Background: Down syndrome is a genetic disorder that can cause heart defects and other problems in the body. People with Down syndrome are more likely to have infections, autoimmunity, and blood diseases. Some may need surgery to treat congenital heart problems. During this surgery, doctors sometimes remove part of the thymus. The thymus is an organ that plays a role in immune function. People who have had part of their thymus removed may get sick more often than others do. Objective: This natural history study will gather data about how removing part of the thymus affects the health of people with Down syndrome. Eligibility: People aged 1 year and older with Down syndrome. The study will include both people who have, and those who have not had, surgery to remove part of their thymus. Healthy relatives are also needed. Design: Participants with Down syndrome will have clinic visits at least once a year for 15 years. At each visit they will have a physical exam. They will give blood and stool samples. They will have tests of their heart and lung function. Participants aged 18 years or older may have at least 1 imaging scan: They will lie on a table that slides into a donut-shaped machine. The machine uses X-rays to take pictures of the inside of the body. Participants who have tissue samples collected from their bodies (biopsies) taken during the study may have extra tissue taken for research. Healthy relatives will also have visits once a year for 15 years. They will only have a physical exam and provide blood and stool samples.
Age range
1 Year – 120 Years
Sex
ALL
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The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
Frequency of T21 individuals with laboratory evidence of autoantibodies
Timeframe: Through end of study
Number and type of autoimmune manifestations/year
Timeframe: Through end of study
Frequency of individuals with abnormal T and B cell counts and immunoglobulin serum levels
Timeframe: Through end of study
Proportion of T21 individuals with malignancies by age group (compared to the general population), and type of malignancies
Timeframe: Through end of study
Nature of infections (bacterial, viral, fungal, opportunistic pathogens) requiring hospitalization
Timeframe: Through end of study
Incidence of severe infections requiring hospital admission (number of admissions/year; number of days of hospitalization/year)
Timeframe: Through end of study