Anorectal abscess: what é, symptoms, causes and treatment

2023 Author: Benjamin Dyson | [email protected]. Last modified: 2023-05-21 01:37

The anorectal, anal or perianal abscess is the formation of a cavity filled with pus in the skin of the region around the anus, which can cause symptoms such as pain, especially when defecating or sitting; appearance of a painful lump in the anal region; bleeding or passing a yellowish discharge.

Usually, the abscess results from the clogging of the glands that exist in the region of the anus followed by the development of bacteria, which leads to the formation of this cavity and pus. However, some diseases such as cancer and inflammatory bowel disease may also be involved, facilitating the formation of anorectal abscess.

In the presence of anorectal abscess symptoms, especially if associated with immunity problems or signs of infection such as fever and swelling with redness, it is important to consult a general practitioner or coloproctologist.

Main symptoms

The main symptoms of anorectal abscess include:

• Pain in or near the anus, especially when defecating or sitting;
• Lump in the anal region;
• Redness of the skin;
• Local heat;
• Swelling;
• Increased sensitivity on the spot;
• Fever;
• Bleeding;
• Outlet of pus.

When the abscess ruptures, with the pus coming out of it, there may be relief from symptoms, especially pain. However, when symptoms persist, return or there is frequent leakage of pus, it may indicate the presence of other diseases or the absence of improvement of the abscess. In these cases, it is recommended to consult a doctor. Check out the main causes of pain when having a bowel movement.

How to confirm the diagnosis

The diagnosis is usually made by the doctor through the evaluation of symptoms and analysis of the anus region.

However, in some cases, tests such as anoscopy, ultrasound, computed tomography or magnetic resonance imaging may still be necessary. Blood tests, such as a complete blood count, can also help assess the severity of the infection.

Possible causes

Perianal abscess is caused by a bacterial infection, usually due to clogging of the glands that produce mucus in the anal region.

However, there are some conditions that increase the risk of an abscess forming, such as:

• Inflammatory bowel diseases such as Crohn's disease or ulcerative colitis;
• Suppurative hydradenitis;
• Infections of the rectum, such as amoebiasis, lymphogranuloma venereum, tuberculosis, or rectal schistosomiasis;
• Anal fissure;
• Anorectal cancer;
• Immunity compromised;
• Having undergone surgery in the anorectal region, such as hemorrhoidectomy, episiotomy or prostatectomy, for example.

These conditions cause inflammation in the tissue of the rectum and anus, facilitating the accumulation of bacteria and the formation of pus. Better understand the causes, symptoms and treatment of proctitis.

How the treatment is done

Depending on the depth of the abscess, its size, the severity of the infection and the risk for generalized infection, treatment may involve:

1. Drainage through surgery

The main form of treatment for anal abscess is drainage of pus, which should be done as soon as possible to reduce the risk of a more serious infection.

This procedure can be performed by a general practitioner, under local anesthesia and without the need for hospitalization, in cases of more superficial and smaller abscesses. However, more complicated cases need to be hospitalized so that drainage can be performed in the operating room by a general surgeon or coloproctologist.

After drainage, the doctor may recommend rest, use of analgesics and sitz baths with warm water, due to its anti-inflammatory effect. It is important that the entire recovery is accompanied by a doctor to make sure that the abscess has improved and that there are no complications.

2. Use of antibiotics

The use of antibiotics should always be guided by a doctor, and is usually indicated in addition to drainage when the abscess is large, presents an extensive area of redness and heat, or if there is a risk of generalized infection, as in the case of diabetes, compromised immunity or obesity, for example.

3. Handling associated changes

Sometimes there may be a fistula related to the abscess. This fistula is a channel that can arise after the pus comes out, or due to other diseases, and can hinder the improvement of the infection. In these cases, the treatment of the abscess must also include the treatment of the fistula, which can be done through surgery or by placing a material inside the fistula to stimulate its closure. Understand better what anal fistula is and how to treat it.

What to do if the abscess does not improve

In case the abscess does not improve, it is recommended to consult a doctor, because after drainage of an anorectal abscess there may be a failure in healing and formation of a fistula, which may be responsible for the persistence or return of symptoms such as perianal swelling and secretion outlet.

Also, in some cases the abscess may return, which is more frequent during the first year after initial treatment.

Possible complications

In some cases, the abscess can give rise to an anal fistula, whose path can go from the anus to the vagina, uterus, urinary tract or other parts of the intestine, for example.

Other complications that an anal abscess can cause are the involvement of the anal sphincter, causing fecal incontinence, or a necrotizing infection, which is when bacteria reach neighboring tissues, such as skin, muscles and fat.

In addition, if the treatment is not done correctly, it is possible that the bacteria reach the bloodstream and cause a generalized infection, which can even lead to death.