Chronic Cryptoglandular Anal Fistulas: Surgical Outcomes; A Retrospective Case Control Study In 148 Patients with No Risk Factors for Recurrence

Background: The success rate of surgery for anal fistulas in the literature is variable, ranging between 30-90% due to differences in etiology, risk factors for recurrences and variety of surgical and innovative techniques used in therapy of anal fistulas. Aim: We try to evaluate the surgical outcomes in patients without any known risk factor for recurrence. Materials and Methods: A retrospective study with 148 patients was performed. Fistulas were classified according to: Parks system, the modified Parks’s and the St James’s University Hospital system. MRI, TRUS and EUA were the most useful examinations. The age, duration of symptoms, location of the fistula according to the transvers anal line, the grade of complexity of AF were studied. Only patients with cryptoglandular anal infection were enrolled excluding patients with acute, subacute phase of inflammation and risk factors for recurrence. Operations performed in treatment of AF were registered. Various parameters studied underwent statistical analysis; Student t test and chi-square or Fisher exact test were used for comparisons between continuous and categorical data respectively Results: 148 patients (112 males,36 females, age range 21-74yrs, mean age 44±13, male to female ratio 3.1/1) were studied; 52(52/148, 35%) with simple and 96(96/148, 65%) with complex fistulas. MRI was necessary for classification of anal fistulas and identified the internal opening of fistula in134 patients (134/148, 93%) and in 14 inconclusive cases was identified by TRUS. LIFT was performed in complex fistulas and low intersphinceric fistulas in 102 patients (102/148, 68.6%). Fistulotomy in 41(41/148, 27.7%) with simple linear intersphincteric fistulas and laser therapy in 5(5/148, 3.4%) with simple low intersphincteric fistulas. A successful surgical outcome was achieved in 51 patients with simple (51/52, 98%) and 91(91/96, 94.8%) with complex fistulas.6 recurrences were detected (6/148, 4.05%). Conclusion: Chronic anal fistulas, in selected patients present postoperative healing rates at 98% and 94.8% for simple and complex fistulas respectively and recurrence rate at 4.05%. The most common operations were LIFT and fistulotomy.