A perianal hematoma is a type of hematoma

Hematoma

A hematoma, or haematoma, is a localized collection of blood outside the blood vessels, usually in liquid form within the tissue. This distinguishes it from an ecchymosis, which is the spread of blood under the skin in a thin layer, commonly called a bruise...

 located in, or on the border of the anus

Anus

The anus is an opening at the opposite end of an animal's digestive tract from the mouth. Its function is to control the expulsion of feces, unwanted semi-solid matter produced during digestion, which, depending on the type of animal, may be one or more of: matter which the animal cannot digest,...

. It can be misdiagnosed as a hemorrhoid, but is sometimes referred to as an external hemorrhoid

Hemorrhoid

Hemorrhoids or haemorrhoids , are vascular structures in the anal canal which help with stool control. They become pathological or piles when swollen or inflamed. In their physiological state they act as a cushion composed of arterio-venous channels and connective tissue that aid the passage of...

.

Causes

Perianal hematoma are caused by the rupture of a small vein

Vein

In the circulatory system, veins are blood vessels that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated blood to the heart...

 that drains blood

Blood

Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....

 from the anus. This rupture may be the result of forceful or strained bowel movement or caused by heavy lifting, cough

Cough

A cough is a sudden and often repetitively occurring reflex which helps to clear the large breathing passages from secretions, irritants, foreign particles and microbes...

ing or straining. Once the rupture has formed, blood quickly pools within a few hours and, if left untreated, forms a clot.

Symptoms

The symptoms of a perianal hematoma can present over a short period of time. Pain, varying from mild to severe, will occur as the skin surrounding the rupture expands due to pressure. This pain will usually last even after the blood has clotted, and may continue for two to four days.

Management

If diagnosed within the first few hours of presentation, the pooling blood may be evacuated using a syringe

Syringe

A syringe is a simple pump consisting of a plunger that fits tightly in a tube. The plunger can be pulled and pushed along inside a cylindrical tube , allowing the syringe to take in and expel a liquid or gas through an orifice at the open end of the tube...

. Once the blood has clotted, removal by this method is no longer possible and the clot can be removed via an incision over the lump under local anesthetic. The incision is not stitched, but will heal very well. Care needs to be taken in regard to bleeding from the wound and possible infection with fecal bacteria. If left alone it will usually heal within a few days or weeks.

External links

• Perianal hematoma - MedBroadcast