Rare diseases in the elderly: a new perspective for the specialist in geriatrics

Rare diseases (RD) encompass a broad spectrum of highly heterogeneous illnesses characterized by a prevalence lower than 1:2000 in general population. Although relatively uncommon, when considered as a whole, these pathologies represent a relevant public health problem. In light of their usual early onset and high severity and mortality, RD have been traditionally regarded as affecting mainly childhood or young adulthood, and considered to be excluded from filed of interest of geriatric specialists. However, more recent epidemiological studies, suggest that demographic changes, sometimes joined with advances in diagnostic and therapeutic strategies, are permitting longer survival of some persons affected by these conditions, thus making RD compatible with geriatric age. Hence, in the next future, specialists in geriatrics will be referred to by an increasing number of elderly subjects with RD seeking medical care. Geriatricians should be aware about the high management complexity of elderly patients with RD, characterized by considerable frailty status, related to both the primary RD and to the ageingrelated condition.