Type of lesion | Typical location | Common clinical presentations | Perianal inspection | Digital rectal examination |
Simple perianal fistula | Perianal skin | | | - Internal opening may be palpated
|
Complex perianal fistula | Perianal skin or buttocks | - Perianal drainage
- Perianal pain
| - One or more cutaneous opening(s)
| - Internal opening(s) may be palpated
|
Perianal abscess | Varies* | - Perianal pain, unrelated to bowel movements
- Fluctuation beneath perianal skin
- Cutaneous drainage of pus from fistula
- Fever may be present
| - Cutaneous area of erythematous induration and/or fluctuance
- Cutaneous opening if associated with fistula or spontaneous drainage
| - Diffuse tenderness may be present
- Palpable fluctuant mass or fullness
|
Anal fissure | Anal canal | - Rectal bleeding possible
- May be painless
| - Tear or laceration in the anoderm
- Bleeding may be visible
| - Tenderness of anal canal may be present
|
Anorectal stricture | Anal canal | - Fecal urgency and/or frequency
- Tenesmus
- Difficult evacuation
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