Diseases & Conditions

Familial Mediterranean fever

Familial Mediterranean fever is a rare disorder characterized by recurrent fevers and painful inflammation of your abdomen, lungs and joints.

Familial Mediterranean fever (FMF) is an inherited inflammatory disorder usually occurring in people of Mediterranean origin — including Sephardic Jews, Arabs, Armenians and Turks. But it may affect any ethnic group.

Familial Mediterranean fever is typically diagnosed during childhood. While there's no cure for this disorder, you may be able to relieve signs and symptoms of familial Mediterranean fever — or even prevent them altogether — by adhering to your treatment.

Signs and symptoms of familial Mediterranean fever usually begin during childhood. In fact, 90 percent of all people diagnosed with FMF are younger than 20 years old. The signs and symptoms, collectively referred to as "attacks," often occur with little warning. Generally, the attacks last two to three days, reaching peak intensity within the first 12 to 24 hours. Typical signs and symptoms may include:

• A sudden fever, ranging from about 100 F (37.8 C) to 104 F (40 C)
• Abdominal pain
• Recurrent chest pain
• Achy, swollen joints
• Constipation followed by diarrhea
• A red rash on your legs, especially below your knees

Less common signs and symptoms may include:

• Muscle aches
• Inflammation of the female reproductive organs (pelvic inflammatory disease)
• A swollen, tender scrotum
• Inflammation of your blood vessels (vasculitis)

Attacks usually occur sporadically, although some people report that vigorous exercise or stress provokes their attacks. Symptom-free periods may be as short as a week or as long as months. Between attacks, you'll likely feel normal.

When to see a doctor
See your doctor if you have a sudden fever accompanied by pain in your abdomen, chest and joints so that your doctor can determine the cause.

Familial Mediterranean fever is usually well controlled by the medication colchicine. If you're taking colchicine for FMF, consult your doctor if you experience any of the following:

• Diarrhea, nausea or vomiting. Side effects of colchicine are usually mild, but these signs and symptoms could indicate that your medication dose may need to be adjusted.
• Chronic pain. You may want to see a doctor who specializes in pain management if you have persistent pain that's not relieved by your medication.
• Ongoing attacks. If carefully adhering to colchicine therapy isn't preventing your attacks, talk to your doctor about other treatment options, such as dietary changes.

If you experience sudden worrisome signs or symptoms, such as shortness of breath or passing out, call 911 or emergency medical help.

The cause of familial Mediterranean fever is a gene defect on chromosome 16 (each person normally has 46 chromosomes, in 23 pairs). The gene, called MEFV, carries the genetic code for a protein called pyrin, which is involved in regulating inflammation. More than 50 different mutations in the MEFV gene have been identified — including one (M694V) that's found more frequently in Arabs and North African Jews. Although it's not certain exactly how this defect causes familial Mediterranean fever, it may be that people with this mutation don't make pyrin, hence, inflammatory responses aren't regulated and may be quite severe.

Familial Mediterranean fever is inherited as an autosomal recessive trait, meaning that you must inherit the mutated gene from each parent in order to develop the condition.

While there's no cure for familial Mediterranean fever, there is effective treatment. The most successful treatment for familial Mediterranean fever is a drug called colchicine.

Colchicine is a drug, usually taken as a pill, which reduces inflammation in your body. Some people might need to take just one dose a day, while others might require multiple doses to prevent attacks. People who are able to "predict" an impending attack are often able to stop those attacks before they start by taking colchicine. Taking colchicine after your symptoms appear, however, isn't effective.

Reducing the frequency and intensity
When you stick to your colchicine schedule, the drug will likely reduce the frequency and intensity of your symptoms. It also lowers your risk of complications, especially amyloidosis. Colchicine can cause side effects, such as pain, tingling or numbness in your hands or feet, or muscle weakness, especially in older men who are heavy drinkers or whose kidneys aren't functioning properly. However, colchicine therapy is generally considered safe, even when taken over the course of decades. If your symptoms are not controlled by colchicine, then interferon alpha, thalidomide, etanercept, infliximab or anakinra may be recommended.

In addition to colchicine therapy, you may find that the frequency and the severity of your symptoms lessen as you age or if you become pregnant. It's not certain why symptoms may improve at either of these times, but it may be related to changes in your immune system.