Some Complications of Down Syndrome*

System

Deficit

Cardiac

Congenital heart disease, most often ventricular septal defect and atrioventricular canal defect

Increased risk of mitral valve prolapse and aortic regurgitation (more frequently seen in adults)

Central nervous system

Cognitive impairment (mild to severe)

Motor and language delay

Autistic behavior

Early-onset Alzheimer disease

Gastrointestinal

Duodenal atresia or duodenal stenosis

Hirschsprung disease

Celiac disease

Endocrine

Hypothyroidism

Diabetes

Eyes, ears, nose, and throat

Ophthalmic disorders (eg, congenital cataracts, glaucoma, strabismus, refractive errors)

Hearing loss

Increased incidence of otitis media

Growth

Short stature

Obesity

Hematologic

Thrombocytopenia

Neonatal polycythemia

Transient myelodysplastic disorder

Acute megakaryoblastic leukemia

Acute lymphocytic leukemia

Musculoskeletal

Atlantoaxial and atlanto-occipital instability

Joint laxity

Respiratory

Obstructive sleep apnea

* Not all complications are present in a given patient, but incidence is increased compared with unaffected population.