Top 10 rarest diseases you've never heard of

One of then inspired the film The Curious Case of Benjamin Button

Updated: 

There are some mystery diseases you may never have heard of. From Foreign Accent Syndrome, to the Tree Man Illness, to Hutchinson-Gilford Progeria Syndrome – which inspired "The Curious Case of Benjamin Button" – these are some of the strangest known medical conditions.

See also: Five weird signs that you're dehydrated

See also: Why sleeping naked is good for your health