Familial Mediterranean Fever
An inherited cause of recurring fever and painful inflammation
Quick Facts
- Type: Inherited autoinflammatory disorder
- Cause: Changes in the MEFV gene
- Hallmark: Recurring fevers with abdomen, chest, or joint pain
- Key treatment: Colchicine to prevent attacks
Overview
Familial Mediterranean fever (FMF) is an inherited autoinflammatory disorder, meaning the body's innate immune system becomes overactive and triggers bouts of inflammation without an infection. It causes recurring episodes of fever along with pain in the abdomen, chest, or joints. Episodes typically last a few days and then resolve, with symptom-free periods in between.
FMF most often affects people of Mediterranean and Middle Eastern ancestry, including those of Armenian, Arab, Turkish, and Sephardic Jewish descent, though it can occur in others. It is caused by changes in a gene called MEFV. With the right treatment, attacks can usually be prevented and the long-term risks reduced.
One of the main reasons to treat FMF, even between attacks, is to prevent a serious long-term complication called amyloidosis, in which a protein gradually builds up in organs such as the kidneys and can damage them. Taking preventive medication consistently lowers this risk. Because the abdominal pain of an attack can be severe and mimic a surgical emergency, an accurate diagnosis also helps people and their doctors avoid unnecessary operations.
Symptoms
Attacks usually begin in childhood or young adulthood and come and go. A typical episode may include:
- Sudden fever
- Abdominal pain, sometimes severe enough to mimic appendicitis, from inflammation of the lining of the abdomen
- Chest pain from inflammation of the lining around the lungs
- Painful, swollen joints, often in the legs
- A red, tender rash on the lower legs in some people
- Muscle aches
Attacks generally last one to three days and resolve on their own, with the person feeling well between episodes.
Causes
FMF is caused by changes (variants) in the MEFV gene, which provides instructions for a protein that helps control inflammation. When this gene is altered, the immune system can switch on inflammation inappropriately, producing the recurring attacks.
It is usually inherited in a pattern in which a person has two altered copies of the gene, one from each parent. Carrying a single altered copy may cause milder or no symptoms in many people. Genetic testing can help confirm the diagnosis in many cases.
Risk Factors
- Mediterranean or Middle Eastern ancestry, such as Armenian, Arab, Turkish, or Sephardic Jewish heritage
- A family history of FMF
- Inheriting altered MEFV gene copies from both parents
- Symptoms often beginning in childhood
Diagnosis
Diagnosis is based on the pattern of recurring attacks, ancestry, and family history, supported by tests:
- Medical and family history: Recurrent short episodes of fever with abdominal, chest, or joint pain.
- Blood tests: Show signs of inflammation during attacks.
- Genetic testing: Looks for changes in the MEFV gene to support the diagnosis.
- Response to treatment: Improvement with colchicine can help confirm FMF.
Because abdominal attacks can mimic surgical emergencies, the diagnosis also helps avoid unnecessary operations.
Treatment
Treatment aims to prevent attacks and protect against long-term complications:
- Colchicine: The main treatment, taken regularly to reduce the frequency and severity of attacks and to help prevent a serious complication called amyloidosis.
- Other medicines: For people who do not respond to or cannot tolerate colchicine, additional medicines that target inflammation may be used.
- Symptom relief: Pain relief and supportive care during attacks.
Taking colchicine consistently, even when feeling well, is important because it works mainly by preventing attacks rather than treating one in progress.
Prevention
Attacks and complications can be reduced by:
- Taking colchicine regularly as prescribed, even between attacks
- Attending follow-up visits and monitoring for kidney effects
- Genetic counseling for families with a history of FMF
- Reporting new or worsening symptoms to your doctor
The most important long-term goal is preventing amyloidosis, a buildup of protein that can damage the kidneys.
When to See a Doctor
See a doctor if you have recurring episodes of fever with abdominal, chest, or joint pain, especially with a relevant family background. Seek urgent care if you have:
- Severe abdominal pain that is new, persistent, or different from your usual attacks
- High fever with severe illness
- Signs of kidney problems such as swelling or foamy urine
Severe abdominal pain should always be checked to rule out other emergencies such as appendicitis.
Frequently Asked Questions
What is familial Mediterranean fever?
It is an inherited autoinflammatory disorder that causes recurring episodes of fever and painful inflammation in the abdomen, chest, or joints. Episodes usually last a few days, with symptom-free periods in between, and are caused by changes in a gene called MEFV.
Who gets familial Mediterranean fever?
It most often affects people of Mediterranean and Middle Eastern ancestry, including those of Armenian, Arab, Turkish, and Sephardic Jewish descent, though it can occur in others. Symptoms usually begin in childhood or young adulthood and there is often a family history.
How is familial Mediterranean fever treated?
The main treatment is colchicine, taken regularly to reduce the frequency and severity of attacks and to prevent a serious complication called amyloidosis. People who do not respond to colchicine may be offered other medicines that target inflammation.
Why is colchicine taken even between attacks?
Colchicine works mainly by preventing attacks rather than stopping one already in progress, so it must be taken consistently. Regular use also helps protect the kidneys from amyloidosis, the most important long-term complication of the condition.
Can the abdominal pain be confused with appendicitis?
Yes. FMF attacks can cause severe abdominal pain from inflammation of the abdominal lining, which can closely resemble appendicitis. Knowing the diagnosis helps avoid unnecessary surgery, but any new or unusually severe abdominal pain should still be evaluated to rule out other emergencies.
References
- Mayo Clinic. Familial Mediterranean fever — Symptoms and causes.
- National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS). Familial Mediterranean Fever.
- MedlinePlus, U.S. National Library of Medicine. Familial Mediterranean fever.
- Genetic and Rare Diseases Information Center (GARD). Familial Mediterranean fever.