Familial Mediterranean Fever

What is familial Mediterranean fever?

Familial Mediterranean fever is an inherited condition characterized by recurrent episodes of painful inflammation in the abdomen, chest, or joints. These episodes are often accompanied by fever and sometimes a rash. The first episode usually occurs by the age of 20, but in some cases, the initial attack occurs much later in life. Typically, episodes last 12 to 72 hours and can vary in severity and length of time between attacks. A buildup of protein deposits (amyloidosis) occurs in some cases of familial Mediterranean fever and can lead to kidney failure if left untreated.

How common is familial Mediterranean fever?

Familial Mediterranean fever primarily affects populations originating in the Mediterranean region, particularly people of Armenian, Arabic, Turkish, and Jewish ancestry. The frequency of affected individuals in these populations ranges from 1 in 250 people to 1 in 1,000 people. This disorder is less common in other populations.

What genes are related to familial Mediterranean fever?

Mutations in the MEFV gene cause familial Mediterranean fever.

Normal variations in the SAA1 gene modify the course of familial Mediterranean fever.

The MEFV gene provides instructions for making a protein called pyrin (also known as marenostrin), which is found in white blood cells. This protein probably helps to limit or stop the inflammation process. Mutations in the MEFV gene can lead to reduced activity of the pyrin protein, which disrupts control of the inflammation process. With impaired control, an inappropriate or prolonged inflammatory response can occur, usually accompanied by fever and pain in the abdomen, chest, or joints.

Some evidence suggests that a particular version of the SAA1 gene (called the alpha variant) may increase the risk of amyloidosis among people with familial Mediterranean fever.

Read more about the MEFV and SAA1 genes.

How do people inherit familial Mediterranean fever?

This condition is inherited in an autosomal recessive pattern, which means both copies of the MEFV gene in each cell have mutations. Most often, the parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition.

In rare cases, familial Mediterranean fever appears to be inherited in an autosomal dominant pattern, which means one copy of an altered MEFV gene is sufficient to cause the disorder. In these cases, an affected person has one parent with the condition.

Where can I find information about treatment for familial Mediterranean fever?

These resources address the management of familial Mediterranean fever and may include treatment providers.

• Gene Review: Familial Mediterranean Fever
• MedlinePlus Encyclopedia: Familial Mediterranean fever

You might also find information on treatment of familial Mediterranean fever in Educational resources and Patient support.

Where can I find additional information about familial Mediterranean fever?

You may find the following resources about familial Mediterranean fever helpful. These materials are written for the general public.

• MedlinePlus - Health information (2 links)
• Additional NIH Resources - National Institutes of Health (2 links)
• Educational resources - Information pages (3 links)
• Patient support - For patients and families (2 links)

You may also be interested in these resources, which are designed for healthcare professionals and researchers.

• Gene Reviews - Clinical summary
• Gene Tests - DNA tests ordered by healthcare professionals
• ClinicalTrials.gov - Linking patients to medical research
• PubMed - Recent literature
• OMIM - Genetic disorder catalog

What other names do people use for familial Mediterranean fever?

• Benign paroxysmal peritonitis
• Familial paroxysmal polyserositis
• FMF
• Hereditary Periodic Fever Syndromes
• Mediterranean Fever, Familial
• MEF
• Periodic Disease
• Periodic peritonitis
• Recurrent polyserositis
• Reimann periodic disease
• Siegal-Cattan-Mamou disease
• Wolff Periodic Disease

See How are genetic conditions and genes named? in the Handbook.

What if I still have specific questions about familial Mediterranean fever?

• See How can I find a genetics professional in my area? in the Handbook.
• Ask the Genetic and Rare Diseases Information Center.
• Submit your question to Ask the Geneticist.

Where can I find general information about genetic conditions?

The Handbook provides basic information about genetics in clear language.

• What does it mean if a disorder seems to run in my family?
• What are the different ways in which a genetic condition can be inherited?
• If a genetic disorder runs in my family, what are the chances that my children will have the condition?
• Why are some genetic conditions more common in particular ethnic groups?

These links provide additional genetics resources that may be useful.

• Genetics and health
• Resources for Patients and Families
• Resources for Health Professionals

What glossary definitions help with understanding familial Mediterranean fever?

amyloidosis ; autosomal ; autosomal dominant ; autosomal recessive ; benign ; cell ; familial ; fever ; gene ; inflammation ; joint ; kidney ; mutation ; population ; protein ; recessive ; sign ; symptom ; syndrome ; white blood cells

You may find definitions for these and many other terms in the Genetics Home Reference Glossary.