Child Psychology and Psychiatry

Clinical evaluation of development from birth to five years
Table 6.8
(continued)
Context
Recommended
investigations
Comments
of DiGeorge syndrome, Williams syndrome,
and pseudohypoparathyroidism, and where
motor delay is due to vitamin D deficiency
Second-line tests
The above first-line investigations
PLUS:
Associated abnormal
head size (micro-
or
macrocephaly),
seizures, focal
neurological
features including
severe oromotor
impairment and
speech abnormality
MRI
Where aCGH not available
karyotype and specific
molecular genetic tests,
e.g. looking for 22q
deletion in oromotor and
speech dysfunction
In some cases MRI studies can show a
characteristic signature for metabolic,
neurocutaneous and degenerative disorders
and can even give enough information to
direct subsequent genetic testing
Specific history or
examination findings
suggestive of
neurometabolic
disorders
Metabolic investigations:
serum amino acids,
ammonia, VLCFA,
carnitine, homocysteine,
disialotransferrin
Urine: organic acids,
orotate, GAGs,
oligosaccharides
Key pointers for metabolic disorders in the
clinical history include consanguinity,
failure to thrive and episodic
neurodevelopmental decompensations
(often during minor illnesses). Examination
findings may include coarse facial features
or hepatosplenomegaly
Specific history or
examination findings
suggestive of
epilepsy or specific
behavioural
phenotypes, e.g.
Angelman syndrome
EEG
In Angelman syndrome, characteristic EEG
changes may precede seizures. Diagnosis is
confirmed by deletion or uniparental disomy
on chromosome 15
Specific EEG changes also may help in rare
presentations such as regression in language
and differentiation of seizure-like episodes
such as in Rett syndrome
Regression with or
without associated
features
Referral to a paediatric
neurologist/
consultation for planning
further appropriate
investigations
In many countries human immunodeficiency
virus (HIV) infections are becoming an
important cause of regression with
neurological and neuropsychiatric
manifestations usually presenting in the first
3 years of life
CMV, cytomegalovirus; EEG, electroencephalogram; FISH, fluorescence in situ hybridization; GAG, glycosamino-
glycan; MRI, magnetic resonance imaging; U&E, urea and electrolytes; VLCFA, very long-chain fatty acids.