Parents of children with autism take note. It may be possible to predict autism in infants as young as 6 months who have older siblings with the disorder, according to a new study by a national network of researchers.
Infants in such families are at increased risk of developing autism, which is typically diagnosed when a child is 2- to 3-years-old and develops symptoms such as challenges with social skills, repetitive behaviors, delayed speech or nonverbal communication.
Researchers used magnetic resonance imaging — or MRI — to scan the brains of 343 infants when they were 6 months, 12 months and 24 months old. Two-thirds of the infants were high risk, having an older sibling with autism. The scans showed that 70 percent of high-risk toddlers diagnosed with autism at age 2 had an elevated amount of cerebrospinal fluid around their brains at 6 and 12 months, compared to toddlers who were not diagnosed with autism. Cerebrospinal fluid is a clear, colorless liquid that bathes the brain and spine.
This excess fluid “could possibly be an early biological marker for autism,” said Mark Shen, the lead author of the article, published in Biological Psychiatry, and a post-doctoral fellow at the University of North Carolina’s Carolina Institute for Developmental Disabilities. Additional studies are needed to confirm the finding, he said.
Such a marker would allow doctors to identify infants at high risk of developing autism before symptoms are present.
“The earlier we can…