The medical term anal abscess consists of the words anal and abscess. Anal stands for "relating to the anus = anus" and abscess is generally a purulent inflammation caused by bacteria penetrating the tissue and spreading there. An anal abscess usually develops in the glands of the mucous membrane of the anal canal.
Anal abscesses are generally very painful and can cause the affected person to have a fever and feel very ill. In addition to the pronounced pain symptoms, redness, swelling and purulent secretions are suspicious signs of an anal abscess. Pus is a yellowish, creamy liquid that sometimes has a strong, unpleasant odor.
An anal abscess and an anal fistula are similar conditions, although they differ from each other in some details.
An anal fistulausually develops as a result of an anal abscess, namely when the pressure from the pus becomes so great that it seeks a way out. This creates new ducts in the tissue, which open either in the rectum (anal canal) or often on the surface of the skin. The opening of the fistula causes secretions, pus and sometimes feces to leak out. In many cases, this causes skin irritation and itching.
This mixture of pus, secretions and faeces can often also be seen in the underwear.
Once an anal fistula has formed, the pressure relief alleviates the symptoms for the person affected.
An anal abscess is the acute (= suddenly occurring), an anal fistula the chronic (= developing over a longer period of time) form of the same disease.
Moderate to severe pressure pain occurs in the abscess area, particularly when sitting or walking. Many of those affected suffer from sometimes very severe pain during bowel movements. Pain can also occur when pressure is applied to the swelling.
Due to the inflammation, the skin in the anus area is swollen and reddened. Some patients also suffer from fever and a deterioration in their general condition.
Different areas where anal abscesses can form © nmfotograf | AdobeStock
An anal abscess is usually diagnosed at a glance. Doctors, especially surgeons and specialists for diseases of the rectum(proctologists), usually do not need any further examinations to diagnose an anal abscess due to their experience. This applies in particular to abscesses that are located in the external anal area.
Internal abscesses and fistulas can also usually be suspected by inspection alone (medical term for looking). However, further examinations are necessary and helpful to confirm the diagnosis, including palpation of the anal canal, which can sometimes be painful and requires anaesthetic.
Other examination methods include rectoscopy of the anal canal, in which the mucous membrane is examined using a tubular device with a video function (rectoscope/proctoscope) and, if necessary, tissue samples and smears can be taken. This allows bacteria to be detected and malignant diseases (tumors) to be ruled out. However, a rectoscopy cannot be performed without anesthesia in the case of a painful anal abscess and is, so to speak, a minor surgical procedure. This is particularly true if the pus is drained and the fistula is split directly during the rectoscopy and visualization of the abscess.
As a rule, the treatment consists of opening the pus cavity and creating a generous drain. This allows the symptoms to subside quickly.
Depending on the severity, there are basically three different options for treating an anal abscess:
- Smaller anal abscesses can be treated with tar-containing ointments. These are applied to the affected area and draw the pus out of the wound.
- Larger anal abscesses can be treated with a puncture. Sterile cannulas or needles are used for this. The purulent contents are removed and the anal abscess shrinks. However, the risk of a new formation in the same or a neighboring area is high.
- In the case of large anal abscesses that are accompanied by severe symptoms, a surgical procedure is usually necessary. This involves opening the abscess cavity, draining the pus and splitting the fistula tract. This results in a larger wound area than with a puncture alone. Nevertheless, the pain usually subsides quickly as the pus can drain away and the pathogens (bacteria) are combated.
First, a local anesthetic is administered, or the entire procedure is performed under general anesthesia. The latter form of anesthesia is often necessary, as the anal region is an extremely sensitive area of the body.
During the operation, the epidermis is first cut, the underlying tissue is split and the abscess cavity is opened. A large part of the purulent secretion can already drain away at this point. If necessary, the remaining pus is then drained off via a drainage system .
Theadvantage of this method is that the bacterial pathogens responsible for the abscess are removed directly. There is no independent drainage inwards and the pathogens can no longer infect the surrounding area. This minimizes the risk of the bacteria entering the bloodstream and causing blood poisoning.
Once the secretion has been drained, the abscess cavity is cleaned, rinsed and any remaining inflamed tissue is removed.
In the case of particularly large anal abscesses, there is a risk of new purulent secretions forming , especially if the abscess cavity has not been sufficiently opened and purulent secretions can accumulate underneath again. In such cases, further surgery may be necessary.
The wound is not usually sutured after the operation. The wound heals from the inside out, which is also known as open wound healing. This measure prevents bacterial pathogens and remaining fluid from re-encapsulating. However, this open wound healing takes longer than primary wound healing, in which the wound edges are sutured directly.
During the first few days after the procedure, the wound must be rinsed and cleaned regularly, ideally daily. Dressings should therefore be changed at least once a day. In the case of heavily exuding wounds, the dressings often need to be changed several times a day. This is done in hospital by the attending doctors and nursing staff during ward rounds.
It is also important that the patient is instructed in how to care for the wound themselves. After the inpatient stay, patients should be able to carry out consistent wound toileting independently and without assistance. This is usually necessary until wound healing is complete and usually takes 3 to 6 weeks.
Sitz baths can have a positive influence on the healing process after surgery and accelerate healing.
The patient should shower the external wound regularly as long as it is open. It is also palpated during follow-up examinations to prevent premature adhesion. The wound is covered with dressings or compresses.
Post-operative pain is generally very slight. Depending on individual sensitivity, mild painkillers can alleviate the discomfort after the operation. If the stool consistency is firm, patients can take a mild laxative so as not to jeopardize wound healing through hard stools (constipation).
Patients do not have to follow a special diet after the operation. However, it is advisable to avoid excessive consumption of meat and fiber in the first few weeks after the operation. This enables the formation of a soft stool consistency.