Immediate Treatment of Anal Fistula Presenting With Acute Abscess: Is It Time to Revisit?

Non-Locatable Internal Opening in Anal Fistula Associated with Acute Abscess and Its Definitive Management by Garg Protocol

Background

Definitive management of acute fistula-abscess (anal fistulas associated with acute abscess) is gaining popularity against the two-staged approach (early abscess drainage with deferred fistula management). However, locating an internal opening (IO) in acute fistula-abscess can be difficult. A recent protocol (Garg protocol) has been shown to be effective in managing anal fistulas with non-locatable IO.

Purpose

To test the efficacy of the Garg protocol in managing acute fistula-abscess with non-locatable IO.

Methods

Patients with acute fistula-abscess operated by a definitive procedure were included. A preoperative MRI was done in all patients. Patients in whom the IO was non-locatable after clinical, MRI, and intraoperative examination were managed by the three-step Garg protocol. Garg protocol: 1) Reassessment of MRI; 2) In non-horseshoe fistulas, the IO was assumed to be at the point where the fistula tract reached closest to the sphincter-complex; 3) In horseshoe fistulas, the IO was assumed to be located in the midline (anterior or posterior as per the horseshoe location). Low fistulas were treated by fistulotomy and high fistulas by a sphincter-sparing procedure. The long-term healing rate and change in continence (Vaizey scores) were evaluated.

Results

A total of 201 patients with acute fistula-abscess were operated over six years, and 19 were lost to follow-up. A total of 182 patients (154-males) were followed up (median-37 months). The IO was locatable in 133/182 (73.1%) (control group) and was non-locatable in 49/182 (26.9%) (study group). The study group was managed as per the Garg protocol. The age, sex-ratio, and fistula parameters were comparable in both groups. The long-term healing rate was 112/133(84.2%) in the IO-locatable group and 43/49 (87.8%) in the IO-non-locatable group (p=0.64, not-significant). The objective continence scores did not change significantly after surgery in both groups.

Conclusion

Acute fistula-abscess with non-locatable IO can be managed successfully by the Garg protocol without any risk of incontinence.

A Novel MRI and Clinical-Based Scoring System to Assess Post-Surgery Healing and to Predict Long-Term Healing in Cryptoglandular Anal Fistulas

Background

Anal fistulas cause great uncertainty and anxiety in patients and surgeons alike. This is largely because of the inability to accurately confirm postoperative fistula healing, especially long-term healing. There is no scoring system available that can objectively assess cryptoglandular anal fistulas for postoperative healing and can also accurately predict long-term healing.

Methods

Several parameters that could indicate anal fistula healing were assessed. Out of these, six parameters (four MRI-based and two clinical) were finalized, and a weighted score was given to each parameter. A novel scoring system (NSS) was developed. A minimum possible score (zero) indicated complete healing whereas the maximum weighted score (n = 20) indicated confirmed non-healing. Scoring was done with postoperative MRI (at least 3 months post-surgery), then compared with the actual healing status, and subsequently correlated with the final long-term clinical outcome.

Results

The NSS was validated in 183 operated cryptoglandular fistula-in-ano patients over a 3-year period in whom 283 MRIs (preoperative plus postoperative) were performed. The postoperative follow-up was 12–48 months (median-30 months). The NSS was found to have a very high positive predictive value (98.2%) and moderately high negative predictive value (83.7%) for long-term fistula healing. Additionally, its sensitivity and specificity in predicting healing were 93.9% and 94.7%, respectively.

Conclusion

Thus, this new scoring system is highly accurate and would be a useful tool for surgeons and radiologists managing anal fistulas. By objectivizing the assessment of postoperative healing, it can both ease and streamline management. Moreover, reliable prediction of recurrence-free long-term healing will greatly allay the apprehensions associated with this dreaded disease.