Anal fissure

Background

• Superficial linear tear of anal canal from at/below dentate line to anal verge
  • May be due to passage of hard stool, frequent diarrhea, or abuse
• Most common cause of painful rectal bleeding
• In >90% of cases anal fissures occur in the midline posteriorly
  • Nonhealing fissure or one not located in midline suggests alternative dx

Clinical Findings

• Acute sharp, cutting pain most severe during and immediately after bowel movement
  • Subsides between bowel movements (distinguishes fissure from other anorectal disease)
• Bright red bleeding, small in quantity (usually noticed only on toilet paper)
• Lateral to anus often indicates associated systemic illness such as Crohns, HIV, Leukemia, TB, syphillis

Diagnosis

• Having patient bear down may make fissure more noticable
• Sentinel pile, located at distal end of fissure, along with deep ulcer suggests chronicity
  • Often misdiagnosed as an external hemorrhoid

Differential Diagnosis

Anorectal Disorders

• Anal fissure
• Anal fistula
• Anal malignancy
• Anal tags
• Anorectal abscess
• Colorectal malignancy
• Condyloma acuminata
• Constipation
• Crohn's disease
• Cryptitis
• GC/Chlamydia
• Hemorrhoids
  • Internal hemorrhoid
  • External hemorrhoid
• Pedunculated polyp
• Pilonidal cyst
• Proctitis
• Pruritus ani
• Rectal foreign body
• Rectal prolapse
• Syphilitic fissure

Undifferentiated lower gastrointestinal bleeding

• Upper GI Bleeding
• Diverticular disease
  • Diverticulosis
  • Diverticulitis
• Vascular ectasia / angiodysplasia
• Inflammatory bowel disease
• Infectious colitis
• Mesenteric Ischemia / ischemic colitis
• Meckel's diverticulum
• Colorectal cancer / polyps
• Hemorrhoids
  • Internal hemorrhoid
  • External hemorrhoid
• Aortoenteric fistula
  • Nearly 100% mortality if untreated
  • Consider in patients with gastrointestinal bleeding and known abdominal aortic aneurysms or aortic grafts
• Rectal foreign body
• Rectal ulcer (HIV, Syphilis, STI)
• Anal fissure

Management

1. Hot sitz baths 15 min TID-QID and after each bowel movement
   1. Provides symptomatic relief and relieves anal sphincter spasm
2. Topicals
   1. Pain control with lidocaine
   2. Vasodilators such as nitroglycerin ointment
   3. Hydrocortizone
3. High-fiber diet
   1. Prevents stricture formation by providing a bulky stool
4. Meticulous anal hygiene is imperative; after defecation anus must be cleaned thoroughly
5. Surgical referral indicated if healing does not occur in a reasonable amount of time

Complications

1. Perianal abscess
2. Intersphincteric abscess

See Also

• Anorectal Disorders