Down syndrome in Management

DEFINITION
Down syndrome is a disorder characterized by mental retardation and multiple organ defects. It is caused by a chromosomal abnormality (trisomy 21).

PHYSICAL FINDINGS AND CLINICAL PRESENTATION
● Microcephaly
● Flattening of occiput and face
● Upward slant to eyes with epicanthal folds
● Brushfi eld spots in iris
● Broad stocky neck
● Small feet, hands, digits
● Single palmar crease
● Hypotonia
● Short stature
● Associated with congenital heart disease, malformations of the GI tract, cataracts, hypothyroidism, hip dysplasia
● About half of children with Down syndrome are born with congenital heart disease, with the most common lesions being atrial septal defect and ventricular septal defect

● Persistent primary congenital hypothyroidism is found in 1 in 141 newborns with Down syndrome, as compared with 1 in 4000 in the general population.
● Ophthalmologic disorders increase in frequency with age. Over 80% of children aged 5 to 12 years have disorders that need monitoring or intervention, such as refractive errors, strabismus, or cataracts.
CAUSE
● Nondisjunction of chromosome 21
DIAGNOSIS
● Prenatal cytogenic diagnosis by amniocentesis or chorionic villus sampling
● Combined use of serum screening and fetal ultrasound testing for thickened nuchal fold has 80% detection rate, with 5% false-positives
● Postnatal chromosomal karyotype.

DIFFERENTIAL DIAGNOSIS
● Congenital hypothyroidism
● Other chromosomal abnormalities
WORKUP
● Postnatal karyotype
● Thyroid screening at birth, at age 6 months, and yearly thereafter
● Echocardiography, usually performed in neonatal period
TREATMENT
● Treatment consists of vigilant monitoring for comorbid states, such as obesity, hypothyroidism, leukemia, hearing
loss, and valvular heart disease.
● Thyroid screening at birth, at age 6 months, and yearly thereafter
● Prevention of obesity with low-calorie, high-fi ber diet
● Monitoring for hematologic problems
● Auditory brainstem responses in all newborns and aggressive testing for hearing loss in children with chronic otitis
media
● Echocardiography in all newborns and cardiac assessment of adolescents for development of mitral valve prolapse
● Ophthalmologic assessment by age 6 months for congenital cataracts and annual examinations for monitoring of refractive errors and strabismus
● Regular dental care
● Pelvic examination of women who are sexually active or who have menstrual problems
● Dermatologic issues such as folliculitis can become problematic in adolescents and require careful attention to hygiene and topical antibiotics