Immune dysfunction and malignancy in people with Down syndrome

People with Down syndrome have an increased risk of some autoimmune conditions (eg thyroid dysfunction, coeliac disease, type 1 diabetes, alopecia areata), and immune dysfunction leading to infections (particularly respiratory and skin infection).

Leukaemia is more common in children and young adults with Down syndrome; it is rare in older adults, but is still more common than in the general population. Presentation of leukaemia may be subtle and nonspecific (eg fever, fatigue, weakness, weight loss, nose or gum bleeding). More specific symptoms and signs include frequent infections, bruising, petechiae, bone pain, lymphadenopathy and splenomegaly.

Transient myelodysplasia and macrocytosis are also more common in people with Down syndrome.

People with Down syndrome have a lower risk of solid tumours than the general population.