Down syndrome

Background

Caused by trisomy 21, the most common chromosomal disorder in humans. Patients are at increased risk for injuries and diseases related to issues caused by their genetic condition.

Clinical Features

Patients may have some or all of the following abnormalities. All patients have intellectual disability:

• Mental impairment
• Abnormal teeth
• Stunted growth
• Slanted eyes
• Umbilical hernia
• Shortened hands
• Increased skin back of neck
• Short neck
• Hypotonia tone
• Obstructive sleep apnea
• Ligamentous laxity
• Single transverse palmar crease
• Large tongue
• Congenital heart disease
• Flattened nose
• Strabismus
• Undescended testicles

Pathology by System

The following are common clinical conditions encountered in patients with Down's

Airway

• Macroglossia and a relatively small mouth
• Tracheal stenosis
• Obstructive sleep apnea and pulmonary arterial hypertension

Endocrine

• Hashimoto’s thyroiditis is present in a third of patients and acquired hypothyroidism is common

Gastrointestinal

• Pediatric patients are at risk for intestinal atresia and Hirschsprung’s disease
• Functional illeus and constipation is common

HENT

• Increased incidence of cataracts
• Small ear canals with increased rates of otitis media
• Early onset hearing loss.

Cardiac

• Cardiac defects - endocardial cushion defect atrial and ventricular septal defects, valvular dysfunction

Orthopedic

• Cervical Spine - increased risk of atlanto-axial subluxation
• Ligamentous laxity increases the risk of dislocation or subluxation at any joint