Proctitis signs and symptoms may include:

• A frequent or continuous feeling that you need to have a bowel movement
• Rectal bleeding
• Passing mucus through your rectum
• Rectal pain
• Pain on the left side of your abdomen
• A feeling of fullness in your rectum
• Diarrhea
• Pain with bowel movements

Several diseases and conditions can cause inflammation of the rectal lining. They include:

• Inflammatory bowel disease. About 30 percent of people with inflammatory bowel disease (Crohn's disease or ulcerative colitis) have inflammation of the rectum.
• Infections. Sexually transmitted infections, spread particularly by people who engage in anal intercourse, can result in proctitis. Sexually transmitted infections that can cause proctitis include gonorrhea, genital herpes and chlamydia. Infections associated with foodborne illness, such as salmonella, shigella and campylobacter infections, also can cause proctitis.
• Radiation therapy for cancer. Radiation therapy directed at your rectum or nearby areas, such as the prostate, can cause rectal inflammation. Radiation proctitis can begin during radiation treatment and last for a few months after treatment. Or it can occur years after treatment.
• Antibiotics. Sometimes antibiotics used to treat an infection can kill helpful bacteria in the bowels, allowing the harmful Clostridium difficile bacteria to grow in the rectum.
• Diversion proctitis. Proctitis can occur in people following some types of colon surgery in which the passage of stool is diverted from the rectum to a surgically created opening (stoma).
• Food protein-induced proctitis. This can occur in infants who drink either cow's milk- or soy-based formula. Infants breast-fed by mothers who eat dairy products also may develop proctitis.
• Eosinophilic proctitis. This condition occurs when a type of white blood cell (eosinophil) builds up in the lining of the rectum. Eosinophilic proctitis affects only children younger than 2.

Risk factors for proctitis include:

• Unsafe sex. Practices that increase your risk of a sexually transmitted infection (STI) can increase your risk of proctitis. Your risk of contracting an STI increases if you have multiple sex partners, don't use condoms and have sex with a partner who has an STI.
• Inflammatory bowel diseases. Having an inflammatory bowel disease (Crohn's disease or ulcerative colitis ) increases your risk of proctitis.
• Radiation therapy for cancer. Radiation therapy directed at or near your rectum (such as for rectal, ovarian or prostate cancer) increases your risk of proctitis.

Proctitis that isn't treated or that doesn't respond to treatment may lead to complications, including:

• Anemia. Chronic bleeding from your rectum can cause anemia. With anemia, you don't have enough red blood cells to carry adequate oxygen to your tissues. Anemia causes you to feel tired, and you may also experience dizziness, shortness of breath, headache, pale skin and irritability.
• Ulcers. Chronic inflammation in the rectum can lead to open sores (ulcers) on the inside lining of the rectum.
• Fistulas. Sometimes ulcers extend completely through the intestinal wall, creating a fistula, an abnormal connection that can occur between different parts of your intestine, between your intestine and skin, or between your intestine and other organs, such as the bladder and vagina.