Microbiological analysis and endoanal ultrasonography for diagnosis of anal fistula in acute anorectal sepsis

Hydrogen peroxide-enhanced magnetic resonance imaging: A novel approach for diagnosing anorectal-fistula

In this editorial, a commentary on the article by Chang et al has been provided, the course of treatment of anorectal fistulas, especially complex and recurring ones, require accurate diagnostic procedures for determining ideal surgical procedures. Conventional ways of imaging sometimes fall short, offering insufficient insights in aggravated instances. In this editorial, a novel application of hydrogen peroxide-enhanced magnetic resonance imaging (HP-MRI) that promises significant improvements in the imaging of anorectal fistula. Study is based on a retrospective investigation of 60 patients, contrasts the new HP-MRI with conventional diagnostic techniques such as physical examination, trans-perineal ultrasonography and poor spatial resolution MRI. The findings demonstrate HP-MRI's incredible diagnostic performance, with sensitivity and specificity rates of 96.08% and 90.91%, respectively, and unparalleled interobserver agreement (Kappa values ranging from 0.80 to 0.89). It has been a significant advancement for assessment of anorectal fistulas providing a better roadmap for surgical planning, lowering recurrence rates as well as reduced personal and financial burden on patients by reducing the need for repeated treatment and extended hospital stays. The remaining funds can be utilized for treatment of other medical need. Ultimately HP-MRI provides us a healthier & more efficient society by improvising patients well-being & optimized healthcare infrastructure.

Hydrogen peroxide-enhanced magnetic resonance imaging: A novel approach for diagnosing anorectal-fistula

In this editorial, a commentary on the article by Chang et al has been provided, the course of treatment of anorectal fistulas, especially complex and recurring ones, require accurate diagnostic procedures for determining ideal surgical procedures. Conventional ways of imaging sometimes fall short, offering insufficient insights in aggravated instances. In this editorial, a novel application of hydrogen peroxide-enhanced magnetic resonance imaging (HP-MRI) that promises significant improvements in the imaging of anorectal fistula. Study is based on a retrospective investigation of 60 patients, contrasts the new HP-MRI with conventional diagnostic techniques such as physical examination, trans-perineal ultrasonography and poor spatial resolution MRI. The findings demonstrate HP-MRI's incredible diagnostic performance, with sensitivity and specificity rates of 96.08% and 90.91%, respectively, and unparalleled interobserver agreement (Kappa values ranging from 0.80 to 0.89). It has been a significant advancement for assessment of anorectal fistulas providing a better roadmap for surgical planning, lowering recurrence rates as well as reduced personal and financial burden on patients by reducing the need for repeated treatment and extended hospital stays. The remaining funds can be utilized for treatment of other medical need. Ultimately HP-MRI provides us a healthier & more efficient society by improvising patients well-being & optimized healthcare infrastructure.

Antibiotic use during the first episode of acute perianal sepsis: a still-open question

PURPOSE

The role of antibiotics in preventing fistula formation following an initial abscess remains a subject of debate. This study compared the incidence of fistula in ano in patients experiencing their first episode of acute perianal sepsis, with and without antibiotic therapy, and evaluated the prevalence of fistula in ano necessitating surgical intervention at 1 year.

METHODS

This retrospective cohort study was conducted at a tertiary care hospital with a dedicated proctology department. All patients who presented to the emergency proctology unit with a first episode of acute perianal sepsis were eligible for inclusion.

RESULTS

This study included 276 patients. At 1 year, fistula formation was identified in 65.6% of all patients, 54.0% of those who had received antibiotics, and 75.0% of those who had not (P<0.001). This finding remained significant after weighted propensity analysis (odds ratio, 0.53; 95% confidence interval, 0.31-0.92; P=0.025).

CONCLUSIONS

The rate of fistula formation was relatively high in this study. However, it was lower among patients with perianal sepsis who were treated with antibiotics, although a causal relationship could not be established. Prolonged follow-up is needed to clarify the role of antibiotic therapy in preventing or delaying fistula development in patients with acute perianal sepsis.

Curing cryptoglandular anal fistulas-Is it possible without surgery?

BACKGROUND

Empirical reviews suggested that cryptoglandular anal fistulas require surgical resolution. However, some reports have indicated the possibility of nonsurgical and conservative treatment, which is discussed in this review.

METHODS

This review explores the potential of nonsurgical approaches for curing anal fistulas through bacterial inhibition and immunomodulation. The longstanding cryptoglandular theory has been a subject of controversy, prompting the reevaluation of conventional surgical interventions for anal fistulas. The review was conducted through database searches, including Medline, EMBASE, PubMed, and the Cochrane Library.

RESULTS

Emerging evidence suggests that targeting the anaerobic environments present in anal fistulas and perianal abscesses and eradicating bacteria and their by-products may be critical for successful treatment. Immunomodulatory strategies show promise as a potential avenue for the nonsurgical management of anal fistulas.

CONCLUSIONS

Ongoing developments in pharmacological research offer opportunities for alternative treatment options, shedding light on the prospects of noninvasive anal fistula management.

Proposal for a new classification of anorectal abscesses based on clinical characteristics and postoperative recurrence

BACKGROUND

Current surgical procedures for anorectal abscesses, including incision and drainage alone or combined concurrent fistulotomy, remain controversial primarily due to the unpredictability of postoperative recurrence or the progression to anal fistula.

AIM

To evaluate factors that predict postoperative recurrence of anorectal abscesses and propose a new classification to guide surgical procedures.

METHODS

In this retrospective study, 525 patients with anorectal abscesses treated by incision and drainage alone, at a tertiary general hospital from August 2012 to July 2022, were included. A new classification for anorectal abscesses based on their propensity to develop into fistulas, considering 18 other potential risk factors, was established. These factors, from electronic medical records, were screened for significance using the χ² test and subsequently analyzed with multivariate logistic regression to evaluate their relationship with postoperative recurrence of anorectal abscesses.

RESULTS

One year post-follow-up, the overall recurrence rate was 39%:81.0% and 23.5% for fistula-prone and non-fistula-prone abscesses, respectively. Univariate χ² analysis showed significant differences in recurrence rates based on anatomical classifications and pus culture results (P < 0.05). Fistula-prone abscess, ≥ 7 days between symptom onset and surgery, chronic diarrhea, preoperative antibiotic use, and local anesthesia were risk factors for recurrence, while diabetes mellitus was protective (P < 0.05). Moreover, fistula-prone abscess [odds ratio (OR) = 7.651, 95%CI: 4.049-14.458, P < 0.001], ≥ 7 days from symptom onset to surgery (OR = 2.137, 95%CI: 1.090-4.190, P = 0.027), chronic diarrhea (OR = 2.508, 95%CI: 1.216-5.173, P = 0.013), and local anesthesia (OR = 2.308, 95%CI: 1.313-4.059, P = 0.004) were independent risk factors for postoperative anorectal abscess recurrence using multivariate logistic regression. Body mass index ≥ 28 (OR = 2.935, 95%CI: 1.203-7.165, P = 0.018) was an independent risk factor for postoperative recurrence of non-fistula-prone abscess.

CONCLUSION

The choice of surgical procedure for treating anorectal abscesses should follow this new classification. Prompt and thorough incision and drainage can significantly reduce postoperative recurrence.

Aerobic Microbiological Spectrum and Antibiotic Resistance in Children Operated for Anorectal Abscesses

(1) Background: Anorectal abscesses are a relatively rare pathology in childhood. Most often, male children under 1 year of age are affected. The importance of microbiological examination for the diagnosis and treatment of such patients remains debatable among surgeons, resulting in scarce data being available in the literature. We aimed to identify the aerobic microbiological spectrum and antibiotic resistance of isolates in children undergoing operation to treat anorectal abscesses. (2) Methods: We performed a case series of 102 children diagnosed and operated for anorectal abscesses over a period of 10 years (2010-2019). Purulent wound exudate was used for microbiological evaluation, which was subsequently cultured on 5% sheep-blood agar and eosin-methylene blue agar. For microbiological identification, conventional biochemical tests and semi-automated (API 20, bioMerieux, Marcy-l'Étoile, France) tests were used, as well as automated systems (Vitek-2 Compact, bioMerieux, France). Antimicrobial susceptibility testing was performed by the disk diffusion method of Bauer-Kirby and by determining the minimal inhibitory concentrations for glycopeptides. The results were interpreted according to the EUCAST standard for the corresponding year. (3) Results: Microbiological testing in children operated for anorectal abscesses mainly identified the gut commensals that normally reside in the rectal mucosa. Monocultures were found in just over half of the cases. Escherichia coli, Klebsiella pneumoniae complex, and Proteus mirabilis were the most frequently isolated. In addition, Staphylococcus aureus was found in 7% of patients. In Gram-negative bacteria, antibiotic resistance was most often observed in penicillins, cephalosporins, sulfonamides, and fluoroquinolones. (4) Conclusions: The increasing rates of antimicrobial resistance impose the need for the local monitoring of circulating commensal bacteria associated with anorectal abscesses in children to guide antibiotic therapy when indicated.

Microbiomic signatures of anal fistula and putative sources of microbes

Anal fistula is a common perianal disease that typically develops from an abscess caused by in-flammation in the area. It has long been believed that intestinal microbes play a significant role in its development, considering its close relation to the intestinal environment. This work attempts to identify the microbiomic signatures of anal fistula, and putative sources of microbes by analyzing microbiomes of 7 anal fistula-associated sites in 12 patients. This study found that microbes in anal fistulas may originate from the skin surface in addition to the intestinal tract. This finding was further validated by NMDS analysis, which also indicated that the microbial communities in the inner and outer openings of the fistula were more similar to their surrounding environments. Using MaAslin2, the characteristics of the microbiome were examined, demonstrating a higher similarity between the abundant bacteria in the anal fistula samples and those found on the skin surface. Moreover, pin-to-pair analysis conducted on all subjects consistently showed a higher abundance of skin-sourced bacteria in anal fistulas. This study identifies the microbiomic signatures of anal fistula, and provides novel insights into the origin of microorganisms in anal fistulas.

The Role of Magnetic Resonance Imaging in Pre-operative Assessment of Anorectal Fistula With Surgical Correlation

Background Anorectal fistulas are chronic inflammations of peri-anal tissues that form a connection between the perineal skin and the anal canal. Accurate preoperative evaluation of the main fistula's trajectory and pelvic tissues is essential for effective surgical treatment of anal fistulas. The inability to detect concealed lesions may result in the recurrence of fistulas and the conversion of a simple fistula into a complex fistula. Magnetic resonance imaging (MRI) imaging can detect concealed pathways and abscesses, thereby exposing the intricate connection between the fistula and anal-sphincter complex. This data serves as a roadmap for making surgical decisions, thereby reducing the likelihood of illness recurrence and complications after surgery. Aim To evaluate the role of MRI in pre-operative assessment of an anorectal fistula, compare its findings with surgical results. Materials and methods The research was conducted at the Radiology Department, Apollo Hospital, Hyderabad. It was a prospective observational study. IBM SPSS Statistics for Windows, Version 17 (released 2008; IBM Corp., Armonk, New York, United States) was utilized for data analysis. The mean and standard deviation were computed. We further applied appropriate statistical tests to determine the significance of MRI features with pre-operative findings. Results MRI accurately detects features like abscesses (sensitivity-100%, specificity-97.06%), secondary tracts of the fistula (sensitivity-93.55%, specificity-94.12%), horseshoe appearance, and supralevator extension (sensitivity-100%, specificity-97.50%, and 97.62%, respectively). Conclusion When comparing our results with intraoperative findings, MRI showed high sensitivity and specificity in detecting abscesses, secondary tracts, horseshoe appearances, and supralevator extensions. Our findings suggest that MRI can offer anatomical and pathological information for the pre-operative care and surgical planning of perianal fistulas.

Where Are We and Where to Next?-The Future of Perianal Crohn's Disease Management

Perianal fistulizing Crohn's Disease (pCD) affects about 25% of patients with Crohn's Disease (CD). It remains a difficult entity to manage with a therapeutic ceiling of treatment success despite improving medical and surgical management. The refractory nature of the disease calls for an imminent need to better understand its immunopathogenesis and classification to better streamline our treatment options. In this article, we overview the current state of pCD management and discuss where the future of its management may lie.

Crohn's Disease-Associated and Cryptoglandular Fistulas: Differences and Similarities

Perianal fistulas are defined as pathological connections between the anorectal canal and the perianal skin. Most perianal fistulas are cryptoglandular fistulas, which are thought to originate from infected anal glands. The remainder of the fistulas mainly arises as complications of Crohn's disease (CD), trauma, or as a result of malignancies. Fistulas in CD are considered as a consequence of a chronic and transmural inflammatory process in the distal bowel and can, in some cases, even precede the diagnosis of CD. Although both cryptoglandular and CD-associated fistulas might look similar macroscopically, they differ considerably in their complexity, treatment options, and healing rate. Therefore, it is of crucial importance to differentiate between these two types of fistulas. In this review, the differences between CD-associated and cryptoglandular perianal fistulas in epidemiology, pathogenesis, and clinical management are discussed. Finally, a flow chart is provided for physicians to guide them when dealing with patients displaying their first episode of perianal fistulas.

The pathogenesis of cryptoglandular anal fistula: New insight into the immunological profile

AIM

The aetiology of cryptoglandular anal fistula (AF) is poorly understood. Evidence suggests that persistence and/or recurrence of the disease is more related to inflammatory than infectious factors. The aim of this study was to investigate the immune profile of cryptoglandular AF and to perform a histopathological characterization.

METHOD

Fistulectomy was performed in all patients; healthy ischioanal fat from the same patients was used as a control. Samples were evaluated by the Luminex xMAP system for the detection of 27 analytes. AF tissues were analysed using immunofluorescence. Staining was performed using primary antibodies to identify M1 inflammatory and M2 anti-inflammatory macrophages. Selective staining of total T lymphocytes and different T lymphocyte subsets was performed.

RESULTS

Twenty patients with AF underwent a fistulectomy. Specific cytokine pathways differentiated AF from healthy tissue: pro-inflammatory cytokines interleukin (IL)-1β, IL-4, IL-8 and IL-17 and the anti-inflammatory cytokine IL-10 were overexpressed in AF compared with controls. Chemokines involved in macrophage recruitment (CCL2, CCL3, CCL4) were higher in AF than in healthy fatty tissue. Moreover, we showed that Tc17 cells characterize AF patients, thus confirming the enzyme-linked immunosorbent assay data. Furthermore, elevated infiltration of CD68+ myeloid cells and a reduction of the M1/M2 ratio characterize AF patients.

CONCLUSION

A combination of inflammatory cytokines, chemokines and growth factors reside in the wound microenvironment of AF patients. For the first time an important prevalence of Tc17 cells and a reduction in the M1/M2 ratio was observed, thus suggesting new insights into the immunological characterization of AF patients.

Does Anti-TNF-α Therapy Affect the Bacteriological Profile of Specimens Collected from Perianal Lesions? A Retrospective Analysis in Patients with Crohn's Disease

Anal abscesses and fistulas are potential complications of Crohn’s disease (CD). Chronic immunosuppression, loose stools, and poor wound healing in this population present challenges to the management of perianal diseases. The purpose of the study was to determine the predominant bacterial species found in specimens from perianal lesions causing anal abscess and/or fistula drainage in hospitalized patients, and to compare the number and type of microorganisms isolated from samples taken from patients undergoing biological therapy or traditionally treated. The outcomes of studies of patients treated for anal abscesses or fistulas from 2017 to 2019 were evaluated. Data obtained from medical records included culture and antibiotic sensitivity results of swabs from perianal lesions of isolated microorganisms. A total of 373 swabs were collected from perianal lesions during the analysis period, including 51 (49 positive samples) from patients with CD. The predominant pathogen was Escherichia coli (55%, p < 0.001), the second most common microorganism was Staphylococcus aureus (14.3%, p < 0.001). In vitro susceptibility testing showed E. coli, ESBL (strain with Extended Spectrum Beta-Lactamase) in five cases, S. aureus, MRSA (methicillin-resistant S. aureus -resistant to all beta-lactam antibiotics: penicillins with inhibitors, cephalosporins, monobactams, carbapenems, except for ceftaroline) in one sample. Biologic therapy does not affect the type of microorganisms isolated from perianal abscesses in patients with CD.

Human Amniotic Membrane for the Treatment of Cryptoglandular Anal Fistulas

Background: Implantation of the amniotic membrane and their derivatives can have a beneficial effect on tissue repair and regeneration. We report for the first time the implant of an amniotic membrane in a patient affected by cryptoglandular anal fistula. Methods: A patch of human amniotic membrane was implanted in a female patient affected by an anterior transphincteric fistula. Following an accurate curettage of the anal fistula, the cryopreserved amniotic membrane was thawed and then washed in the operating room; one side of the membrane was transfixed with a resorbable suture thus creating an implantable fusiform patch. The membrane was subsequently implanted into the fistula tract from the external to the internal opening. The inner and outer parts of the membrane were then sutured to the internal and external fistula openings. Results: No intraoperative or postoperative complications occurred. The patient was discharged one day after the procedure after an uneventful hospitalization. At the 1-week, 1- and 3-month follow-up visits no pain (VAS 0) was referred by the patient and no inflammation was evident at the level of the previous external fistula opening. Conclusions: The implant of human amniotic membrane in a patient affected by cryptoglandular anal fistula was safely and easily performed. Moreover, future studies to assess the efficacy in the long-term follow-up are needed.

Significant presence of biofilm-producing gut-derived bacteria in anal fistula of chronic duration

Fistula-in-ano though not a life-threatening condition, yet its symptoms often significantly impact patients' social, intimate, and work lives. There is an established role of bacterial microflora in acute infections. However, we proposed that biofilm-forming organisms might be present in the microflora of anal fistula of prolonged duration. This aspect has rarely been studied earlier. Therefore, the study describes the microbiology of anal fistula and the biofilm-forming capacity of the isolated organisms. A total of 30 patients were included in the study as per the criteria. Anal fistula tissue sample, tissue fluid, and blood samples were collected from each individual. The collected specimens were detected for the presence of aerobic and anaerobic microflora through standard microbiological method and polymerase chain reaction. Furthermore, the role of biofilm formation by microtitre plate assay and serum matrix metalloproteinases-9 was also studied. The result showed significant predominance of gut-derived microflora with high-to-moderate biofilm-producing ability in anal fistulas of prolonged duration. The study emphasises the presence of biofilm-forming bacteria in chronic, non-healing fistula.

Current concepts in the pathogenesis of cryptoglandular perianal fistula

Cryptoglandular perianal fistula is a common benign anorectal disorder that is managed mainly with surgery. A fistula is typically defined as a pathological communication between two epithelialized surfaces. More specifically, perianal fistula manifests as an abnormal tract between the anorectal canal and the perianal skin. Perianal fistulas are often characterized by significantly decreased patient quality of life. The cryptoglandular theory of perianal fistulas suggests their development from the proctodeal glands, which originate from the intersphincteric plane and perforate the internal sphincter with their ducts. Involvement of proctodeal glands in the inflammatory process could play a primary role in the formation of cryptoglandular perianal fistula. The objective of this narrative review was to investigate the current knowledge of the pathogenesis of cryptoglandular perianal fistula with the specific aims of characterizing the potential role of proinflammatory factors responsible for the development of chronic inflammation. Further studies are crucial to improve the therapeutic management of cryptoglandular perianal fistulas.

Auditing the Routine Microbiological Examination of Pus Swabs From Uncomplicated Perianal Abscesses: Clinical Necessity or Old Habit?

Background

Obtaining pus swabs from perianal abscesses after incision and drainage for subsequent microbiological analysis is traditionally performed by general surgeons. Our aim is to assess the current practice in our institution, emphasizing on whether pus swabs were sent or not, as well as to identify any associations between the revealed microbiology and the occurrence of immediate post-operative complications and re-admission rates with fistula-in-ano up to 12 months post the emergency drainage. Finally, we aimed to identify if the any members of the surgical team reviewed at any stage post-operatively the results of the microbiological examination of the obtained pus swabs and if that resulted in changes of the patient management.

Methods

We reviewed the operative findings and perioperative antimicrobial management of all patients within our institution that required surgical treatment of perianal abscesses over a 6-week period and re-assessed them after 12 months from the performed drainage, with respect to re-admission and identification of occurred fistula-in-ano.

Results

A total of 24 patients met our inclusion criteria. Pus swabs were sent in 66.7% of cases and only a third of the requested microbiology reports were reviewed by a part of the surgical team. All patients were discharged prior to the release of the microbiology results with no subsequent change in the management plan. We did not find any consistent association between the microbiology results and re-admission with perianal abscess, with or without fistula-in-ano.

Conclusions

We do not recommend routine use of pus swabs when draining perianal abscesses unless clinical concerns arise, including recurrent perianal sepsis, immuno-compromised status or extensive soft tissue necrosis, especially when these features are associated with systemic sepsis.

Pathogenesis and persistence of cryptoglandular anal fistula: a systematic review

Anal fistulas continue to be a problem for patients and surgeons alike despite scientific advances. While patient and anatomical characteristics are important to surgeons who are evaluating patients with anal fistulas, their development and persistence likely involves a multifaceted interaction of histological, microbiological, and molecular factors. Histological studies have shown that anal fistulas are variably epithelialized and are surrounded by dense collagen tissue with pockets of inflammatory cells. Yet, it remains unknown if or how histological differences impact fistula healing. The presence of a perianal abscess that contains gut flora commonly leads to the development of anal fistula. This implies a microbiological component, but bacteria are infrequently found in chronic fistulas. Recent work has shown an increased expression of proinflammatory cytokines and epithelial to mesenchymal cell transition in both cryptoglandular and Crohn's perianal fistulas. This suggests that molecular mechanisms may also play a role in both fistula development and persistence. The aim of this study was to examine the histological, microbiological, molecular, and host factors that contribute to the development and persistence of anal fistulas.

Total fistulectomy, sphincteroplasty and closure of the residual cavity for trans-sphincteric perianal fistula in the elderly patient

BACKGROUND

Perianal fistula is a complex and frequent disease. At present, no treatment nor technique has shown an absolute superiority in terms of efficacy and recurrence rate. The technique has to be chosen considering the balance between faecal continence preservation and disease eradication. Rarely concomitant perianal abscess and fistula are treated at the same time, and often time to complete recovery is long.

AIMS

The aim of this study was to evaluate the possibility of treating the abscess and the fistula tract in one procedure with total fistulectomy, sphincteroplasty and an almost complete closure of the residual cavity, thus reducing the healing time in older patients.

METHODS

A non-randomized single-centre series of 86 patients from 2007 to 2012 with low-medium trans-sphincteric perianal fistula (< 30% of external sphincter involvement) with or without synchronous perianal abscess were treated with total fistulectomy, sphincteroplasty and closure of the residual cavity technique.

RESULTS

Success rate was 97.7% with a healing time of 4 weeks; overall morbidity was 16.2%; recurrence rate was 2.3%; no major alterations of continence were observed.

DISCUSSION

Fistulectomy, sphincteroplasty and closure of the residual cavity are associated with a low rate of recurrence and good faecal continence preservation in older patients. This technique can be safely used even with a concomitant perianal abscess, with reduction in healing time and in the number of surgical procedures needed.

CONCLUSIONS

Total fistulectomy with sphincteroplasty and partial closure of the residual cavity, as described, is a safe procedure but has to be performed by dedicated colorectal surgeons.

Immunopathological characterization of cryptoglandular anal fistula: a pilot study investigating its pathogenesis

AIM

The pathogenesis of cryptoglandular anal fistula (AF) is still under debate. Tissue inflammation could play a primary role. The pathological process of epithelial mesenchymal transition (EMT) might be involved but has never been investigated.

METHOD

In a prospective pilot study, 12 patients with an AF had a fistulectomy. The excised track was divided into proximal (intrasphincteric) and distal (extrasphincteric) parts which were subjected to standard histopathological examination. The cytokines IL-8 and IL-1beta were analysed as markers of inflammation, while EMT was evaluated by expression of TGF-beta, Vimentin, Zeb-1, Snail and E-cadherin. The mRNA and protein expression of these molecules was investigated by real-time PCR (RT-PCR), Western blot analysis and immunohistochemistry and was compared with that of the normal adjacent tissue.

RESULTS

Chronic inflammation and granulation tissue and a stratified epithelium were evident on standard histopathological examination. The cytokine IL-8 was more expressed in the proximal than the distal part of the track (fold increase 4.34 vs 3.60), while the reverse was found for IL-1beta (fold increase 1.33 vs 2.01); both were more intensely expressed compared with the normal anal mucosa. EMT was demonstrated, in both proximal and distal parts of the track, with an increase of TGF-beta, Vimentin, Zeb-1 and Snail and a mean decrease of E-cadherin. Western blot analysis and immunohistochemistry confirmed the protein expression.

CONCLUSION

The study suggests that chronic inflammation is present in cryptoglandular fistulas. The inflammatory pattern might be different in the proximal than in the distal part of the fistula track. The cytokines IL-1beta and IL-8 could play a possible role in fistula formation. The study demonstrates for the first time the potential importance of EMT in the pathogenesis of cryptoglandular AF.

Bacteriological study in perianal abscess is not useful and not cost-effective

BACKGROUND

The detection of gut organisms in perianal abscesses has been postulated to suggest an underlying communication with the anal canal. However, recent studies appear to contradict this observation. The aim of this study is to determine the value of bacteriological studies in perianal abscesses.

METHODS

A retrospective study of all patients who have had a surgical drainage of their perianal abscesses with concomitant microbiological examination from January 2010 to December 2012 was performed. Patients with known underlying anal fistula, Crohn's disease or previous perianal operations were excluded.

RESULTS

A total of 164 patients, median age of 42.0 years (range 8-87) comprising of 78.7% males formed the study group. Gut organisms were cultured in 143 (87.2%) samples while 12 (7.3%) demonstrated skin organisms and nine did not yield any bacterial growth (5.5%). Twenty-nine (17.7%) patients developed anal fistula and 34 (20.7%) patients had a recurrence of the perianal abscess. The median follow-up period was 1450 (14-2391) days. There was no significant association between the presence of gut organism and development of fistulas (odds ratio = 0.48; 95% confidence interval = 0.17-1.37) or recurrence of perianal abscess (odds ratio = 1.66; 95% confidence interval = 0.46-6.01).

CONCLUSION

Bacteriological culture in perianal abscess is not useful for predicting the development of anal fistula or abscess recurrence. Hence, there is no need to perform this investigation on a routine basis.

Impact of three-dimensional endoanal ultrasound on the outcome of anal fistula surgery: a prospective cohort study

AIM

The aim of the study was to evaluate the impact of three-dimensional endoanal ultrasound (3D-EAUS) on postoperative outcome in patients with anal fistula.

METHOD

This prospective study compared clinical and functional outcomes of patients with and without preoperative 3D-EAUS examination 1 year after anal fistula surgery. Patients were prospectively followed and evaluated by a standardized protocol including physical examination, the Wexner Incontinence Score (WIS) and anorectal manometry, at baseline and 1 year after surgery.

RESULTS

A total of 196 patients were enrolled. There were no significant differences in demographic and operative parameters, except for operation time, between the two groups. At 1 year follow-up, the overall recurrence rates were 8.8% (9/102) in the 3D-EAUS group and 13.8% (13/94) in the examination under anaesthesia (EUA) group. In the subgroup of patients with complex fistulae, the recurrence rate was numerically lower in the 3D-EAUS group (12.8% vs 22.5%; P = 0.26). The WIS in the EUA group significantly worsened (0.35 ± 0.94 vs 1.07 ± 1.59; P = 0.003) with a decreased the number of fully continent patients (82.5% vs 55%; P = 0.008) while neither the WIS nor the proportion of fully continent patients changed in the 3D-EAUS group. Fewer patients in the 3D-EAUS group developed incontinence postoperatively (6.7% vs 33.3%; P = 0.012) and they had better maximum resting pressure and maximum squeeze pressure than the EUA group.

CONCLUSIONS

Preoperative use of 3D-EAUS had a favourable impact on the outcome of surgical treatment for anal fistulae, especially in those with complex anal fistula. It should be routinely used in the clinical setting.

Assessment of microbiota and peptidoglycan in perianal fistulas

Transanal advancement flap repair has been advocated as the treatment of choice for high transsphincteric perianal fistulas, but fails in 1 of every 3 patients. Persistence of the fistula after flap repair might be the result of ongoing disease in the remaining fistula tract. In 10 specimens of the distal part of the fistula, microbiota was assessed by means of conventional microbiological culture and 16S rRNA gene sequencing. Proinflammatory bacterial peptidoglycan and recognition proteins were assessed by immunohistochemistry. Bacterial species were bowel derived, skin derived, or a combination of both. No mycobacterium species were identified. 16S rRNA gene sequencing failed to identify bacteria in all but 1 specimen, most likely as a result of low numbers of organisms. Peptidoglycan was detected in 90% of the patients, and a host response to peptidoglycan in 60%. Therefore, we suggest that peptidoglycan might play a role in the ongoing inflammation in perianal fistulas.

Candida albicans as the Sole Organism Cultured from a Perirectal Abscess

Perirectal abscess is a common colorectal condition that may be present with or without a fistula. In most cases where a fistula coexists the organisms cultured are gut-derived organisms whereas skin-derived organisms are more common in patients without fistula formation. Candida albicans, despite being an microorganism often found in the gastrointestinal tract, has not previously been reported as an isolate from a perirectal abscess culture. Here we report the case of a patient taking cefazolin in whom a perirectal abscess was diagnosed via computed tomography and aspiration of which demonstrated growth of only C. albicans. Prior literature has demonstrated that the microorganisms cultured from patients with perirectal abscesses do not differ between patients in whom antimicrobials had been used previously and those who were antimicrobial-naïve, suggesting that there is a possibility that C. albicans is the sole organism responsible for the perirectal abscess in our patient. The patient underwent surgical drainage and was discharged with fluconazole and piperacillin/tazobactam, which led to the satisfactory recovery of the patient.

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.

German S3 guideline: anal abscess

BACKGROUND

The incidence of anal abscess is relatively high, and the condition is most common in young men.

METHODS

A systematic review of the literature was undertaken.

RESULTS

This abscess usually originates in the proctodeal glands of the intersphincteric space. A distinction is made between subanodermal, intersphincteric, ischioanal, and supralevator abscesses. The patient history and clinical examination are diagnostically sufficient to establish the indication for surgery. Further examinations (endosonography, MRI) should be considered in recurrent abscesses or supralevator abscesses. The timing of the surgical intervention is primarily determined by the patient's symptoms, and acute abscess is generally an indication for emergency treatment. Anal abscesses are treated surgically. The type of access (transrectal or perianal) depends on the abscess location. The goal of surgery is thorough drainage of the focus of infection while preserving the sphincter muscles. The wound should be rinsed regularly (using tap water). The use of local antiseptics is associated with a risk of cytotoxicity. Antibiotic treatment is only necessary in exceptional cases. Intraoperative fistula exploration should be conducted with extreme care if at all; no requirement to detect fistula should be imposed. The risk of abscess recurrence or secondary fistula formation is low overall, but they can result from insufficient drainage. Primary fistulotomy should only be performed in case of superficial fistulas and by experienced surgeons. In case of unclear findings or high fistulas, repair should take place in a second procedure.

CONCLUSION

In this clinical S3 guideline, instructions for diagnosis and treatment of anal abscess are described for the first time in Germany.

Comparison of accuracy of physical examination and endoanal ultrasonography for preoperative assessment in patients with acute and chronic anal fistula

BACKGROUND

This study was undertaken to evaluate the accuracy of endoanal ultrasonography for preoperative assessment of anal fistula, with special reference to the difference between acute and chronic fistula.

METHODS

The subjects comprised 401 patients treated for acute or chronic anorectal sepsis of cryptoglandular origin during the period January through December 2005. All patients underwent physical examination and endoanal ultrasonography. Agreement between the physical and endosonographic findings and the definitive surgical findings were evaluated with special reference to classification of the primary tract and horseshoe extension and localization of the internal opening. The difference in accuracy of endosonographic assessment between acute and chronic fistula was also evaluated.

RESULTS

The accuracy of endoanal ultrasonography was significantly higher than that of physical examination in detecting the primary tract (88.8% vs. 85.0%, p=0.0287) and horseshoe extension (85.7% vs. 58.7%, p<0.0001) and in localizing the internal opening (85.5% vs. 69.1%, p<0.0001). Furthermore, localization of the internal opening by endosonography was significantly more accurate in chronic fistula than in acute fistula (89.5 % vs. 76.8%, p<0.0001), although the accuracy in detecting the primary tract and horseshoe extension was not significantly different.

CONCLUSIONS

Endoanal ultrasonography is reliable and useful for preoperative assessment of anal fistula, particularly for detecting horseshoe extension and localizing the internal opening. Endosonographic assessment provides clearer depiction of the internal opening during periods of quiescence than during the period of abscess formation. For patients with acute anorectal sepsis, initial surgical drainage and subsequent fistula surgery, rather than one-stage fistula surgery, may be advisable to avoid misidentification of the internal opening.

The patient with persistent perianal fistulae

The management of patients with persistent perianal fistulae depends on thorough evaluation by clinical history and examination, assessment of intestinal disease and assessment of perianal disease. The main therapeutic options are medical and surgical treatment and their appropriate integration is essential for the optimal management of the patients. Medical treatment includes antibiotics, azathioprine or 6-mercaptopurine, infliximab and tacrolimus or cyclosporine. Surgical treatment includes fistulotomy, placement of setons, endorectal advancement flaps, fecal diversion and proctectomy. Fistula recurrence often occurs, possibly due to early discontinuation of medication or premature removal of setons. Using anorectal endoscopic ultrasound or magnetic resonance imaging to guide therapy, the healing rates of perianal fistula can be increased. In persistent complex perianal fistulae where medical treatment initially fails, examination under anaesthesia and placement of non-cutting setons, when necessary, combined with medical treatment results in higher healing rates.