Merck Manual

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Some Complications of Down Syndrome

Some Complications of Down Syndrome

Body System

Complication*

Blood

Acute lymphocytic leukemia (ALL) or acute myeloid leukemia (AML)

Low platelet count (thrombocytopenia)

High red blood cell count in the newborn (polycythemia in the newborn)

Brain

Intellectual disability (mild to severe)

Delayed speech and motor skills

Digestive tract

Malformed intestines

Endocrine system

Eyes and ears

Cataracts, glaucoma, crossed eyes (strabismus)

Growth

Heart

Muscles and bones

Unstable connections between the first 2 bones in the neck

Loose joints

* Not all complications are present in each person.