Mesenteric Adenitis

What is mesenteric adenitis?

Mesenteric adenitis means inflamed (swollen) lymph glands in the abdomen, which cause abdominal pain (tummy pain). It is not serious and will get better without treatment. Mesenteric adenitis is a fairly common cause of abdominal pain in children under 16 years, but is less common in adults.

The name comes from ‘mesentery’, which is the part of the abdomen where the glands are located, and ‘adenitis’ meaning inflamed lymph glands.

What are lymph glands?

Lymph glands (also called lymph nodes) occur throughout the body. They are normally pea sized. They are a major part of the immune system. During an infection, lymph glands swell and become painful while the immune system 'fights off' infecting germs. They go back to normal after the infection is over.

Most people are familiar with lymph glands in the neck that can swell when you have a sore throat or tonsillitis. In a similar way, it is the lymph glands in the abdomen, next to the intestines, that swell during a bout of mesenteric adenitis. (See separate leaflet called 'Lymph Glands Swollen' for more about lymph glands.)

What causes mesenteric adenitis?

Probably, an infection (germ) is what triggers the inflammation and swelling in the lymph glands. Most cases are probably due to a ‘virus’ infection such as a cold or sore throat. Less often, it may be a ‘bacterial’ infection that is the cause, for example, a bacterial infection in the intestine (gut). The inflamed glands then cause pain, tenderness and a high temperature.

What are the symptoms of mesenteric adenitis?

The symptoms are:

• Pain in the abdomen (tummy). The pain is usually located either in the centre of the abdomen, or in the lower right-hand side of the abdomen (known to doctors as the ‘right iliac fossa’).
• Fever (high temperature) and feeling generally unwell.
• Possibly, you may have some nausea and/or diarrhoea.
• You may have had a sore throat or symptoms of a cold, before the abdominal pain started.

How is mesenteric adenitis diagnosed?

Usually, it is diagnosed from your symptoms and a doctor’s examination. If you (or your child) have typical symptoms and there are no signs of anything else causing the pain, then your doctor may think that mesenteric adenitis is likely. It is difficult to actually prove the diagnosis, because the glands are deep in the abdomen and cannot be seen or felt. So the diagnosis involves excluding other problems which could cause this type of pain, and then making a presumed diagnosis of mesenteric adenitis.

Sometimes it is difficult to make a diagnosis or to rule out other problems. For example, mesenteric adenitis can imitate other causes of abdominal pain, such as appendicitis or ectopic pregnancy (there are separate leaflets on these conditions).

If the diagnosis is not clear, your doctor may suggest:

• A period of observation ('wait and see'), with a review after a few hours to see if symptoms have changed.
• A second opinion, for example, a referral to hospital for a surgeon's opinion.
• Tests to look for other conditions (see below).

Are any tests needed?

There are no specific tests for mesenteric adenitis. However, some tests may help in diagnosing other conditions which could be causing the pain. For example, blood tests, a urine test for infection, or scans (ultrasound or CT scan).

Note: If there is any possibility that you could be pregnant, a pregnancy test is essential. This is because a serious condition called 'ectopic pregnancy', which can occur in early pregnancy, may cause symptoms similar to mesenteric adenitis.

When might an operation be needed?

In some cases, problems such as appendicitis or ectopic pregnancy cannot be ruled out even after tests. If so, you may need an operation to look inside the abdomen and check for any suspected problem. Sometimes this can be done as a ‘laparoscopy’, where a thin fibre-optic telescope is used to look inside the abdomen.

If you have an operation or laparoscopy, then the inflamed glands may actually be seen. However, the purpose of the operation is not to look at the glands, but to ensure that other important problems are not missed.

What is the treatment?

No treatment is necessary, other than simple painkillers such as paracetamol or ibuprofen (if wanted). If a bacterial infection is suspected, you may be given antibiotics, but this is to treat the underlying infection rather than the mesenteric adenitis.

If your symptoms are getting worse, or last longer than two weeks, you should see a doctor urgently for a review.

What is the outlook?

The symptoms usually improve within a few days, and will almost always clear up completely within two weeks.