Familial Mediterranean fever (FMF), also known as Armenian disease, is a hereditary inflammatory disorder. FMF is an autoinflammatory disease caused by mutations in MEFV, a gene which encodes a 781?amino acid protein denoted pyrin. The disorder has been given various names including familial paroxysmal polyserositis, periodic peritonitis, recurrent polyserositis, benign paroxysmal peritonitis, periodic disease or periodic fever, Reimann periodic disease or Reimann's syndrome, Siegal-Cattan-Mamou disease, and Wolff periodic disease.
Symptoms: Abdominal attacks, featuring abdominal pain, acute abdominal pain like appendicitis. Chest attacks include pleuritis (inflammation of the pleura) and pericarditis. Scrotal attacks due to inflammation of the tunica vaginalis occurs in up to 5% and may be mistaken for acute scrotum.
Diagnosis: An acute phase response is present during attacks, with high C-reactive protein levels, an elevated white blood cell count and other markers of inflammation. In patients with a long history of attacks, monitoring the kidney function is of importance in predicting chronic kidney failure. A genetic test is also available to detect mutations in the MEFV gene.
Treament: Attacks are self-limiting, and require analgesia and NSAIDs (such as diclofenac) Colchicine, a drug otherwise mainly used in gout, decreases attack frequency in FMF patients. Approximately 5?10% of FMF cases are resistant to colchicine therapy alone.
Epidemology: Traditionally, Italians have been considered little affected by FMF, despite the geographical position of Italy (northern Mediterranean basin) and the migratory changes in its population. Italian FMF patients, 40 women and 31 men, aged from 3 to 75 years, have shown all the clinical manifestations indicative of FMF described in the literature, but with a lower incidence of amyloidosis. The genetic tests have been contributive in 42% of cases.