Formation rate of secondary anal fistula after incision and drainage of perianal Sepsis and analysis of risk factors

BACKGROUND: The choice of surgery for perianal sepsis is currently controversial. Some people advocate one-time radical surgery for perianal sepsis, while others advocate incision and drainage. The objective of this study is to observe the formation probability of secondary anal fistula after incision and drainage in patients with perianal sepsis and determine factors that contribute to secondary anal fistula after incision and drainage. METHODS: A retrospective descriptive analysis was conducted in 288 patients with perianal sepsis who were treated with anorectal surgery in the Suzhou Hospital of Traditional Chinese Medicine from January 2016 to June 2018. The patients were followed by telephone, physical examination, and pelvic MRI examination for at least 1 year after surgery. RESULTS: Three patients were not followed, 98 patients did not receive surgical treatment or one-time radical surgery for perianal sepsis, and 187 patients were ultimately identified for the study. Anal fistula was present in 105 patients, and the rate of formation of secondary anal fistula was 56.15%. There was no statistically significant difference in the fistula formation rate between different types of sepsis (P>0.05). And, in patients with secondary anal fistula, there was no significant correlation between the location of sepsis and the type of secondary anal fistula (P>0.05). CONCLUSIONS: The incidence of secondary anal fistula after incision and drainage of perianal sepsis is 56.15%, which is lower than the incidence found in previous study. Young is a risk factor for secondary anal fistula after incision and drainage of perianal sepsis. There is no significant correlation between the location of sepsis and the type of secondary anal fistula. Simple incision and drainage is a suitable choice for patients with acute perianal sepsis.