Anal Fissure management

Definition

Anal fissure is a longitudinal tear or ulcer in the anoderm distal to the dentate line, most commonly located in the posterior midline. It typically results from trauma caused by passage of hard stool, constipation, prolonged diarrhea, or increased anal sphincter tone. Secondary fissures may occur in association with conditions such as inflammatory bowel disease, tuberculosis, syphilis, HIV infection, or anorectal malignancy.

Clinical Presentation

Symptoms

• Severe sharp anal pain during defecation

• Pain persisting for minutes to hours after defecation

• Bright red rectal bleeding, usually noted on toilet paper or stool surface

• Constipation due to fear of painful bowel movements

• Pruritus ani (occasionally)

Signs

• Visible linear tear in the anoderm

• Sentinel skin tag (chronic fissure)

• Hypertrophied anal papilla

• Anal sphincter spasm and tenderness

Investigations

Usually Clinical Diagnosis

• Inspection of the anal region

Additional Investigations (if atypical or secondary fissure suspected)

• Proctoscopy/anoscopy

• Colonoscopy or sigmoidoscopy

• HIV testing

• Syphilis serology

• Evaluation for inflammatory bowel disease

• Biopsy of suspicious lesions

Non-Pharmacological Treatment

• Increase dietary fibre intake

• Adequate hydration

• Regular physical activity

• Sitz baths (warm water baths) for 10–15 minutes, 2–3 times daily and after defecation

• Avoid straining during bowel movements

• Maintain soft stool consistency

Pharmacological Treatment

Stool Softening and Constipation Management

A: Lactulose (PO) 15–30 mL 12-hourly, titrated to achieve soft stools

OR

A: Polyethylene glycol (PO) according to product instructions

Pain Relief

A: Paracetamol (PO) 500–1000 mg 6–8 hourly when required

Topical Therapy

S: Glyceryl trinitrate (GTN) 0.2–0.4% ointmentApply locally 12-hourly for 6–8 weeks

OR

S: Diltiazem 2% creamApply locally 12-hourly for 6–8 weeks

Local Anaesthetic (Short-term Symptom Relief)

A: Lidocaine 2–5% gelApply before defecation when required

Surgical Treatment

Indications:

• Persistent fissure despite 6–8 weeks of optimal medical therapy

• Chronic fissure with significant fibrosis

• Recurrent fissure

Procedures:

• Lateral internal sphincterotomy (gold standard)

• Botulinum toxin injection (where available)

Referral

Refer to a surgeon or colorectal specialist if:

• Symptoms persist despite medical treatment

• Recurrent fissures occur

• Secondary fissure is suspected

• Suspicion of malignancy or inflammatory bowel disease exists

Patient Education

• Maintain lifelong high-fibre diet and adequate hydration.

• Avoid prolonged straining and constipation.

• Seek medical attention for persistent bleeding, weight loss, or recurrent symptoms.