What is Costello syndrome?
Costello syndrome is a disorder that affects many parts of the body. This condition is characterized by delayed development and intellectual disability, distinctive facial features, loose folds of extra skin (especially on the hands and feet), and unusually flexible joints. Heart abnormalities are common, including an unusually fast heartbeat (tachycardia), structural heart defects, and a form of heart disease that enlarges and weakens the heart muscle (hypertrophic cardiomyopathy). Although infants with Costello syndrome may be larger than average at birth, they have difficulty feeding and grow more slowly than other children. People with this condition have relatively short stature and may have reduced growth hormone levels. Beginning in early childhood, people with Costello syndrome are at an increased risk of developing certain cancerous and noncancerous tumors. The most common noncancerous tumors seen with this condition are papillomas, which are small, wart-like growths that usua
