Mesenteric lymphadenitis is an inflammation of the lymph nodes in the fold of membranes that attaches organs, such as your colon, to your abdominal wall (mesentery). Mesenteric lymphadenitis occurs mainly in children and adolescents.

Commonly caused by a viral or bacterial infection, mesenteric lymphadenitis may mimic the signs and symptoms of appendicitis. Unlike appendicitis, however, mesenteric lymphadenitis usually requires no treatment.

Signs and symptoms of mesenteric lymphadenitis may last a few days or as long as a few weeks. They include:

• Abdominal pain, often centered on the lower, right side, but the pain can be more diffuse
• Fever

Depending on what's causing the ailment, other signs and symptoms may include:

• Diarrhea
• Nausea and vomiting
• General unwell feeling (malaise)

The most common cause of mesenteric lymphadenitis is a viral infection, such as adenovirus, a common cause of intestinal infection (gastroenteritis) in children. But it can also result from a bacterial infection. The type of bacterium commonly associated with mesenteric lymphadenitis is yersinia, which may come from eating undercooked pork or drinking unpasteurized milk or contaminated water.

Some children may develop an upper respiratory infection before or during their course of mesenteric lymphadenitis. Other conditions associated with inflamed mesenteric nodes include:

• Epstein-Barr virus (EBV) — one of the most common human viruses
• Cat-scratch fever — a bacterial infection from a cat scratch or bite

The signs and symptoms of mesenteric lymphadenitis usually resolve on their own within a few days to a few weeks. However, it may be important for your child to see a doctor to rule out appendicitis and other possible causes of abdominal pain. Take your child to a doctor if fever, low blood pressure (hypotension), bloody stools or inability to keep fluids down accompany the abdominal pain.

Your doctor is likely to take your child's medical history and ask when and how signs and symptoms developed. In addition, your doctor may request laboratory tests to help pin down the diagnosis, including:

• Blood tests. Certain blood tests can help determine whether your child has an infection and what type of infection it is.
• Imaging studies. A computerized tomography (CT) scan of your child's abdomen can help differentiate between appendicitis and mesenteric lymphadenitis. Abdominal ultrasound also may be used.

Mesenteric lymphadenitis usually resolves on its own and rarely causes complications. However, if the cause is a bacterial infection and it isn't treated, the infection could spread to the bloodstream, causing an overwhelming infection (sepsis). Sepsis may result in organ failure and death. Treatment of sepsis involves hospitalization and administration of antibiotics through a vein (intravenously).

Mild, uncomplicated cases of mesenteric lymphadenitis and those caused by a virus usually resolve on their own within days or weeks. To help ease discomfort, over-the-counter (OTC) pain relievers and fever reducers may help.

If your child has a bacterial infection that's causing moderate to severe signs and symptoms, your doctor may prescribe antibiotics.

For the pain and fever of mesenteric lymphadenitis, have your child:

• Get plenty of rest. Adequate rest can help your child recover.
• Drink fluids. This can help prevent dehydration from vomiting or diarrhea.
• Take OTC pain relievers. These include ibuprofen (Advil, Motrin, others) and acetaminophen (Tylenol, others). Don't give your child aspirin without consulting your doctor because of its link to Reye's syndrome in children. Reye's syndrome is a rare but serious illness that can affect the blood, liver and brain of children and teenagers recovering from a viral infection.