Anus

Rectal abscess is an inflammatory process around the rectum that involves the formation of a pus-filled abscess.
In about 90% of cases, it is caused by an obstruction or bacterial infection of the glands that open into the rectum.
Inflammation and then pus formation can spread from the blocked, infected glands in different directions.
Abscesses are classified according to their localisation.
We distinguish between abscesses near the anus, between the anal sphincters, between the rectum and the ischium and above the pelvic floor.
The most common of these is the anal abscess and the least common is the upper pelvic abscess.
In the remaining 10% of cases, the underlying cause is not a blockage of the glands, but an inflammatory bowel disease, sexually transmitted disease, trauma, foreign body, cancer or immunosuppressed condition.

The classic symptoms of rectal abscess are constant throbbing pain, swelling and redness in the rectal area.
The symptoms may also be accompanied by constipation, urinary dysfunction, fatigue, chills or even fever.
The pain is often so intense that the patient is unable to sit up or sleep at night.
If the abscess bursts spontaneously, pus may be seen around the rectum.

The diagnosis of anal abscesses, as well as those between the rectum and the ischium, can usually be made clearly on the basis of the patient’s history and physical examination.
In our clinic we have the possibility to confirm the diagnosis by ultrasound examination.
In the case of subcutaneous abscesses near the anus, we can determine the exact location and extent of the abscesses by ultrasound examination with a linear probe, while in the case of abscesses between the anal sphincter rings or higher, we can determine the exact location and extent of the abscesses by endoanal 3D rectal ultrasound examination.
If an abscess above the pelvic floor is suspected, 3D rectal ultrasound should be complemented by a pelvic CT or MR scan.

Once the diagnosis has been made, surgical exploration of the abscess is always necessary as soon as possible.
Depending on the location and extent of the abscess and the patient’s subjective complaints, this may be done under local anaesthesia or anaesthesia.
During the procedure, the abscess is opened, the pus is drained, the abscess cavity is thoroughly irrigated and the wound created is left open to allow the cavity to drain further and the surrounding inflammation to reduce over the coming days.
The wound will continue to heal from the wound bed and edges, and until fully healed, the wound will need to be showered thoroughly with lukewarm water several times a day!