Life threatening conditions diagnosed in newborn with Down syndrome include:

Congenital heart disease :

Congenital heart disease represents the most common cause of death in childhood. The cardiac defects that can occur are:

• Endocardial cushion defect
  
  
• Ventricular septal defect
  
  
• Patent ductus arteriosus
  
  
• Atrial septal defect
  
  
• Tetralogy of Fallot
  
  

Diagnosis of cardiac disease in infants with Down syndrome is not always obvious; in fact, clinical examination in the newborn period may be entirely normal. The alerting signs are poor feeding, easy fatigability, dyspnea, diaphoresis, cyanosis, and a cardiac murmur. However, some infants are asymptomatic if they are not experiencing congestive cardiac failure. Therefore, any infant with Down syndrome needs careful evaluation by current techniques such as echocardiography, Doppler flow analysis, etc.

Congenital gastrointestinal disease :

Duodenal obstruction occurs more frequently in infants with Down syndrome. The infant may present with bile stained vomiting, abdominal distension and a visible peristaltic wave. A "double bubble sign" characterizes the abdominal radiograph. The obstruction may be caused by congenital atresia, intrinsic stenosis, or extrinsic stenosis secondary to annular pancreas or malrotation of the bowel with bands. In the neonatal period, these lesions may constitute surgical emergencies.

Other malformations that can occur are:

• Hirschsprung disease
  
  
• Esophageal atresia
  
  
• Pyloric stenosis
  
  
• Diverticulum of the stomach
  
  
• Malrotation of the bowel
  
  

Hematological disease :

The incidence of leukemia is higher in infants with Down syndrome. Other disorders described in newborns include:

• Polycythemia
  
  
• Thrombocytopenia
  
  
• Erythroblastosis fetalis
  
  

Ophthalmologic problems :

Nystagmus and stabismus occur frequently in the newborn period and require consultation to rule out corneal opacities. Other ocular problems seen are:

• Refractive error
  
  
• Blepharoconjunctivitis
  
  
• Cataracts
  
  
• Keratoconus
  
  
• Retinal pathology
  
  
• Optic nerve hypoplasia
  
  

An abnormality detected on physical examination or poor visual tracking requires further investigation.

Urogenital abnormalities :

These include:

• Micropenis
• Cryptorchidism
• Hypospadius
• Anomalies of the kidneys and ureters

Endocrine abnormalities :

Persistent primary congenital hypothyroidism commonly occurs in newborns with Down syndrome. Thus, thyroid screening which is so important for all infants, is particularly relevant for infants with Down syndrome.

Ear problems :

There is an increased incidence of congenital sensorineural hearing loss in children with Down syndrome, so a hearing screen is recommended before discharge. Middle ear effusions may also be present.