Carrier rate in Sephardic Jews:
1 in 3 to 1 in 7 in North African Jews, Iraqi Jews, Armenians and Turks. It is estimated to be as high as 1 in 5 for Ashkenazi Jews, in whom the disease is much milder.

Disease frequency:
Approximately 1 in 200 for Sephardic Jews

Carrier rate in the general population:
Rare

Other ethnic groups in which it occurs:


Age of onset of symptoms:


Symptoms:
Episodes of fever, rash, difficulty breathing, arthritis and painful inflammation in the abdomen, chest or joints normally begin in childhood or early adolescence. These vary in severity and can last between 12 and 72 hours. Left untreated, amyloidosis can result in kidney failure, and fertility may be reduced. Stress and extreme physical exercise have been shown to precipitate attacks. There are no symptoms between episodes.

Average lifespan:
Lifespan is normal in individuals with the disorder, especially with management.

What causes the features of the disease:
White blood cells require a protein called pyrin (also known as marenostrin) to help regulate inflammation, which in turn is a site-specific process that fights infection and repairs tissue. When mutations on the MEFV gene reduce the amount of pyrin manufactured, the body loses control of the inflammation process, which is then prolonged or inappropriate to the body's condition. Familial Mediterranean fever (FMF) is an episodic condition which can also result in amyloidosis, or potentially dangerous buildup of protein in organs and tissues.

Treatment or management:
While the underlying cause of the disorder has no cure, the symptoms of inflammation can be managed with non-steroidal anti-inflammatory drugs (NSAIDs). Renal failure can be addressed with organ donation. A drug called colchicine, which prevents inflammatory attacks and amyloidosis, may be prescribed as well, though some affected individuals may not be responsive to this treatment.

Carrier testing - number of mutations screened for and detection rate in the Sephardic Jewish population:
Genetic testing of the MEFV gene can identify up to 80% of Iraqi Jewish carriers, 90% of Ashkenazi Jewish carriers and 95% of North African Jewish carriers.

Other testing information:
A physician knowledgeable of the symptoms can make a clinical diagnosis of FMF, or a simple blood test can be performed to check for mutations on the MEFV gene.

Current research:
Researchers are currently testing various treatments for FMF. Goto www.clinicaltrials.gov to learn more.

For more information:
National Organization for Rare Disorders:
   www.rarediseases.org