Pitt-Hopkins syndrome is now most frequently referred to as PTHS. It is formed by taking the first and last letters of Pitt and the first letter of Hopkins , who were the two doctors who characterised the syndrome in 1978, together with the S for syndrome. This is to distinguish it from another rare syndrome known as Pallister-Hall syndrome which was already known as PHS in the science and medical literature. It is still referred to as PHS in some medical literature.
