Medicine - Anal Fissure

Anal Fissure 
​ESSENTIAL DESCRIPTION

Anal fissure (fissure in ano): a longitudinal tear in the lining of the anal canal distal to the dentate line, most frequently at the posterior midline; it is characterised by a feeling of tearing similar to a knife during faeces and is frequently accompanied by bright red blood per rectum. This common benign anorectal disease, which can be acute or chronic (lasting longer than 4 to 8 weeks), is sometimes mistaken for haemorrhoids; it may also be accompanied by hypertrophic papilla and sentinel piles (skin tags).


EPIDEMIOLOGY 
Impacts people of all ages. Older children are less likely to experience it because of decreased anal canal resting pressure, whereas infants between the ages of 6 and 24 months are most likely to experience it.
Males are more likely than females to develop anterior midline fissures (25%) compared to men (8%) in this study.
Incidence
Unknown occurrence is exact . Patients frequently treat themselves at home instead of going to the doctor.
80% of babies, who are typically self-limited; 10% to 20% of adults; most of whom do not seek medical help.
ALERT
Atypical and lateral fissures can rule out Crohn's disease and infectious diseases, respectively.

PATHOPHYSIOLOGY AND AETIOLOGY

Anoderm ischemia results in splitting of the anal mucosa during faeces and spasm of the exposed internal sphincter due to high resting pressure within the anal canal (often brought on by constipation/straining) and decreased circulation of the posterior canal.
Genomics Unknown

RISK FACTORS
Include diarrhoea (6% of patients) and constipation (25% of patients each).
Passage of large or hard-caliber stools; low fibre diet; and high internal anal sphincter resting pressure (excessive sitting; obesity);
 Prior anal surgery with scarring or stenosis Sexual activity or abuse Foreign body Childbirth Mountain biking Inflammatory bowel illness (Crohn disease) Infection (chlamydia, syphilis, herpes, tuberculosis).

GENERAL  PREVENTION

Take all necessary precautions to avoid constipation; stay off the toilet for an extended period of time.


Condition  often  associated  with Irritable bowel syndrome and constipation are located posteriorly, and HIV, leukaemia, TB, and Crohn's disease are located elsewhere or numerous places.


DIAGNOSIS AND PAST HISTORY 

Bright red blood on the stool or on wiping; severe, acute rectal discomfort that is occasionally accompanied by anal pruritus or perianal irritation.


MEDICAL ANALYSIS
A sensitive, smooth-edged tear in the anodermal tissue will be seen with gentle spreading of the buttocks and thorough inspection of the anal margin. This tear will often be posterior midline, sporadically anterior midline, and very infrequently eccentric to midline.
The unpleasant digital rectal exam and anoscopy can be postponed if examination supports the diagnosis.
Chronic fissures may have rolling edges, exposed muscle fibres, hypertrophic papillae at proximal end, and a sentinel pile (tag) at distal end. Minimal edoema, erythema, or bleeding may be detected. 


A lump at the anal margin that is swollen and uncomfortable is known as a thrombosed external haemorrhoid.
Perianal fistula: improper contact between the rectum and perianal epithelium with feculent or purulent drainage; Pruritus ani: shallow excoriations with erythema rather than real fissure; Perirectal abscess: sensitive, warm erythematous induration or fluctuance

Diagnostic tests and interpretation
Other diagnostic procedures
Avoid anoscopy/sigmoidoscopy at first unless it's required for other diagnoses or persistent fissures. Some individuals might need an exam under anaesthesia to confirm the diagnosis because of pain.


TREATMENT

By lowering the patient's high sphincter tone and treating its underlying cause, the treatment aims to prevent repeated tearing of the anal mucosa and the resulting spasm of the internal anal sphincter.

GENERAL  MEASURES

 Gently wash the area with warm water; eat a diet high in fibre; drink more water; take a daily fibre supplement; prevent constipation; keep a healthy weight.
 When necessary, medical treatment for chronic fissures is typically started in stages: Topical calcium channel blockers, nitrates, and injections of botulinum toxin

First Line: Medications 
50% of acute fissures will naturally heal with supporting interventions.
Stool softeners (docusate) taken orally every day; Osmotic laxatives (polyethylene glycol) taken orally every day as needed; Fibre supplements (psyllium, methylcellulose, inulin) taken orally every day and more fluid intake; Topical analgesics (2% lidocaine gel or 3% cream) applied 2 to 3 times daily for pain relief; Topical lubricants/emollients (Balneol lotion).
Next Line
Chronic fissures—will not heal without therapy because of ischemia and ongoing internal sphincter spasm:
Chemical sphincterotomy: Topical nitroglycerin 0.2-0.4% ointment applied BID; nitroglycerin 0.4% ointment commercially available (Rectiv): slightly but significantly better than placebo in healing (48.6% vs. 37%); late recurrence common (50%); lowers resting anal pressure through the release of nitric oxide and vasodilation. Significant side effects (20–30%) include headache, hypotension, and dizziness.
- Topical calcium channel blockers (diltiazem 2% ointment, nifedipine 0.2-0.3% gel), when given 2–4 times daily, relax the internal sphincter muscle and lower the resting anal pressure; they are not any more effective than nitrates for healing but have less adverse effects. Oral calcium channel blockers have similar rates of recurrence, higher adverse effects, and lower rates of healing.
- A 4 mL (20 unit) injection of botulinum toxin (Botox) into the internal sphincter muscle does not speed up healing any more than topical nitrates but has less adverse effects. It also prevents the release of acetylcholine from nerve endings, which reduces muscle spasm.In one small randomised controlled experiment, minoxidil 5% gel outperformed topical glyceryl trinitrate in terms of improving and speeding up the healing of chronic fissures.

QUESTIONS FOR REFERENCE

 Persistent symptoms despite medicinal treatment; this is often attempted for 90 to 120 days prior to referral for colorectal surgery. Due to their demonstrated higher healing rates, some chronic fissure patients may be sent immediately for surgical therapy.
 Late recurrence, which is frequent (50%) and is more likely if the underlying condition (constipation, irritable bowel) is not treated
Secondary fissures (possible inflammatory bowel disease or an infectious condition)

ADVANCED THERAPIES

Chronic fissures may benefit from anococcygeal support, a customised toilet seat, in order to prevent surgery.


SURGICAL AND OTHER PROCEDURE

Surgery is normally only performed when other treatments have failed.
The preferred surgical method (LIS), which involves dividing the internal sphincter muscle, has a recovery rate of 95%.
- Up to 47% in the short term and 15% in the long term are the risks for faecal or flatus incontinence .
- Both open and closed strategies produce comparable outcomes and are acceptable.
- Can be repeated with comparable results for recurrent fissures
- Faecal incontinence with or without obstetrical harm as a result of increased risk makes this procedure uncommon for women who are capable of becoming pregnant.
Less incontinence but slower healing rates are associated with anocutaneous flap, a safe substitute for LIS in individuals without anal hypertonia. Botulinum toxin injections are a first-line option as well; they are less successful than surgery (60-80% recovery) but have less side effects - Short-term risk of faecal or flatus incontinence: 18%; no long-term risk.
- Low dosages are just as effective as higher doses, and they have a decreased risk of side effects like incontinence and recurrence. They can be repeated as needed with the same effectiveness.
- Fissurectomy and higher doses may be as efficient as surgical sphincterotomy.
If surgical referral is not possible, gastroenterologists may utilise controlled pneumatic balloon dilation; nevertheless, this treatment should not be used as a first option because its benefits are not well established. Manual dilation that is not under control is no longer advised.

ALTERNATIVE & COMPLEMENTARY MEDICINE
Prior to being suggested as first-line therapy, alternative therapies (such as hibiscus and other herbal extracts, clove and coconut oil, essential oils, homoeopathic and ayurvedic drugs, and anal self-massage) require more research.

CONTINUAL CARE DIET

High fibre intake (more than 25 grammes per day; supplement with daily fibre supplements); increase fluid intake; reduce caffeine.

EDUCATION OF PATIENTS

Avoid sitting for too long or straining during bowel motions. Drink enough of water to prevent constipation.
Avoid applying triple antibiotic ointment and steroid creams to the anal area for an extended period of time.
To reduce side effects, apply the first dose of nitroglycerin ointment before going to bed. Topical drugs should be administered directly to the anal verge; there is no need to inject rectally.

PROGNOSIS
The majority of acute fissures recover with conservative therapy in 6 weeks. Medical therapy should still be used as the first line of treatment even though it has a 40% failure rate for treating chronic anal fissures.

COMPLICATIONS
A chronic fissure is a side effect of an acute fissure that does not heal.
Recurrence is a frequent side effect, particularly when the underlying reason is not treated.
Less frequent consequences include abscess and fistula formation.
The main cause of faecal and flatus incontinence is surgery (5–47% postoperatively), and it can last a lifetime (up to 8%, largely due to flatus).