Risk of Recurrent Fistula or Abscess After LIFT Surgery
In a healthy adult with a healed low-grade cryptoglandular anal fistula after LIFT, the risk of recurrence ranges from 18-27%, with most failures occurring within 4-8 months, though late failures can occur years later. 1, 2, 3, 4
Recurrence Rates: What the Evidence Shows
The published data on LIFT recurrence reveals important nuances:
- Initial optimistic reports suggested recurrence rates as low as 1.6%, but these likely represent underreporting due to heterogeneous follow-up periods and varying definitions of success 1
- More realistic contemporary data shows recurrence rates of 18-27% with adequate follow-up, with one prospective series documenting 21% recurrence 1, 2, 3, 4
- Primary healing rates range from 73-82% in cryptoglandular fistulas, meaning 18-27% experience treatment failure 5, 3, 4
- Median time to failure is approximately 4 months when recurrence occurs, though progressive failure over time is well-documented 1, 2
Critical Risk Factors That Increase Recurrence
Patient-Specific Factors
- Smoking at time of surgery increases failure risk dramatically (hazard ratio 3.2), and this risk persists throughout follow-up 1, 2, 6
- Active proctitis doubles the failure risk (hazard ratio 2.0) and can cause late breakdown of initially healed tracts 1, 2, 6
- Complex fistulas (branching, multiple tracts) show only 50-53% success rates compared to 80% in simple fistulas 1, 2
Factors That Do NOT Significantly Affect Outcomes
- Prior seton drainage does not increase recurrence risk 1
- Previous repair attempts do not significantly worsen outcomes 1
- Biologic therapy use does not negatively impact LIFT success 1
Understanding the Pattern of Failure
Progressive failure over time is a critical concept that patients must understand:
- Failures occur both early (within 3-8 months) and late (years after initial healing) 2, 3, 4
- The British Society of Gastroenterology acknowledges progressive failure over time, not just immediate failures 2
- Late recurrences relate to both treatment failure and recurrent disease, particularly in patients with complex anatomy or ongoing inflammatory processes 2
What Happens If LIFT Fails
The reassuring news about LIFT failure:
- LIFT failure does not worsen incontinence, and 53% of patients actually experience improvement in fecal continence postoperatively 6
- Incontinence rates after LIFT are dramatically lower at 1.6% versus 7.8% with advancement flaps 1, 6, 7
- In the four patients without primary healing in one series, the transsphincteric fistula was converted into an intersphincteric fistula, allowing subsequent fistulotomy with preservation of the external anal sphincter 5
Monitoring Strategy to Detect Recurrence
Follow specific intervals to catch recurrence early:
- Week 1-2: Assess for signs of infection 1
- Week 4: Evaluate external opening healing 1
- Week 8: Confirm healing progress 1
- Month 4-6: Identify early recurrence (when most failures occur) 1, 3, 4
- Beyond 6 months: Continue surveillance for late failures 1, 2
Consider MRI if clinical uncertainty exists about tract obliteration, particularly in patients with complex fistulas, as MRI evidence of fibrotic tract predicts no reinterventions during long-term follow-up 1
Critical Pitfall to Avoid
Aggressive probing during examination of a failed LIFT can convert a manageable recurrence into a complex fistula, so gentle examination is essential 2, 6
Comparison to Natural History of Untreated Disease
For context, in cryptoglandular disease after abscess drainage alone (without LIFT), one-third of patients develop a perianal fistula, with patients under 40 years and non-diabetic patients at higher risk 8