Familial Mediterranean fever
Febre Familiar do Mediterrâneo
CategoryDefinition
Familial Mediterranean Fever (FMF) manifests as short febrile episodes occurring at variable intervals, with intermittent abdominal, thoracic, joint and/or cutaneous pain, and the possible development of renal amyloidosis. It arises most frequently in subjects originating from the Mediterranean basin. The familial notion is being found less-and-less frequently, because of its recessive inheritance and the tendency towards smaller families. Although it is an autosomal recessive hereditary disease, environmental factors are also important in the triggering of attacks: stress, fatigue, infections. The gene responsible is that encoding marenostrin/pyrin (MEFV; 16p13.3), which is expressed in granulocytes, monocytes and eosinophils. The diagnosis is made by exclusion. Several laboratories in Europe are able to make the genetic diagnosis. A highly effective treatment is available: colchicine (1 to 2 mg/day for life). Its mode of action is unknown but this drug is able to inhibit attacks or prolong intervals between them in 90% of the patients. Interferon-alpha has been prescribed for patients with colchicine-resistant disease.
Diagnostic Criteria
Diagnostic criteria: FMF is the only periodic fever disease where we have established-classification/diagnostic criteria: Livneh et al from Israel have defined diagnostic criteria in adult patients.
According to these criteria there are major and minor criteria as well as supportive criteria. The four major criteria include the typical attacks (≥3 of the same type; rectal temperature 38°C or higher; with duration of 12 – 72 hours) with peritonitis, pleuritis, monoarthritis (hip, knee, ankle) and fever alone. Minor criteria are defined as incomplete attacks, exertional leg pain and favorable response to colchicine.
Recently we have attempted to define criteria for childhood as well. The criteria below reach a good sensitivity and specificity in Turkey.
According to these criteria, the presence of at least 2 of the following criteria are specific for FMF classification: :
- Fever (6-72 hr, ≥3 attacks),
- Abdominal pain (6-72 hr, ≥3 attacks),
- Chest pain (6-72 hr, ≥3 attacks, unilateral),
- Arthritis (6-72 hr, ≥3 attacks, monoarthritis),
- Exertional leg pain and
- Family history of FMF
However neither of these criteria have been validated in FMF patients residing in other countries of in FMF patients of other ethnic groups. (International Society for Autoinflammatory Syndromes)