Signs and symptoms of an anal fissure
Idiopathic anal fissures are believed to result from trauma as a consequence of passing a large or hard stool. Whilst physical trauma may be the initiating event, a key characteristic is an increase in anal sphincter pressure (excessive tone). Coupled with a compromised local blood flow, this results in painful defecation and delayed healing.
- Pain, sometimes severe, during bowel movementsPain after bowel movements that can last up to several hours
- Bright red blood on the stool or toilet paper after a bowel movement
- Itching or irritation around the anus
- A visible crack in the skin around the anus
- A small lump or skin tag on the skin near the anal fissure
Causes and risk factors
Chronic constipation or frequent diarrhoea can also tear the skin around the anus.
- straining during childbirth or bowel movements
- inflammatory bowel disease (IBD), such as Crohn’s disease
- decreased blood flow to the anorectal area
- overly tight or spastic anal sphincter muscles
In rare cases, an anal fissure may develop due to: