A blocked anal gland, a sexually transmitted infection (STI), or an infected anal fissure can cause anal abscesses. Some other risk factors include:
Toddlers or children that have a history of anal fissures (tears in the anal sphincter) are also at a higher risk for developing anal abscesses later on. Such anal fissures might occur in children who have a history of constipation.
You may have greater risks of getting anal abscess if you have:
Throbbing and constant pain in the anal area is probably one of the most common and immediately noticeable symptoms of anal abscess. The pain is usually accompanied by swelling in the anal area and greater pain during bowel movements.
Other common signs of an anal abscess include:
Some people may be able to feel a nodule or lump that’s red, swollen, and tender at the rim of the anus. Fever and chills can result from the infection. You may also have rectal bleeding or urinary symptoms such as difficulty urinating.
Anal abscesses may also occur deeper in the rectum, most often in those who have inflammatory bowel diseases. This can result in some pain or discomfort in the abdominal area.
In toddlers, there typically aren’t many symptoms other than signs of discomfort or pain, which may cause a child to become irritable. A lump or nodule may also be visible or felt around the anal area.
Anal abscesses are most often diagnosed through a physical exam where your doctor checks the area for characteristic nodules. You doctor will also check for pain, redness, and swelling in the anal area.
In some people, there may not be any visible signs of the abscess on the surface of the skin around their anus. You doctor will instead use an instrument called an endoscope to look inside the anal canal and lower rectum. Sometimes the abscess may be deeper than a physical exam can find. Then, you doctor may order an MRI or ultrasound to get a better look.
Further tests may be necessary to make sure Crohn’s disease isn’t a contributing factor. In these cases, a blood test, imaging, and a colonoscopy may be required. During a colonoscopy, your doctor will use a lighted, flexible scope to examine your colon.
Anal abscesses rarely go away without treatment. The most common and simple treatment is for your doctor to drain the pus from the infected area. This can usually be done in the doctor’s office. Your doctor will use medicine to numb the area. Any uncomfortable pressure should be relieved, allowing the tissue to begin to heal properly.
If anal abscesses are left untreated, they turn into painful anal fistulas that may require more surgical treatment. According to the American Society of Colon and Rectal Surgeons (ASCRS), about 50 percent of people who have an anal abscess will eventually develop an anal fistula. A fistula is an abnormal opening in the skin near the anus. A fistula generally requires surgery to fix the problem.
If there’s an extremely large anal abscess, surgery may be required. In some cases, a catheter may be used to make sure the abscess drains completely. Abscesses that have been drained are typically left open and don’t require stitches. If you have diabetes or a compromised immune system, your doctor may ask you to stay in the hospital for a few days to watch for any infection.
After surgery, it’s recommended you take warm (not hot) baths. Sitting in warm water will help reduce swelling and allow for more drainage the abscess.
Your doctor may also prescribe antibiotics if you have a compromised immune system or if the infection has spread.
There isn’t much known about how to prevent anal abscess. But there are some steps you can take, including:
Anal abscesses can cause complications, but they’re treatable. Understand the risk factors and make sure to closely monitor and manage any health conditions that may increase risk. If you notice anal problems, contact your doctor to get treatment and to prevent them from becoming worse.