A range of medical conditions have the potential to cause anal swelling. Among the most common culprits, however, are such conditions as anal bleeding; hemorrhoids; and anal tears, which are commonly referred to as fissures. Sometimes anal cysts can cause swelling in the area as well. Rectal abscesses may also be at fault in some cases.
Anal bleeding is one of the most common causes of swelling. Anal bleeding may come from the anus itself or may appear when blood is mixed with a person’s stools. There are many reasons a person may have bleeding from the anus, including inflammatory bowel disease, rectal cancer, constipation, and ulcers. An individual may also develop anal bleeding and swelling in relation to infections of the intestines and polyps.
Hemorrhoids may also cause anal swelling. Hemorrhoids are swollen veins that develop around a person’s anus. They often cause itching and pain in addition to swelling of the anus. A person may develop them for a number of reasons, including constipation, straining, and diets that do not contain enough fiber. Tumors that develop in the pelvis and pregnancy are also among the things that may contribute to the development of hemorrhoids.
Anal swelling also may be caused by anal fissures. An anal fissure is basically a tear in a person’s anus. A person may develop an anal fissure because of the repeated straining to have a bowel movement that often accompanies constipation or in relation to a condition called inflammatory bowel disease. Conditions such as Crohn's disease and ulcerative colitis may also contribute to the development of anal fissures. Less frequently, anal intercourse may cause a fissure.
Sometimes swelling develops because of abnormal lumps or masses that form in the area. For example, a person may develop an anal cyst that causes the swelling. An individual may also develop swelling of the anus because of an abscess. An abscess is a mass of pus that forms in an affected person’s body tissues. It is often surrounded by areas of inflammation.
In some cases, the causes of anal swelling are relatively minor and only appear temporarily. This is not always the case, however. Sometimes, the anal swelling may linger or develop because of a medical condition that requires treatment. For this reason, a person who notices swelling in this area may do well to seek an evaluation and advice from a medical professional he trusts.