Autosomal recessive disorder.
Associated with recurrent episodes of peritonitis, pleuritis, arthritis and fever which are brief in duration.
Occurs in families with Mediterranean origin more commonly than other ethnic groups.
Largely encountered in patients from Armenia, Turkey, Arabic countries and with Sephardic Jewish background.
Caused by mutations in the MEFV (Mediterranean fever) gene.
Widespread tissue involvement makes it indistinguishable from reactive systemic amyloidosis.
MEFV gene produces protein pyrin, associated with fever, or marenostrin.
Protein abnormality expressed mainly in neutrophils and may inhibit C5a or IL-8.
Patients lack the ability to deactivate target chemotactic factor (C5a) produced by inflammation resulting in episodes of fever, inflammation in peritoneum, pleura and joints.
Repeated episodes on inflammation result in excess production of amyloid A protein with deposition of the protein in kidneys.
Only patients with specific MEFV haplotypes develop amyloidosis.
Typically diagnosed during childhood.
90% of diagnosed patients are younger than 20 years of age.
Events occur without warning and lasts 2-3 days, with peak intensity of symptoms within the e first 12-24 hours.
Typically have sudden onset of fever, abdominal pain, chest pain, arthritis, constipation followed by diarrhea and rash, particularly on the lower extremities.
May be associated with myalgias, pelvic inflammatory disease, scrotal inflammation, and vasculitis.
Attacks occur spontaneously.
Attacks may be brought on by exercise or stress.
Patients may be attack free for weeks to months.
Colchicine usually controls the disease process.