The Numbers of Behçet: A Rare Disease?

Abstract

A disease is considered rare when it has a low prevalence [<5 affected individuals in 10,000]. Currently, approximately 30 million of Europeans have a rare disease on an estimated total number of rare conditions of about 6,000 to 8,000. Numbers of Behçet disease (BD) reveals significant regional differences. The highest prevalence rates are recorded in the Mediterranean and Middle/Far Eastern regions (e.g. in Turkey it affects 400:10,000 individuals): in these areas BD cannot be regarded as a rare disease. In other European countries prevalence rates are lower ranging from 0.3 to 6.4 per 100,000 persons: these figures allow BD to be brought within the definition of a rare condition. Albeit rare diseases are heterogeneous they share some similar features including a genetic cause/predisposition, an onset in the paediatric age, a multisystem involvement, a chronic/disabling course and high psychological, social and economic burdens. Despite therapeutic agents are many, definite treatments do not yet exist. Due to such complexity, multidisciplinary approaches are needed to optimise management, follow-up and treatments. Improving the access of patients to experts care reduces the rate of delayed diagnosis/misdiagnosis and the use of unnecessary/harmful therapies. Networks of centres of expertise have been proposed [e.g. the European Reference Network on Rare Diseases, RD ERNs]. National EU help lines on rare diseases are currently working to provide a service of information and support: notably, during the last 5 years, BD was recorded among the six most frequent diseases enquired (out of 15,807 in 16,000 phone calls) at the Italian Helpline “Telefono Verde Malattie Rare” of the National Institute of Health.