[Genetic diagnosis of periodic disease]

Periodic disease is a hereditary disorder. Until recently its diagnosis was essentially based on clinical criteria. When the clinical picture was incomplete or atypical, it often required elimination of other diagnoses which sometimes involved extensive and useless investigations. Diagnosis was consequently delayed or irrelevant, with the risk of renal failure when the patient was not treated (or tardily treated).

Efforts of molecular geneticists have allowed to track and recently to identify the gene (MEFV) responsible for this disease. Today blood sampling enables identification of the causative mutations, sometimes even before the onset of symptoms.

Four mutations clustered on exon 10 already account for 74% of cases in patients originating from the most affected populations and presenting with complete clinical picture. Identification of rare mutations should progressively allow improvement of the test sensitivity, especially in patients with a less typical form of the disease.