Clinical Manifestations of Down Syndrome
The clinical diagnosis of Down syndrome is not difficult for
experienced physicians due to the characteristic gestalt of
these patients. Patients are usually identified at birth or shortly
thereafter. However, the diagnosis may be challenging in
premature babies, some older patients, certain ethnic groups,
and in mosaicism. Each individual with Down syndrome has
different healthcare needs.
Key diagnostic features are the distinctive physical appear ance, poor growth and developmental delay. The signs and
symptoms may be variable.
Physical Appearance
Individuals with Down syndrome can have the following
physical features-
& Brachycephaly with flat occiput, wide open fontanel
& Flat facial profile*, flat nasal bridge
& Protruding tongue, small mouth
& Dysplastic*, small, low set ears
& Upward slant of palpebral fissures*, epicanthic folds,
squint, speckled iris, palebrae ‘purse’ on laughing or crying
& Short and broad neck, abundant neck skin*
& Short and broad hands, short and broad fingers, small
middle phalanx of 5th finger* (clinodactyly), simian
crease (single palmer crease)
& Increased space between 1 and 2 toes (sandal gap)
& Hypotonia*, hyper-extensibility/hyper-flexibility*, lack
of Moro reflex*
Features marked with asterisks (*) are useful for making a
diagnosis in the newborn. Figure 1 shows the important fea tures of Down syndrome.
Growth
Children with Down syndrome generally have low birth
weight, and poor growth velocity especially during the initial
years, partly contributed by feeding problems due to hypotonia
and a small oral cavity or due to the co-morbid conditions such
as cardiovascular problems and/or other gastrointestinal prob lems. Thereafter, the tendency towards development of obesity
increases with age and is quite common amongst adults with
Down syndrome. The factors responsible for obesity include
associated hypothyroidism, high leptin levels, and poor basal
metabolic rate. Though the Indian growth charts are not avail able, growth monitoring can be done through the currently
available Western Down syndrome growth charts [1]. Regular
growth monitoring in the initial years and then annually
throughout childhood would be helpful in early identification
of under nutrition and obesity in these children  Characteristic facial features in children with Down syndrome at
different ages. Upper panel shows the characteristic flat facies with
upslant of eyes, open mouth appearance and protruded tongue. Bottom
panel shows the short hand and fingers, clinodactyly (solid arrow),
simian crease (arrow head) and sandal gap (dotted arrow)