomy plus primary sphincteroplasty for complex anal fistulas is regarded with scepticism, mainly because of the risk of postoperative incontinence.

OBJECTIVES

The aim of this study was to evaluate safety and effectiveness of this technique in medium-term follow up and to identify potential predictive factors of success and postoperative continence impairment.

DESIGN AND SETTING

This was a prospective observational study conducted at a tertiary care university hospital in Italy.

PATIENTS

A total of 72 patients with complex anal fistula of cryptoglandular origin underwent fistulotomy and end-to-end primary sphincteroplasty; patients were followed up at 1 week, 1 and 3 months, 1 year, and were invited to participate in a recent follow-up session.

MAIN OUTCOME MEASURES

Success regarding healing of the fistula was assessed with 3-dimensional endoanal ultrasound and clinical evaluation. Continence status was evaluated using the Cleveland Clinic fecal incontinence score and by patient report of post-defecation soiling.

RESULTS

Of the 72 patients, 12 (16.7%) had recurrent fistulas and 29 patients (40.3%) had undergone seton drainage before definitive surgery. At a mean follow-up of 29.4 (SD, 23.7; range, 6-91 months, the success rate of treatment was 95.8% (69 patients). Fistula recurrence was observed in 3 patients at a mean of 17.3 (SD, 10.3; range, 6-26) months of follow-up. Cleveland Clinic fecal incontinence score did not change significantly (p = 0.16). Eight patients (11.6% of those with no baseline incontinence) reported de novo postdefecation soiling. None of the investigated factors was a significant predictor of success. Patients with recurrent fistula after previous fistula surgery had a 5-fold increased probability of having impaired continence (relative risk = 5.00, 95% CI, 1.45-17.27, p = 0.02).

LIMITATIONS

The study was limited by potential single-institution bias, lack of anorectal manometry, and lack of quality of life assessment.

CONCLUSIONS

Fistulotomy with end-to-end primary sphincteroplasty can be considered to be an effective therapeutic option for the treatment of complex anal fistulas, with low morbidity, a high rate of success even at long-term follow-up, and a very low rate of postoperative major fecal incontinence, although minor impairment of continence (postdefecation soiling) may occur. Caution should be used in selecting patients with a history of recurrent fistula and fecal incontinence.

Repair of abdominal wall defects with biodegradable laminar prostheses: polymeric or biological?

Introduction

Biological and synthetic laminar absorbable prostheses are available for the repair of hernia defects in the abdominal wall. They share the important feature of being gradually degraded in the host, resulting in place the formation of a neotissue. This study was designed to assess the host tissue’s incorporation of collagen bioprostheses and a synthetic absorbable prosthesis.

Methods

Partial defects were created in the abdominal walls of 72 New Zealand rabbits and repaired using collagen bioprostheses Tutomesh® and Strattice® or a synthetic prosthesis Bio-A®. Specimens were collected for light microscopy, collagens gene and protein expression, macrophage response and biomechanical resistance at 14, 30, 90 and 180 days post-implantation.

Results

Tutomesh® and Bio-A® were gradually infiltrated by the host tissue and almost completely degraded by 180 days post-implantation. In contrast, Strattice® exhibited material encapsulation, no prosthetic degradation and low cell infiltration at earlier timepoints, whereas at later study time, collagen deposition could be observed within the mesh. In the short term, Bio-A® exhibited higher level of collagen 1 and 3 mRNA expression compared with the two other biological prostheses, which exhibited two peaks of higher expression at 14 and 90 days. The expression of collagen III was homogeneous throughout the study and collagen I deposition was more evident in Strattice®. Macrophage response decreased over time in biomeshes. However, in the synthetic mesh remained high and homogeneous until 90 days. The biomechanical analysis demonstrated the progressively increasing tensile strength of all biomaterials.

Conclusions

The tissue infiltration of laminar absorbable prostheses is affected by the structure and composition of the mesh. The synthetic prosthesis exhibited a distinct pattern of tissue incorporation and a greater macrophage response than did the biological prostheses. Of all of the laminar, absorbable biomaterials that were tested in this study, Strattice® demonstrated the optimal levels of integration and degradation.

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.

Gore BioA Fistula Plug in the treatment of high anal fistulas--initial results from a German multicenter-study

Background: Treatment of high anal fistulas may be associated with a high risk of continence disorders. Beside traditional procedure of flap-reconstruction the occlusion of the fistula tract using fistula-plugs offers a new sphincter-saving treatment option. In this study for the first time results from Germany are described.

Patients and method: 40 patients (30 male, 10 female, age 51±12 years) underwent closure of a high trans-sphincteric (n=28) or supra-sphincteric (n=12) fistula with Gore BioA Fistula Plug^® in three surgical departments. The surgical procedures had been performed by five colorectal surgeons. Four patients had Crohn’s disease. Preoperatively 33 patients were completely continent; seven patients complained of minor continence disorders. Treatment of the patients was performed on a intent-to-treat basis and evaluation of the results was retrospective using pooled data from each center.

Results: Postoperatively one patient developed an abscess, which had to be managed surgically. In two patients the plug had fallen out within the first two weeks postoperatively. Six months after surgery the fistula has been healed in 20 patients (50.0%). Three additional fistulas healed after 7, 9 rsp. 12 months. The overall healing-rate was 57.5% (23/40). The healing rate differs considerably between the surgeons from 0 to 75% and depends on the number of previous interventions. In patients having only drainage of the abscess success occurred in 63.6% (14/22) whereas in patients after one or more flap fistula reconstruction the healing rate decreased slightly to 50% (9/18). No patient complained about any impairment of his preoperative continence status.

Conclusion: By occlusion of high anal fistulas with a plug technique definitive healing could be achieved in nearly every second patients. Previous surgery seems to have a negative impact on success rate. We have not observed any negative impact on anal continence. From that point of view anal fistula plugs might be discussed as a treatment option for high anal fistulas, but further studies are needed to gain conclusive evidence.

Controversies in fistula in ano

Managing a complex fistula in ano can be a daunting task for most surgeons; largely due to the two major dreaded complications-recurrence & fecal incontinence. It is important to understand the anatomy of the anal sphincters & the aetiopathological process of the disease to provide better patient care. There are quite a few controversies associated with fistula in ano & its management, which compound the difficulty in treating fistula in ano. This article attempts to clear some of those major controversies.

A Bartter's-like syndrome from capreomycin, and a similar gentamicin tubulopathy

Marked renal potassium and magnesium wasting, alkalosis, and a progressive increase in plasma renin and eventual hyperaldosteronemia developed during a 15-month course of in-hospital capreomycin therapy that was necessary for drug-resistant pulmonary tuberculosis. A prominent feature of the present case was renal chloride wasting, a feature of the capreomycin syndrome that has previously received little attention. Similar potentially life-threatening metabolic abnormalities, which resemble those found in Bartter's syndrome, can occur during prolonged therapy with the antibiotic gentamicin. In the present case, electrolyte abnormalities were unaffected by three days of indomethacin therapy but were partially corrected by large doses of spironolactone. Capreomycin, viomycin (an antibiotic closely related to capreomycin), and gentamicin are highly basic polypeptide antibiotics that may induce strikingly similar and potentially fatal syndromes of renal tubular dysfunction that can feature multiple electrolyte abnormalities.