Anal and Rectal Lesions - Anal Fissure

Question 1

What are anal fissures?

Answer 1

Longitudinal/Elliptical tears of the squamous lining of the distal anal canal.

Question 2

Acute vs. chronic anal fissures.

Answer 2

Acute - Less than 6 weeks.

Chronic - More than 6 weeks.

Question 3

Risk Factors of anal fissures (4).

Answer 3

1. Constipation (main) - hard stool causes tears in the distal anal canal.
2. Inflammatory Bowel Disease.
3. STIs e.g. HIV, Syphilis, Herpes.
4. Pregnancy (especially after 3rd Trimester or after delivery).

Question 4

Clinical Feature of anal fissures.

Answer 4

1. Painful Bright Red PR Bleeding.
2. Severe Anal Pain/Tearing Sensation when Defecating.
3. Anal Spasms.
4. Skin Tag - Visible Sentinel Pile (Chronic).

Question 5

Positioning of anal fissures.

Answer 5

90% - Posterior Midline (6 o’clock) and sometimes 12 o’clock. If the fissures are found in alternative locations, other underlying causes should be considered e.g. Crohn’s.

Question 6

Management of Acute Anal Fissure (5).

Answer 6

1. Soften Stool (High-Fibre Diet + Bulk Forming laxative 1st Line).
2. Lubricants e.g. Petroleum Jelly before Defecation.
3. Topical Anaesthetics.
4. Analgesia.
5. Topical/Oral CCBs e.g. Dilitazem or Nifedipine.

Question 7

Management of Chronic Anal Fissure (3).

Answer 7

1. Continue Acute Management.
2. Topical GTN : 1st line treatment.
3. Secondary Care referral for sphincterotomy or Botulinum Toxin if topical GTN is not effective after 8 weeks.