Anal fistula and perianal abscess belong to two different stages of purulent infection of the perianal space. Their acute phase is perianal abscess, while the chronic phase, when the abscess breaks down, is anal fistula. Therefore, it can be said that anal fistula is an end of the development of perianal abscess. Perianal abscesses occur as a result of infection of the anal glands and the spread of inflammation to the perianal rectal interstitial tissue. The development and function of the anal glands are mainly regulated by human sex hormones, especially androgens. As androgens can cause the sebaceous and anal glands to secrete abundantly, if the anal ducts are blocked and the anal fluid is not excreted properly and stagnates, it can become infected and cause anal adenitis. This is the main cause of anal fistula. In the case of men, the androgens secreted in their bodies are often several times higher than in women, so the incidence of anal fistula is higher in men than in women, and the ratio is about 5-6:1.