Recurrence Pattern of Fistula-in-Ano in a Chinese Population

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Poon Chi-Ming, Ng Dennis Chung-Kei, Cheung Michael Ho-Yin, Li Raymond Shiu-Ki, Leong Heng-Tat

Department of Surgery, North District Hospital, Hong Kong SAR, China


Background and aims: Fistula-in-ano is a common colorectal complaint. Despite of the advancement in preoperative imaging and surgical techniques, recurrence is not uncommon in this disease entity. We aimed to determine the recurrence pattern and predictors of FIA in Chinese population.

Methods: Setting: single regional hospital serving a 300,000 population. Design and Participants: A systematic retrospective review of inpatient and follow up records and operation records in patients with diagnosis of fistula-in-ano (ICD code - 565.1) from January 2001 to December 2004 was performed. Intervention: Surgery for fistula-in-ano.

Results: 135 out of 137 Chinese patients received anal fistula operations. 14 patients (10.4%) had high type anal fistulas and 27 patients (20%) had perianal sinus. The most common operation was combined fistulotomy-fistulectomy (78 patients, 57.8%). 18 patients (13.3%) had recurrence with a median time to recurrence of 7.5 months. Six factors including: 1) positive history of perianal abscess, 2) previous perianal operation, 3) complex fistula, 4) perianal sinus, 5) absence of an internal opening, 6) surgical procedure of sinus tract excision were significantly associated with recurrence in univariate analysis. Sinus tract excision was the only independent factor to predict recurrence in logistic regression (p=0.002, 95%CI=1.29-3.27).

Conclusion: Fistula-in-ano carried a significant risk of recurrence in perianal sinus with sinus tract excision performed. No difference was found between Chinese and Caucasian in recurrence pattern of fistula-in-ano.

Key words
Fistula-in-ano - recurrence - endoanal ultrasound