Abstract: Objective To explore the clinical value of simplified Fournier’s gangrene severity index(SFGSI) in accessing the prognosis of patients with perianal necrotizing fasciitis. Methods 52 patients with perianal necrotizing fasciitis who were diagnosed and underwent surgical treatment from January 1, 2010 to January 1, 2022.The patients were divided into survival group and death group according to the clinical outcome.We retrospectively analyzed the risk factors of death and the discrimination and calibration of SFGSI in accessing the prognosis of patients with perianal necrotizing fasciitis. Results A total of 52 patients were collected in this study,and they were grouped as survival group(group A,43 cases) and non-survival group(group B,9 cases).The total mortality was 17.31%.There were significant differences in age,potassium and SFGSI scores between survival group and death group(P<0.05):For every 5 year increase in age,the risk of death increased 2.033 times.The risk of death from abnormal potassium group was 3.656 times higher than normal group.When SFGSI > 2 ,the risk of death was 6.429 times higher than that of patients with SFGSI≤2.SFGSI has high accuracy in predicting the prognosis of patients，AUC =0.829(0.709-0.949). Conclusion SFGSI can be used to help predict the prognosis and death risk of perianal necrotizing fasciitis.

Key words: perianal necrotizing fasciitis, prognosis evaluation, simplified Fournier’s gangrene severity index, clinical value