Definition

Familial Mediterranean fever (FMF) is a rare disorder passed down through families (inherited). It involves repeated fevers and inflammation that often affects the lining of the abdomen, chest, or joints.

Alternative Names

Familial paroxysmal polyserositis; Periodic peritonitis; Recurrent polyserositis; Benign paroxysmal peritonitis; Periodic disease; Periodic fever; FMF

Causes

FMF is most often caused by a mutation in a gene named MEFV. This gene creates a protein involved in controlling inflammation. The disease appears only in people who received two copies of the altered gene, one from each parent. This is called autosomal recessive inheritance or an autosomal recessive condition.

FMF most often affects people of Mediterranean ancestry. These include non-Ashkenazi (Sephardic) Jews, Armenians, and Arabs. People from other ethnic groups can also be affected.

Symptoms

Symptoms usually begin between ages 5 and 15. Inflammation in the lining of the abdominal cavity, chest cavity, skin, or joints occurs along with high fevers that usually peak in 12 to 24 hours. Attacks may vary in severity of symptoms. People are usually symptom-free between attacks.

Symptoms may include repeated episodes of:

• Abdominal pain
• Chest pain that is sharp and gets worse when taking a breath
• Fever or alternating chills and fever
• Joint pain
• Skin sores (lesions) that are red and swollen and range from 5 to 20 cm in diameter

Exams and Tests

If genetic testing shows that you have the MEFV gene mutation and your symptoms match the typical pattern, the diagnosis is nearly certain. Laboratory tests and x-rays or other imaging tests are used to rule out other possible diseases to help confirm the diagnosis.

Levels of certain blood tests may be higher than normal when done during an attack. Tests may include:

• Complete blood count (CBC) that includes white blood cell count
• C-reactive protein (CRP) to check for inflammation
• Erythrocyte sedimentation rate (ESR) to check for inflammation
• Fibrinogen test to check blood clotting

Treatment

The goal of treatment for FMF is to control symptoms. Colchicine, a medicine that reduces inflammation, may help during an attack and may prevent further attacks. It can also help prevent a serious complication called systemic amyloidosis, which is common in people with FMF.

NSAIDs may be used to treat fever and pain.

Outlook (Prognosis)

There is no known cure for FMF. Most people continue to have attacks, but the number and severity of attacks is different from person to person.

Possible Complications

Amyloidosis may lead to kidney damage or not being able to absorb nutrients from food (malabsorption). Fertility problems in women and men and arthritis are also complications.

When to Contact a Medical Professional

Contact your provider if you or your child develops symptoms of this condition.

References

Verbsky JW. Hereditary periodic fever syndromes and other systemic autoinflammatory diseases. In: Kliegman RM, St. Geme JW, Blum NJ, Shah SS, Tasker RC, Wilson KM, eds. Nelson Textbook of Pediatrics. 21st ed. Philadelphia, PA: Elsevier; 2020:chap 188.

Shohat M. Familial Mediterranean fever. In: Adam MP, Ardinger HH, Pagon RA, Wallace SE, Bean LJH, Stephens K, Amemiya A, eds. GeneReviews [Internet]. University of Washington, Seattle, WA: 2000 Aug 8 [updated 2016 Dec 15]. PMID: 20301405 pubmed.ncbi.nlm.nih.gov/20301405/.