Autistic children with poor diet face risk of vision loss due to vitamin B12 deficiency

Autistic children with severely limited diets may be at risk for vision loss due to vitamin B12 deficiency, according to new research from The Children's Hospital of Philadelphia. Doctors should consider this deficiency when evaluating and treating children with autism and vision loss, the authors said.

The Children's Hospital study, which appears in the journal Pediatrics, looked at three boys with autism who exhibited behaviors that indicated vision loss, such as groping for items or bumping into walls. Further evaluation and tests revealed optic nerve damage and low levels of B12. The researchers administered a shot of intramuscular vitamin B12 and visual behavior improved modestly in each case after normal levels were reached. All three patients, ages 6, 7 and 13, ate almost no meat or dairy products, important sources of vitamin B12.

"To the best of our knowledge, these are the first three reported cases of vision loss related to a vitamin B12 deficiency related to poor diet in children with autism," said Stacy Pineles, M.D., lead author of the study. She conducted the research as a fellow at Children's Hospital and is now at Ronald Reagan UCLA Medical Center. "Clinicians should have a high index of suspicion for vitamin deficiencies and questions about diet should be part of routine history-taking in this population."

There have been many associations between autism and feeding difficulties, with diet-related deficiencies causing such illnesses as rickets, scurvy and dry eyes. With such patients, the researchers said, parents should also be advised to seek evaluation by a pediatric ophthalmologist or neuro-ophthalmologist who can perform a careful examination to rule out optic nerve damage. 

"Children who refuse foods from animal sources, such as meat and dairy products, are specifically at a higher risk for vitamin B12 deficiency," said Grant T. Liu, M.D., senior author of the study and a neuro-ophthalmologist at Children's Hospital. "In our experience, B12 deficiency optic neuropathy in autism is a recognizable, treatable, and at least partially reversible disorder."

SOURCE The Children's Hospital of Philadelphia