What is an perianal/perirectal abscess?
A perianal/perirectal abscess is an infected cavity filled with pus found near the anus or rectum. Ninety percent of abscesses are the result of an acute infection in the internal glands of the anus. Occasionally, bacteria, fecal material or foreign matter can clog an anal gland and tunnel into the tissue around the anus or rectum, where it may then collect in a cavity called an abscess.
What symptoms will I have if I have an abscess around my anus or rectum?
Anorectal pain, swelling, redness of the skin around the anus, and fever are the most common symptoms of an abscess. Occasionally, rectal bleeding or urinary symptoms, such as trouble initiating a urinary stream or painful urination, may be present.
How is a perianal/perirectal abscess diagnosed?
A careful history regarding your symptoms and past medical history are necessary, followed by a physical examination. Your surgeon and Sacramento Colon & Rectal Surgery Medical group may suspect an abscess in this area if you have fever, redness, swelling, and tenderness when the area is touched; however, while most abscesses are visible on the outside of the skin around the anus, it is important to recognize that your doctor may not be able to identify the typical findings of an abscess, especially if the abscess is deeper. If you are having significant pain, especially during the exam, your doctor may still suspect an abscess and order additional tests to diagnose it.
What tests can help to diagnose an abscess?
Most abscesses are diagnosed and managed on the basis of clinical findings. Occasionally, additional studies can assist with the diagnosis, especially if the abscess is not clearly found on exam. Today, both traditional two-dimensional and three-dimensional endoanal ultrasound are a very effective manner of diagnosing a deep perirectal abscess or a more complex abscess. CT scans can be useful for patients with complicated infections or with other medical conditions which may present similarly, such as Crohn’s disease.
How is an abscess treated?
The treatment of an abscess is surgical drainage under most circumstances. An incision is made in the skin near the anus to drain the infection. This can be done in a doctor’s office with local anesthetic or in an operating room under deeper anesthesia. Hospitalization and antibiotics may be required for patients prone to more significant infections, such as diabetics or patients with decreased immunity.
Up to 50% of the time after an abscess has been drained, a tunnel (anal fistula [For Glacial, please place a hyperlink to the Anal Fistula page here]) may persist, connecting the infected anal gland to the external skin. This typically will involve some type of drainage from the external opening. If the opening on the skin heals when a fistula is present, a recurrent abscess may develop. Until the fistula is eliminated, many patients will have recurring cycles of pain, swelling and drainage, with intervening periods of apparent healing.
Antibiotics alone are a poor alternative to drainage of the infection. The routine addition of antibiotics to surgical drainage does not improve healing time or reduce the potential for recurrences in uncomplicated abscesses. There are some conditions in which antibiotics are indicated, such as patients with compromised or altered immunity or in the setting of extensive cellulitis (spreading of infection in the skin). The American Heart Association recommends the use of antibiotics for patients with prosthetic valves, previous bacterial endocarditis, congenital heart disease and heart transplant recipients with valvular pathology. A comprehensive discussion of your past medical history and a physical exam are important to determine if antibiotics are indicated.
What is a seton?
If at the time of draining your abscess an anal fistula (hyperlink to Anal Fistula page) is found, your surgeon may recommend the initial placement of a draining seton. This is often a thin piece of rubber or suture which is placed through the entire fistula tract and the ends of the seton (or drain) are brought together and secured, thereby forming a ring around the anus involving the fistula tract. The seton may be left in place for 8-12 weeks (or indefinitely in selected cases), with the purpose of providing controlled drainage, thereby allowing all the inflammation to subside and form a solid tract of scar along the fistula tract.
What is the recovery like from surgery?
Pain after surgery is controlled with pain medication (if needed), fiber, and water. Patients should plan for time at home using sitz baths and avoiding the constipation that can be associated with prescription pain medication. Often, patients are feeling much better within 2 weeks of abscess drainage.
Can the abscess recur?
As previously mentioned, up to 50% of abscesses may re-present as another abscess or as an anal fistula (hyperlink to Anal Fistula page). Should similar symptoms arise, suggesting recurrence, it is important that you contact your surgeon at Sacramento Colon & Rectal Surgery Medical Group so that we can guide you in what to do next.
Call the Sacramento Colon and Rectal Surgery Medical Group office near you to schedule a diagnostic evaluation for symptoms of an anal abscess, or book an appointment online today.