Clinical Features Individuals with Down syndrome have characteristic facies and typical minor anomalies. Most striking in the newborn are the upslanting palpebral fissures, protruding tongue, abnormal palmar creases, and hypotonia. Once the diagnosis is suspected, it should be confirmed by a chromosomal analysis on cultured lymphocytes. The child with trisomy 21 is at risk for other abnormalities and complications. The most common is congenital heart disease, typically a VSD although endocardial cushion defects are also common in Down syndrome.
Cardiac defects require SBE prophylaxis for dental work or other invasive procedures.
An echocardiogram is recommended for all infants with Down syndrome. The presence of Down syndrome per se does not adversely affect the outcome of surgery in the absence of pulmonary hypertension. Hypotonia can lead to poor suck as well as constipation. Genitourinary involvement can include renal malformations, hypospadias, micropenis and undescended testes. Neonatal leukemoid reactions are common.