Clinical Pearls & Morning Reports
A third copy of chromosome 21, trisomy 21, has long been recognized as the cause of Down syndrome (DS). Many medical conditions are more common in persons with DS than in the general population and affect health, development, and function. Some of these conditions require immediate intervention at birth, and others warrant lifelong surveillance. Read the NEJM Review Article here.
Q: Has life expectancy increased among persons with DS?
A: Improved management of congenital heart disease has contributed to an increase in life expectancy for patients with DS, from 30 years in 1973 to 60 years by 2002. Pulmonary-artery hypertension, with or without congenital heart disease, occurs in 1.2 to 5.2% of persons with DS. Surveillance for pulmonary-artery hypertension throughout childhood is indicated, since this disorder is associated with other conditions that are common in patients with DS, including obstructive airway disease (obstructive sleep apnea), gastroesophageal reflux, and obesity, which require assessment and intervention to prevent complications.
Q: Are respiratory disorders particularly hazardous for persons with DS?
A: Airway management in patients with DS is a challenge because of airways that are small for the patient’s age, micrognathia, relative macroglossia, tracheal stenosis caused by complete tracheal rings, hypotonia, and obstructive airway disease. As a result, respiratory disorders are common causes of illness and death in affected children and adults.
A: Hematologic abnormalities are common in patients with DS. Transient abnormal myelopoiesis, a form of myeloid preleukemia, occurs in up to 10% of neonates with DS. The disorder, which occurs predominantly in newborns and almost always before the age of 5 years, usually resolves spontaneously, but early detection and monitoring by pediatric hematologic specialists are recommended, since the risk of leukemia among patients with transient abnormal myelopoiesis is 20 to 30%. Leukemia independent of transient abnormal myelopoiesis develops in 2 to 3% of all patients with DS, particularly acute myeloid leukemia. Epidemiologic studies suggest that DS may provide overall protection against the development of solid tumors. However, testicular cancer occurs more frequently in persons with DS than in age-matched populations.
A: Autoimmune conditions, including Hashimoto’s disease, type 1 diabetes, alopecia, celiac disease, juvenile idiopathic arthritis, and vitiligo, occur in disproportionate numbers among persons with DS as compared with age-matched cohorts. Early recognition and treatment of such conditions may minimize complications across the life span. Persons with DS should be tested for thyroid disorders at birth, in early infancy, annually throughout life, and whenever any suggestive symptoms, such as dry skin, constipation, change in growth trajectory, and unexplained weight gain, occur. The incidence of thyroid abnormalities, including persistent hypothyroidism and Hashimoto’s disease, among persons with DS is approximately 50% by 45 years of age.