Anal Fistula

An anal fistula is an abnormal passageway that develops from inside your anus to the skin outside. When anal glands become infected, drainage from the infection can create a fistula. This infection is called a perianal abscess. It’s more common in men.

SYMPTOMS

• Anal pain, often intense and throbbing, more while passing stool, cough, or sitting, and sensitive to touch.
• Swelling and redness inside or around the anus.
• Fluid drainage from somewhere around the anus. It may include pus, stool, or blood.
• Fever.
• Difficulty holding stool

CAUSES

• When your tissues are inflamed for a long time, due to an injury or disease.
• Chronic inflammation and infection can eventually erode into the nearby tissues, especially when pus needs to drain.
• Perianal abscess
• Inflammatory bowel diseases, such as Crohn’s disease.
• Sexually Transmitted Diseases.
• Tuberculosis of the anus.
• A traumatic injury or previous surgery in the anus.
• Radiation therapy for cancer in the pelvic region.
• Actinomycosis
• Inflammatory bowel disease (IBD) such as Crohn’s.

DIAGNOSIS

• MRI magnetic resonance imaging
• Endoscopic ultrasound.
• Fistulography
• Physical Examination

TYPES OF FISTULA

1. Inter sphincteric anal fistula: Passes through internal anal sphincter muscle and then burrows out through the space between internal and external sphincter muscles.
2. Trans sphincteric fistula: Travels through both layers of anal sphincter muscles.
3. Supra sphincteric fistula: Passes through the internal sphincter and then goes around the external sphincter.
4. Extra sphincteric fistula: Goes around both sphincter muscles. This less common type usually originates from the rectum rather than the anus, so it doesn’t come from an anal gland.
5. Superficial anal fistula: Travels from the lower part of the anal canal, below anal glands, through the skin nearby, bypassing muscles. This type doesn’t come from an anal gland.