2006 ICD-9-CM Volume 1 Diagnosis Codes Home > Diseases Of The Digestive System 520-579 > Other Diseases Of Intestines And Peritoneum 560-569 > ICD-9-CM Diagnosis 565 Anal fissure and fistula 565 is a non-specific code that cannot be used to specify a diagnosis ICD-9-CM Diagnosis 565.0 Anal fissure A painful linear ulcer at the margin of the anus. It appears as a crack or slit in the mucous membrane of the anus and is very painful and difficult to heal. 565.0 is a specific code that can be used to specify a diagnosis 565.0 contains 5 index entries ICD-9-CM Diagnosis 565.1 Anal fistula An abnormal anatomical passage connecting the RECTUM to the outside, with an orifice at the site of drainage. 565.1 is a specific code that can be used to specify a diagnosis 565.1 contains 7 index entries