[Quality indicators in the treatment of anal fistulas]

[Rectovaginal fistulas : Differentiated diagnostics and treatment]

Rectovaginal fistulas (RVF) represent less than 5% of anorectal fistulas. The classification of RVF is based on the localization (low vs. high) and the etiology. The most frequent causes of RVF are birth trauma, Crohn's disease, previous surgery and pelvic irradiation. In most cases a clinical diagnostic assessment is sufficient. Additionally, endosonography is a reliable tool to detect sphincter defects. Computed tomography (CT) and magnetic resonance imaging (MRI) are reserved for special situations (e.g., RVF related to anastomotic leakage, after pelvic irradiation or associated with complex perianal fistulizing Crohn's disease). The surgical treatment is primarily oriented to the localization and etiology. Surgical techniques range from local procedures (e.g., endorectal advancement flap repair, transvaginal or transperineal closure) up to more invasive tissue interposition (e.g., bulbocavernosus muscle fat tissue flap or transposition of the gracilis muscle). In "high" RVF transabdominal approaches such as coloanal anastomosis, pull through procedures or omental interposition are indicated. All surgical procedures show high recurrence rates. Several operations are mostly necessary and a stoma creation is often required.

Silk fibroin/chitosan-based anal fistula scaffolds loaded with curcumin and 5-aminosalicylic acid

The present work describes the development of silk fibroin (SF)/chitosan (CS)-based porous composite anal fistula scaffold (SCAFS) with anti-inflammatory and healing functions. The SCAFS comprises an inner layer made from degummed silk fiber using a vertical braiding machine, and an outer layer created by freeze-drying a mixture of short SF fibers and curcumin (CUR)/5-aminosalicylic acid (5-ASA) loaded SF/CS solution. Results revealed that the SCAFS has high porosity of 42.4 %, remarkable water absorption rate of 370.5 %, robust dry/wet compression resistance of 12.28 ± 2.61 N/3.08 ± 0.43 N. The in vitro & in vivo biocompatibility and anti-inflammatory effect of SCAFS were further examined. The expression of pro-inflammatory cytokine TNF-α, anti-inflammatory cytokine IL-10, CD31 and CD68 was determined by immunohistochemistry (IHC) staining, H&E staining, Immunofluorescence (IF) staining and Masson assay. The results showed that the scaffolds possess a sustainable drug release above 400 h, better biocompatibility and anti-inflammatory effect than the control groups (p < 0.05). Thus, the SCAFS has potential application in the treatment of Crohn's disease.

Efficacy of radial incision combined with tunnel floating line drainage in the treatment of high posterior horseshoe anal fistula and perianal flora: Randomized control trial

BACKGROUND

Due to the high prevalence of posterior horseshoe anal fistula and causing numerous complications, this study aimed to investigate the clinical effect of radial incision combined with tunnel floating line drainage (RCTD) and arc incision internal drainage in the treatment of the disease and the influence on perianal flora.

METHODS

Ninety-six subjects treated with high posterior horseshoe anal fistula were stochastically assigned to a joint group (RCTD), and control group (arc incision internal drainage). The operation-related conditions, complication rate, anal function, and recurrence rate of 6 months after operation were compared, and perianal secretions were collected before operation and 1 day after operation to detect the changes of microbial flora.

RESULTS

After operation, it was corroborated notable difference between joint group and control group in operation time, intraoperative blood loss, wound healing time, visual analogue scale score 6 hours after operation and phase I cure rate. Chi square test analysis showed notable difference between control group (27.08%) and joint group (10.40%) in incidence of complications, in terms of number of pathogens detected around anus, significantly smaller of the incremental change for the joint subgroup versus the control subgroup 1 day after operation.

CONCLUSION

RCTD can be the best choice for patients with high posterior horseshoe anal fistula. This operation method has the advantages of short operation time, less trauma, fewer complications, fast recovery of anal function, and can also reduce perianal pathogenic bacteria infection.

OTSC Proctology clip as appropriate treatment for complicated anorectal fistula

PURPOSE

Evaluation of the effectiveness and tolerability of the application of an OTSC (Ovesco Endoscopy AG Tuebingen, Germany) Proctology clip as an innovative strategy of anorectal fistulae closure when established treatment strategies had already failed or were not feasible.

METHODS

Retrospective single-center study including consecutive patients treated between March 2014 and March 2016 with the OTSC Proctology system for anorectal fistula closure, including one rectovaginal and one rectourethral fistula. The primary outcome was the healing rate with a minimum follow up of 6 months. Healing was defined as closure of the internal fistula ostium and absence of secretion or local inflammation during follow up.

RESULTS

A total of 66 fistula closures by the OTSC Proctology clip were investigated, including cryptoglandular fistulas (45/66 patients, 68%), fistulas associated with CED (19/66 patients, 29%), and other non-cryptoglandular fistulas (2/66 patients, 4%). 47% (31/66 patients) had a failed previous therapy. In that selected collective, a successful fistula closure was achieved in 29/66 cases (44%) after a median follow up time of 40 months (6-61 months). Suprasphincteric and high transsphincteric fistulas showed healing in 63% and 42% in CD associated fistulas.

CONCLUSION

Fistula closure by the OTSC Proctology clip is an innovative, sphincter protecting treatment strategy in anorectal fistulas that can achieve long-term cure in complex anorecta.

[Stem Cell Therapy for Complex Anal Fistula in Crohn`s Disease: Current Evidence and Future Perspectives]

Despite progress in multidisciplinary diagnostic and therapeutic strategies, complex anal fistulas associated with Crohn's disease remain a challenge for both medical and surgical management. Conventional surgical techniques such as flap procedures or LIFT are still associated with considerable persistence and recurrence rates. Based on this background, results of stem cell therapy for Crohn's anal fistula have shown promising results and are a sphincter-preserving technique. In particular, adipose-derived, allogeneic stem cell therapy (Darvadstrocel) has shown encouraging healing rates within the randomised controlled ADMIRE-CD trial, which were reproducible in "real world" data of limited clinical studies. The current evidence has led to the integration of allogeneic stem cell therapy into international guidelines. To date, the definitive status of allogeneic stem cells in the multidisciplinary treatment algorithm for complex anal fistulas associated with Crohn's disease cannot be evaluated.

Surgery of Simple and Complex Anal Fistulae in Adults: A Review of the Literature for Optimal Surgical Outcomes

Anal fistulas are common anorectal conditions, and surgery is the primary treatment option. In the last 20 years of literature, there exist a large number of surgical procedures, especially for the treatment of complex anal fistulas, as they present more recurrences and continence problems than simple anal fistulas. To date, there are no guidelines for choosing the best technique. We conducted a recent literature review, mainly the last 20 years, based on the PubMed and Google Scholar medical databases, with the goal of identifying the surgical procedures with the highest success rates, lowest recurrence rates, and best safety profiles. Clinical trials, retrospective studies, review articles, comparative studies, recent systematic reviews, and meta-analyses for various surgical techniques, as well as the latest guidelines of the American Society of Colon and Rectal Surgeons, the Association of Coloproctology of Great Britain and Ireland, and the German S3 guidelines on simple and complex fistulas were reviewed. According to the literature, there is no recommendation for the optimal surgical technique. The etiology, complexity, and many other factors affect the outcome. In simple intersphincteric anal fistulas, fistulotomy is the procedure of choice. In simple low transsphincteric fistulas, the patient's selection is crucial in order to perform a safe fistulotomy or another sphincter-saving technique. The healing rate in simple anal fistulas is higher than 95% with low recurrence and without significant postoperative complications. In complex anal fistulas, only sphincter-saving techniques should be used; the optimal outcomes are obtained by the ligation of the intersphincteric fistulous tract (LIFT) and rectal advancement flaps. Those techniques assure high healing rates of 60-90%. The novel technique of the transanal opening of the intersphincteric space (TROPIS) is under evaluation. The novel sphincter-saving techniques of fistula laser closure (FiLac) and video-assisted anal fistula treatment (VAAFT) are safe, with reported healing rates ranging from 65% to 90%. Surgeons should be familiar with all sphincter-saving techniques in order to face the variability of the fistulas-in-ano. Currently, there is no universally superior technique that can treat all fistulas.

Stem cell injection for complex anal fistula in Crohn’s disease: A single-center experience

BACKGROUND

Despite tremendous progress in medical therapy and optimization of surgical strategies, considerable failure rates after surgery for complex anal fistula in Crohn’s disease have been reported. Therefore, stem cell therapy for the treatment of complex perianal fistula can be an innovative option with potential long-term healing.

AIM

To evaluate the results of local administration of allogenic, adipose-derived mesenchymal stem cells (darvadstrocel) for complex anal Crohn’s fistula.

METHODS

All patients with complex anal fistulas associated with Crohn’s disease who were amenable for definite fistula closure within a defined observation period were potential candidates for stem cell injection (darvadstrocel) if at least one conventional or surgical attempt to close the fistula had failed. Darvadstrocel was only indicated in patients without active Crohn’s disease and without presence of anorectal abscess. Local injection of darvadstrocel was performed as a standardized procedure under general anesthesia including single-shot antibiotic prophylaxis, removal of seton drainage, fistula curettage, closure of the internal openings and local stem cell injection. Data collection focusing on healing rates, occurrence of abscess and follow-up was performed on a regular basis of quality control and patient care. Data were retrospectively analyzed.

RESULTS

Between July 2018 and January 2021, 12 patients (6 females, 6 males) with a mean age of 42.5 (range: 26-61) years underwent stem cell therapy. All patients had a minimum of one complex fistula, including patients with two complex fistulas in 58.3% (7/12). Two of the 12 patients had horse-shoe fistula and 3 had one complex fistula. According to Parks classification, the majority of fistulas were transsphincteric (76%) or suprasphincteric (14%). All patients underwent removal of seton, fistula curettage, transanal closure of internal opening by suture (11/12) or mucosal flap (1/12) and stem cell injection. At a mean follow-up of 14.3 (range: 3-30) mo, a healing rate was documented in 66.7% (8/12); mean duration to achieve healing was 12 (range: 6-30) wk. Within follow-up, 4 patients required reoperation due to perianal abscess (33.3%). Focusing on patients with a minimum follow-up of 12 mo (6/12) or 24 mo (4/12), long-term healing rates were 66.7% (4/6) and 50.0% (2/4), respectively.

CONCLUSION

Data of this single-center experience are promising but limited due to the small number of patients and the retrospective analysis.

Effect of intersphincteric fistula tract ligation versus anal fistulectomy on pain scores and serum levels of vascular endothelial growth factor and interleukin-2 in patients with simple anal fistulas

OBJECTIVE

This study was performed to explore the effects of ligation of the intersphincteric fistula tract (LIFT) on pain scores and serum levels of vascular endothelial growth factor (VEGF) and interleukin (IL)-2 in patients with simple anal fistulas.

METHODS

Ninety patients with simple anal fistulas were evenly randomized into a study group (treated with LIFT) and a control group (treated with traditional anal fistulectomy) according to a random number table. The surgical outcomes, basic operation conditions (operation time, hospital stay, and anal continence), and postoperative wound healing rates were compared between the two groups.

RESULTS

The study group had significantly better operation conditions (better anal continence and shorter length of hospital stay), a higher postoperative wound healing rate, lower pain scores, higher VEGF and IL-2 levels, and higher overall efficacy rate than the control group. However, the incidence of postoperative complications was not significantly different between the two groups.

CONCLUSIONS

Patients who underwent LIFT had better surgical outcomes, higher wound healing rates, better anal continence, a shorter length of hospital stay, and less severe postoperative pain than those who underwent simple anal fistulectomy. Increased levels of VEGF and IL-2 after surgery may promote wound healing.

Efficacy of flap repair for anal fistula: study protocol for a systematic review of randomized controlled trial

BACKGROUND

Clinical trials have reported that flap repair (FR) can treat anal fistula (AF) effectively. However, no study systematically investigated its efficacy and safety for patients with AF. This study will systematically assess its efficacy and safety of AF.

METHODS

We will retrieve MEDLINE, EMBASE, Cochrane Library, Elsevier, Springer, Web of Science, Scopus, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, VIP Information, and Wanfang Data from their inceptions to May 1, 2019 without any language limitations. The primary outcome is fistula cure rate. The secondary outcomes consist of fistula recurrence rate, fecal continence, quality of life, and complications. RevMan 5.3 software will be used for methodological quality assessment, data synthesis, subgroup analysis and sensitivity analysis.

RESULTS

The results of this study will summarize a high-quality synthesis of current evidence for the treatment of FR for patients with AF.

CONCLUSION

The findings of this proposed study will provide evidence for judging whether FR is an effective and safety intervention for AF or not.PROSPERO registration number: PROSPERO CRD42019135507.