Garg Classification for Anal Fistulas: Is It Better than Existing Classifications?—a Review

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.

Cutting seton versus decompression and drainage seton in the treatment of high complex anal fistula: a randomized controlled trial

This study aimed to compare the efficacy between decompression and drainage seton (DADS) and cutting seton (CS) in the treatment of high complex anal fistula. Patients were randomly assigned 1:1 to DADS or CS group. The primary outcome was the rate of wound healing. Second outcomes included time taken to return to work, postoperative pain, the severity of fecal incontinence and other complications. A total of 120 patients with a mean age of 39 years were included. There was no significant difference in the rate of complete wound healing at 1 year. The mean time taken to return to work was 5 ± 2 days in DADS group, shorter than CS group (10 ± 3, p < 0.001). Mean vaizey incontinence score and the post-operation pain in DADS group was significantly lower than CS group. No significant difference was found between two groups in the incidence of complications. DADS is as effective as Cutting seton for the treatment of high complex anal fistula but is associated with less postoperative pain and better sphincter function preserving.

Perianal fistulas: A review with emphasis on preoperative imaging

PURPOSE

We aim to present a comprehensive literature review which focuses on the preoperative imaging of perianal fistulas.

MATERIAL/METHODS

Pelvic magnetic resonance imaging (MRI) and endoanal ultrasound (EAUS) are the two first-line imaging modalities for the preoperative evaluation of patients with perianal fistulas. We conducted a search in PubMed, Scopus and Google Scholar concerning articles comparing pelvic MRI with EAUS, which were published from 1994 until 2019.

RESULTS

In most articles, pelvic MRI is superior to EAUS for the evaluation of perianal fistulas (especially for supralevator and extrasphincteric ones). Preoperative pelvic MRI is associated with statistically significant better results and prognosis after surgical treatment of the disease. Preoperative EAUS poses high sensitivity and specificity in identifying intersphincteric and transsphincteric perianal fistulas, as well as the internal opening of a fistula-in-ano. There is only one meta-analysis which compares the diagnostic accuracy of the two mentioned imaging modalities in preoperative fistula detection. Sensitivity of both - pelvic MRI and EAUS, is acceptably high (0.87). Specificity of pelvic MRI is 0.69 in comparison to EAUS (0.43), but both values are considered low.

CONCLUSIONS

Future well-designed prospective studies are needed to investigate the diagnostic accuracy of pelvic MRI and EAUS in the preoperative assessment of patients with perianal fistulas. Moreover, the combination of pelvic MRI and EAUS should also be studied, since several published articles suggest that it could lead to improved diagnostic accuracy. A novel treatment algorithm for perianal fistulas could arise from this study.

Management of Complex Cryptoglandular Anal Fistula: Challenges and Solutions

Anal fistulae can be a very difficult disease to manage. The management of complex fistulae is even more challenging. The risk to the fecal continence mechanism due to damage to the anal sphincters and refractoriness to the treatment (high recurrence rate) pose the two biggest challenges in the management of this disease. Apart from these, there are several other challenges in the treatment of complex fistulae. The intriguing and uphill task is that satisfactory solutions to most of these challenges are still not known, and there is hardly any consensus on whatever treatment solutions are available. To summarize, there is no gold-standard treatment available for treating complex anal fistulae, and the search for a satisfactory treatment option is still on. In this review, the endeavor has been to discuss and highlight recent path-breaking updates in the management of complex anal fistulae.

Assessing validity of existing fistula-in-ano classifications in a cohort of 848 operated and MRI-assessed anal fistula patients - Cohort study

Aim/background

The commonly used fistula-in-ano classifications, Park or St. James's University hospital(SJUH), neither grade fistulas as per their severity nor guide regarding their management. A new classification(NC), published in 2017, proposed to classify fistulas as per their severity and also guided in its management. The early grades (NC grade I & II) were simple fistulas and were amenable to fistulotomy whereas higher grades (NC grade III-V) were complex fistulas and were not amenable to fistulotomy.

Methods

Lower grades of all the three classifications were classified as simple (Parks: I, SJUH:I-II, NC:I-II) whereas higher grades were classified as complex (Parks: II-IV, SJUH: III-V, NC: III-V) fistulas. Fistulotomy should be possible in simple fistulas but not in complex fistulas. This was analysed for all these classifications. The long-term follow-up of continence was done by an objective scoring system (Vaizey's scores).

Results

The SJUH & Parks classifications categorized 504/828 fistulas as ‘complex’ which was quite inaccurate as 42.7%(215/504) of these fistulas were safely amenable to fistulotomy. On the other hand, the New classification (NC) classified 282/828 fistulas as ‘complex’ which was very accurate as 99% (279/282) of these were actually complex and were not amenable to fistulotomy. The change in the preoperative and the postoperative continence scores in the patients who underwent fistulotomy, as per these classifications, Parks & SJUH vs NC, was 0.064 ± 0.62 and 0.089 ± 0.85 respectively and was not significantly different(p = 0.80, Mann-Whitney U test).

Conclusions

The New classification(NC) seems better than the existing classifications for grading the disease as well as in guiding the management of the disease.

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Largest MRI-based series of operated anal fistula patients to be ever published.

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Analysis of 848 fistula patients to assess the validity of existing classifications.

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Objective continence scores (Vaizey's scores) of each patient was evaluated.

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New classification (2017) was far more accurate than Parks and SJUH classifications.

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It accurately graded the fistulas as per their severity and guided their management.

Perianal Tuberculosis: Lessons Learned in 57 Patients From 743 Samples of Histopathology and Polymerase Chain Reaction and a Systematic Review of Literature

BACKGROUND

Few data are published on perianal tuberculosis.

OBJECTIVE

This study aimed to determine the best method to diagnose tuberculosis in patients with fistula-in-ano and to conduct a systematic review to determine the incidence and characteristics of tuberculosis fistula-in-ano.

DATA SOURCES

The prospective study data and existing literature were derived from PubMed, Google scholar, and Scopus STUDY SELECTION:: Prospective analysis of patients with tuberculous fistula-in-ano treated between 2014 and 2018 was conducted, and a systematic review of studies describing ≥3 patients with tuberculosis fistula-in-ano was completed.

INTERVENTION

Testing of tuberculosis was performed by histopathology or polymerase chain reaction of tissue or pus from the fistula tract.

MAIN OUTCOME MEASURES

The primary outcomes measured were the detection rate of various tests to detect tuberculosis in fistula-in-ano and the prevalence rate of tuberculosis in simple versus complex fistulas.

RESULTS

In 637 samples (410 patients) tested, tuberculosis was detected in 49 samples (43 patients). Additional samples (n = 106) sent in patients with a high index of suspicion tested positive in 14 more patients. Thus, overall, 63 samples tested positive in 57 patients (total: 743 samples in 410 patients were tested). Tuberculosis was detected in 2 of 181 patients (1.1%) in tissue (histopathology), in 28 of 341 patients (8.2%) in tissue (polymerase chain reaction), and in 19 of 115 patients (16.5%) in pus (polymerase chain reaction) samples. To detect tuberculosis, tissue (polymerase chain reaction) was significantly better than tissue (histopathology) (28/341 vs 2/181, p < 0.00001) and pus (polymerase chain reaction) was significantly better than tissue (polymerase chain reaction) (19/115 vs 28/341, p < 0.0009). Tuberculosis was significantly more common in complex fistulas than in simple fistulas (20.3% vs 7.2%, p = 0.0002). The systematic review (n = 199) highlighted that tubercular fistulas are more common in recurrent and complex fistulas and in tuberculosis endemic regions.

LIMITATIONS

The true sensitivity and specificity of each testing modality could not be determined because not all patients with tuberculosis fistula-in-ano were tested by every diagnostic modality studied.

CONCLUSIONS

The tuberculosis detection rate of polymerase chain reaction was significantly higher than histopathology. Among polymerase chain reaction, pus had higher detection rate than tissue. Tuberculosis was associated with more complex and recurrent fistulas.

Anal fistula and pilonidal sinus disease coexisting simultaneously: An audit in a cohort of 1284 patients

Fistula-in-ano and pilonidal disease are not known to occur together. In a retrospective study, all patients having fistula-pilonidal disease coexisting simultaneously were included. Out of 1284 patients, 933 were operated (fistula-in-ano, 849; pilonidal disease, 77; and coexisting fistula-pilonidal, 7). A total of 351 patients did not undergo any surgery (two patients had coexisting fistula-pilonidal). Thus, a total of nine patients having coexisting fistula-pilonidal sinus were included in the study (mean age 35.8 ± 19.9 years, M/F 7/2). pIn 6/9 patients, the pilonidal tract was communicating with fistula-in-ano, and in 3/9 patients, they were not communicating/connected. The connection could be established preoperatively with the help of MRI. In all patients with communicating fistula-pilonidal sinus (n=6), the fistula was posterior. 6/9 patients had recurrent fistula and all (9/9) had multiple tracts. The fistula was high and complex in 8/9 patients (grade IV-7, grade V-1). 4/9 patients tested positive for tuberculosis while one patient was suffering from hidradenitis suppurativa. The latter improved on medical treatment. One patient did not agree for surgery and seven were operated. The disease healed in four patients, the disease did not heal in one patient, and two patients were in the convalescent stage. Anal fistula and pilonidal disease can coexist in a same patient and can even be connected. Such diseases are more complex and have a higher incidence of associated diseases like tuberculosis. Magnetic resonance imaging plays a pivotal role in diagnosis. If the connection is missed, the disease treatment becomes difficult.