Introduction

A small tear in the lining of the anus—muscular opening at the end of the digestive system tract where stool exits the body—is known as an anal fissure. Anal fissures are common in individuals with a history of constipation or passing hard stools. Anal fissures may result from a low-fibre diet, trauma, or previous anal surgery.

Anal fissures can be either acute (lasting less than six weeks) or chronic (more than six weeks) and typically occur at the posterior or anterior midline. Treatments will range from dietary adjustments to topical medications and even surgical intervention in the worst cases.¹

Stress is a reaction experienced by an individual physically or emotionally in response to a stressor. There are 2 types of stressors: internal stressors (connected to a disease) or external stressors (related to the immediate surroundings).

In this article, we are going to discuss the causes of anal fissures, the symptoms, and how they are diagnosed. In addition, we will learn the relationship between the anal fissure and stress.

Causes of anal fissures

The National Institute for Health and Care Excellence (NICE) estimates the annual incidence of anal fissures to be 1.1 incidents per 1,000 person-years. Although it can occur at any age and sometimes even in young children with poor toileting habits, anal fissures most often affect those between the ages of 15 and 40.

Anal fissures can be caused by a variety of factors, including the following:¹

Physical factors

• Constipation
• Chronic diarrhoea
• Sexually transmitted diseases
• Tuberculosis
• Inflammatory bowel disease
• HIV
• Anal cancer
• Childbirth
• Previous anal surgery
• Anal sexual intercourse
• Anal injury due to penetration
• Increased pressure from an elevated anal sphincter tone as a prolonged straining during a defecation

Dietary influences

• Passing hard stools often due to a low-fibre diet
• Lack of drinking enough water
• There are types of food that make it hard to pass through the digestive tract system

Physiological connection between stress and anal fissures

Stress can cause or worsen symptoms, and vice versa, making the relationship between stress and digestive problems complicated and two-way.

Stress-induced changes in gut motility

Our body's sympathetic nervous system gets activated by acute stress, which results in the release of noradrenaline, also known as norepinephrine, from the stomach. This hormone reduces the production of acetylcholine, an essential neurotransmitter, which in turn slows intestinal motility. Research suggests that noradrenaline helps regulate our gut during and following stressful situations.²

Catecholamines, such as epinephrine (also known as adrenaline) and norepinephrine, released during stress affect the gastrointestinal (GI) system. By turning on α-adrenergic receptors in the smooth muscles of the intestines, these hormones delay gastric emptying and reduce the intestinal motility when you are stressed.

Stress-induced changes in gut motility can manifest as diarrhoea or constipation, whereas increased visceral sensitivity may contribute to symptoms such as irritable bowel syndrome.³

Stress-related hormonal changes affecting digestion

Corticotropin-releasing factor (CRF) and related peptides affect the activity of the enteric nervous system (ENS)—controls the digestive system—thereby regulating the GI tract's stress response. In addition, the stomach muscles contract as a result of CRF and other released immune-modulating chemicals (e.g., interleukin-6).²

Stress also causes the production of catecholamines like norepinephrine and adrenaline, which attach to adrenergic receptors located throughout the gastrointestinal system and affect several physiological functions. By activating α-adrenergic receptors, the blood circulatory system of the gastrointestinal system becomes constricted, preventing blood flow to the stomach, hence, preventing gastrointestinal secretions and nutritional absorption.³

Stress weakens the barrier between the body and the insides of your intestines—the gastrointestinal mucosal barrier. A weakened GI mucosal barrier’s integrity increases its permeability, making people more vulnerable to infection and inflammation.

Stress-induced dysregulation of the gut-brain axis worsens digestive disorders and may exacerbate symptoms by increasing the exchange of information between the gut microbiota and central nervous system (CNS). Gastrointestinal dysfunction may also be exacerbated by changes in the variety and composition of the gut microbiota brought on by stress.³

Symptoms of anal fissure

There is a group of symptoms that differs from person to person, but this is a common presentation, which includes the following:

Pain at defecation

• Sharp or burning pain at the time of passage of stool is the common presentation
• Uncomfortable pain, although the pain's intensity varies

Pain after defecation

The pain usually persists for some minutes to hours after defecation.

Bright red blood on stool or toilet paper

• Fresh, bright red blood may be seen on the surface of the stool
• Blood may also be present on toilet paper or in the toilet bowl after the passing of stools. This type of bleeding is usually painless but can be frightening

Visible fissure in skin around the anus

A small tear or fissure in the skin may be seen on close inspection of the anus.

Small lump or skin tag next to the anal fissure

• A small, raised area or skin tag may form beside the fissure
• The growth usually is a reaction to persistent inflammation or other kinds of irritation and thus is tender to touch

Diagnosis of anal fissure

When you visit your healthcare provider with symptoms of an anal fissure, he will begin by getting a history and examining you. Normally, it involves a gentle inspection of the anal region; the tear is almost always apparent, thus easily diagnosable.

A recent fissure is like a paper cut and is just a fresh tear, whereas a chronic one, persisting for more than eight weeks, is much deeper and may form internal or external fleshy growths. The position of the fissure may also sometimes provide clues to the cause.

Therefore, fissures on the sides of the anus, rather than the front or back, may sometimes be indicative of general underlying diseases like Crohn's disease and thus require further investigation.

To determine if there are any underlying conditions, your healthcare provider may recommend additional tests, including:

Anoscopy

It involves the introduction of a tubular instrument, known as an anoscope, into the anus. Anoscopy allows the provider to visualise the rectum and anal canals.

Flexible sigmoidoscopy

A long, thin, flexible tube having a small video camera fitted into it is inserted into the rectum and lower part of the colon (sigmoid colon). Flexible sigmoidoscopy is often suggested for patients less than 45 years with no risk factors for intestinal diseases or cancer of the colon (large intestine).

Colonoscopy

Colonoscopy is a flexible tube inserted into the rectum to investigate the whole of the colon. It is usually recommended for people above the age of 45, those with risk factors for colon cancer, and those who report other symptoms, like abdominal pain or diarrhoea.

These diagnostic tests ensure that any underlying diseases that might be predisposing to the fissure are identified and managed appropriately.

Treatment options

There are multiple choices that your doctor can offer, including:⁴

Treatments for symptom relief

The measures for symptom relief include sitz baths, dietary modifications, local ointments, and self-anal massage.

Sitz bath

• Improves perineal hygiene
• Relaxes internal anal sphincter
• Decreases pain

 Local anaesthetics

Commonly, lignocaine, a local anaesthetic, is used for a short term due to the risk of skin sensitisation.

Anal self-massage

• Promotes sphincter relaxation
• Recommendation: 10 minutes twice daily initially, followed by circular motion for another 5 days

Passive dilation

Using graduated anal dilators (cylindrical tools to increase the diameter of the anal passage) has been shown to enhance fissure resolution.⁵

Anal sphincter relaxation

The internal anal sphincter dilation can be achieved by chemical or mechanical means.

Chemical sphincterotomy

Topical nitrates like Glyceryl trinitrate (GTN) are the first-line treatments for chronic anal fissures (CAF). The common dose is 0.2%, applied two to three times daily. 

The side effects are vasodilation and severe headaches (20% discontinuation rate).

Calcium channel blockers (CCBs)

• Nifedipine dosing: 0.3-0.5%, healing rate 93%
• Diltiazem dosing: 2%, healing rate 80.4%. The observed side effect is pruritus ani (10% of patients)
• Minoxidil is equally effective as diltiazem. The recommended therapy duration: 6-8 weeks

Botulinum toxin (BT)

• Botulinum toxin temporarily paralyses muscles, reducing pain and promoting healing
• Healing rates: 60-80%; recurrence up to 42%
• Side Effects: Transient bowel (up to 5%) and flatus incontinence (up to 18%)
• Can be performed as an office-based procedure or outpatient with sedation
• Effects wear off after 3 months (approximately); underlying issues must be addressed to prevent recurrence

Surgery

Surgery may be recommended if chronic anal fissures do not respond to the above-mentioned treatments or if the symptoms are very severe.

Surgery can include the common procedure known as lateral internal sphincterotomy, whereby a small part of the anal sphincter muscle is cut (incised) to promote healing and reduce spasms with attendant pain.

Lifestyle modifications

Making certain lifestyle changes can alleviate discomfort, promote the healing of an anal fissure, and reduce the likelihood of recurrence. Consider the following adjustments:

Increase fibre intake

To maintain soft stools and promote fissure healing, aim for 25 to 35 grammes of fibre per day. Fibre-rich foods include fruits, vegetables, nuts, and whole grains. Fibre supplements are also an option. Gradually increase your fibre intake to minimise bloating and gas.

Stay hydrated

Consuming adequate water helps in preventing constipation, which can worsen or cause fissures.

Avoid straining during bowel movements

Straining increases pressure on the anal area, which can reopen a healing fissure or cause a new one.

Stress management techniques

Stress management techniques include different psychological approaches to effectively alleviate stress.

Cognitive-behavioural therapy (CBT)

CBT helps reframe negative thought patterns and develop healthier responses to stressors by:⁶

• Focusing on apparent control, experience avoidance, and self-focused concentration
• Encouraging viewing experiences as unique and new

Mindfulness and relaxation techniques

The techniques, such as meditation and yoga, promote present-moment awareness and reduce automatic stress reactions.⁷

Counselling and support groups

Counselling and support groups offer emotional support, allowing individuals to share experiences and gain insights.⁶ 

FAQs

What does an anal fissure look like?

It is a small tear in the anal lining.

Can a fissure heal on its own?

In some cases, it can be healed by lifestyle modifications.

Summary

Anal fissures usually result from constipation and trauma and produce severe discomfort at the time of defecation, which is associated with bleeding. Principles of good management would therefore include dietary modifications, medications, and stress-reducing techniques that will enhance healing and prevent recurrence. During this, an interprofessional care team plays an important role in managing and improving long-term outcomes for patients who have an anal fissure.