4.
The Cause of PDDNOS and the Symptons & signs of PDDNOS
The Cause of PDDNOS
Both behavioral and biological studies have
generated sufficient evidence to suggest that PDDNOS is
caused by a neurological abnormality--problems with the
nervous system. However, no specific cause or causes have
been identified.
While
studies have found various nervous-system problems, no single
problem has been consistently found, and exact causes are
far from clear. This may be due to the current approach
of defining PDDNOS based on behaviors (as opposed to, say,
genetic testing). Hence, it is possible that PDDNOS is the
result of several different conditions. If this is the case,
it is anticipated that future studies will identify a range
of causes.
The
Symptons and Signs of PDDNOS
Generally,
children are 3 to 4 years old before they exhibit enough
symptoms for parents to seek a diagnosis. There is no set
pattern of symptoms and signs in children with PDDNOS. It
is important to realize that a very wide range of diversity
is seen in children with PDDNOS. All the items of behavior
described in this section are common in these children,
but a single child seldom shows all the features at one
time. In other words, all children with PDDNOS do not have
the same degree or intensity of the disorder. PDDNOS can
be mild, with the child exhibiting a few symptoms while
in the school or neighborhood environment. Other children
may have a more severe form of PDDNOS and have difficulties
in all areas of their lives. Because of the possibility
that PDDNOS and Autistic Disorder are on a continuum, many
clinical features described in the following
section are very similar to those being described in
the literature for Autistic Disorder.
