5-Minute Clinical Consult
Anal Fissure
To view the entire topic, please sign in or purchase a subscription.
Medicine Central™ is a quick-consult mobile and web resource that includes diagnosis, treatment, medications, and follow-up information on over 700 diseases and disorders, providing fast answers—anytime, anywhere. Explore these free sample topics:
-- The first section of this topic is shown below --
Basics
Description
Anal fissure (fissure in ano): longitudinal tear in the lining of the anal canal distal to the dentate line, most commonly at the posterior midline; characterized by a knifelike tearing sensation on defecation, often associated with bright red blood per rectum. This common benign anorectal condition is often confused with hemorrhoids; may be acute (<8 weeks) or chronic (>8 weeks) in duration
Epidemiology
- Affects all ages. Common in infants 6 to 24 months; not common in older children, suspect abuse, or trauma; elderly less common due to lower resting pressure in the anal canal
- Sex: male = female; women more likely to get anterior midline fissures (25%) versus men (8%)
Incidence
Exact incidence is unknown (1). Patients often treat with home remedies and do not seek medical care.
- 80% of infants, usually self-limited
- 10–20% of adults, most of whom do not seek medical advice.
- Lateral fissure: Rule out infectious disease.
- Atypical fissure: Rule out Crohn disease.
Etiology and Pathophysiology
High-resting pressure within the anal canal (usually as a result of constipation/straining) leads to ischemia of the anoderm, resulting in splitting of the anal mucosa during defecation and spasm of the exposed internal sphincter.
Genetics
None known
Risk Factors
- Constipation (25% of patients)
- Diarrhea (6% of patients)
- Passage of hard or large-caliber stool
- High-resting pressure of internal anal sphincter (prolonged sitting, obesity)
- Trauma (sexual activity or abuse, foreign body, childbirth, mountain biking)
- Prior anal surgery with scarring/stenosis
- Inflammatory bowel disease (Crohn disease)
- Infection (chlamydia, syphilis, herpes, tuberculosis)
General Prevention
All measures to prevent constipation; avoid straining and prolonged sitting on toilet.
Commonly Associated Conditions
Constipation, irritable bowel syndrome, Crohn disease, tuberculosis, leukemia, and HIV
-- To view the remaining sections of this topic, please sign in or purchase a subscription --
Basics
Description
Anal fissure (fissure in ano): longitudinal tear in the lining of the anal canal distal to the dentate line, most commonly at the posterior midline; characterized by a knifelike tearing sensation on defecation, often associated with bright red blood per rectum. This common benign anorectal condition is often confused with hemorrhoids; may be acute (<8 weeks) or chronic (>8 weeks) in duration
Epidemiology
- Affects all ages. Common in infants 6 to 24 months; not common in older children, suspect abuse, or trauma; elderly less common due to lower resting pressure in the anal canal
- Sex: male = female; women more likely to get anterior midline fissures (25%) versus men (8%)
Incidence
Exact incidence is unknown (1). Patients often treat with home remedies and do not seek medical care.
- 80% of infants, usually self-limited
- 10–20% of adults, most of whom do not seek medical advice.
- Lateral fissure: Rule out infectious disease.
- Atypical fissure: Rule out Crohn disease.
Etiology and Pathophysiology
High-resting pressure within the anal canal (usually as a result of constipation/straining) leads to ischemia of the anoderm, resulting in splitting of the anal mucosa during defecation and spasm of the exposed internal sphincter.
Genetics
None known
Risk Factors
- Constipation (25% of patients)
- Diarrhea (6% of patients)
- Passage of hard or large-caliber stool
- High-resting pressure of internal anal sphincter (prolonged sitting, obesity)
- Trauma (sexual activity or abuse, foreign body, childbirth, mountain biking)
- Prior anal surgery with scarring/stenosis
- Inflammatory bowel disease (Crohn disease)
- Infection (chlamydia, syphilis, herpes, tuberculosis)
General Prevention
All measures to prevent constipation; avoid straining and prolonged sitting on toilet.
Commonly Associated Conditions
Constipation, irritable bowel syndrome, Crohn disease, tuberculosis, leukemia, and HIV
There's more to see -- the rest of this entry is available only to subscribers.
