Saturday, November 22, 2014
Head Circumference and Autism
We were recently referred a child from China for adoption. However, her head circumference measurements concern me. Her head circumference from birth through 8 months was the 33cm, 33, 35, 35.6, 36, 38, 41.5, 42.1, 42.8. Her height measurements for birth through 8 months was 52 cm, 53, 58, 62.5, 62, 63, 65.5, 67.5, 68.7. Her weight measurements were 3.5kg, 3.8, 4.8, 5.1, 6.3, 6.7, 7.4, 7.6, 7.9. Now at 15 months she is significantly delayed. She does not stand or speak any words yet and when they call her name there is a delay before she responds to them. I recently read that rapid head growth in the first 12 months can be a strong indicator of autism. I know there is no way to be sure, but based on the limited information above, is the likelihood greater that she does have autism or is possibly mildly mentally retarded or that she isn`t. The only other info I have is that the other children in the orphanage are not delayed, they are developmentally on target for speech and standing/walking. So this delay can not be attributed to typical institutional delay.
This question raises several interesting issues.
One is the distinction between signs/symptoms and incidental findings. The concerning features of the case mentioned are the developmental delay and unresponsiveness more so than the head size. Even in the presence of normal head size, such symptoms should elicit a thorough pediatric/neurological/psychiatric evaluation. There are various possible explanations for unresponsiveness and late talking, standing, etc., including:
- mental retardation
- esoteric neurological diseases
- as well as autism.
Although some children with autism have been reported to have larger-than-normal heads, some with autism have normal head size.
On the other hand, a large head with no signs/symptoms of impairment in any domain might be an incidental "broad normal variation" given the wide variation in sizes of various body parts among normal children. However, a large head in the presence of developmental or neurological signs/symptoms raises a question about possible hydrocephalus, which should be evaluated.
And, of course, a large head could be an incidental finding in a child with autism, but this cannot be concluded until other explanations are ruled out, some of which are treatable.
L Eugene Arnold, MD, MEd
Professor Emeritus of Psychiatry
College of Medicine
The Ohio State University