Cornelia de Lange syndrome (CDLS) is a multiple congenital anomalies condition firstly described in 1933 by a Dutch pediatrician, Cornelia de Lange.

After the first 30 years in which there was a low report of new cases, the description of new patients increased up to become, in early 80’, a syndrome quite well known also by general pediatricians.

The true incidence of the disease is still uncertain.

Some famous authors (such as J. Opitz) have suggested a figure of 1/10000 live births; more recent evaluations  (M. Ireland) offer different hypotesis (1/15000-1/20000).

It’s possibile to say that the definition of the real incidence of this syndrome is possibly uncorrected both for high number of wrong diagnosis (false positive patients) and an high number of not made diagnosis too (false negative above all in patients with very mild expression).