An anorectal, anal or perianal abscess is the formation of a cavity filled with pus in the skin 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 elimination of a yellowish secretion.
Generally, the abscess results from the clogging of the glands in the anus region 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 symptoms of anorectal abscess, 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 a coloproctologist.
Main symptoms
The main symptoms of anorectal abscess include:
- Pain in or near the anus region, especially when evacuating or sitting;
- Lump in the anal region;
- Skin redness;
- Calor no local;
- Swelling;
- Increased sensitivity on site;
- Fever;
- Bleeding;
- Output of pus.
When the abscess ruptures, with pus escaping from its interior, there may be relief of symptoms, especially pain. However, when symptoms persist, return or there is frequent discharge of pus, it may indicate the presence of other diseases or the absence of improvement in the abscess. In these cases, it is recommended to consult a doctor. Check out the main causes of pain when evacuating.
How to confirm the diagnosis
The diagnosis is usually made by the doctor by evaluating the symptoms and analyzing the anus region.
However, in some cases exams such as anoscopy, ultrasound, computed tomography or magnetic resonance imaging may still be necessary. Blood tests, such as a blood count, can also help assess the severity of the infection.
Possible causes
Perianal abscess is caused by a bacterial infection, generally due to blockage 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;
- Hidradenitis suppurativa;
- Infections of the rectum, such as amoebiasis, lymphogranuloma venereum, tuberculosis or rectal schistosomiasis;
- Anal fissure;
- Anorectal cancer;
- Trauma;
- Presence of a foreign body in the region;
- Compromised immunity;
- Sequel to chemotherapy treatment;
- 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 carried out
Depending on the depth of the abscess, its size, the severity of the infection and the risk for widespread infection, treatment may involve:
1. Drainage through surgery
The main form of treatment for anal abscess is drainage of the pus, which must 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 require hospitalization 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 painkillers and taking sitz baths with warm water, due to their anti-inflammatory effect. It is important that the entire recovery is monitored by a doctor to ensure that the abscess has improved and that there are no complications.
2. Use of antibiotics
The use of antibiotics should always be advised by a doctor, and is generally indicated in addition to drainage when the abscess is large, has an extensive area of redness and heat, or if there is a risk of generalized infection, such as in the case of diabetes, compromised immunity or obesity, for example.
3. Treatment of associated changes
Sometimes there may be a fistula related to the abscess. This fistula is a channel that can appear after the exit of pus, or due to other diseases, and can hinder the improvement of the infection. In these cases, treatment of the abscess must also include 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 doesn’t get better
If the abscess does not improve, it is recommended to consult a doctor, because after draining an anorectal abscess, healing may fail and a fistula may form, which may be responsible for the persistence or return of symptoms such as perianal swelling and secretion.
Furthermore, in some cases the abscess may return, which is more common during the first year after initial treatment.
Possible complications
In some cases, the abscess can give rise to an anal fistula, the route of which 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 impairment of the anal sphincter, causing fecal incontinence, or a necrotizing infection, which is when bacteria reach neighboring tissues, such as skin, muscles and fat.
Furthermore, if the treatment is not carried out correctly, it is possible for bacteria to reach the bloodstream and cause a generalized infection, which can even lead to death.
