Autism Diagnosis Possible via 'Sniff Test', According to Study

A new study reveals that a test to see the olfactory response of children with autism spectrum disorder (ASD) could be used to diagnose the behavioral disorder.

Researchers from Israel found that children with ASD react differently to smells. Most normal children respond positively to pleasant smells by sniffing it longer, but limit their breathing when encountering rancid odors. The findings were published Thursday in the journal Current Biology.

In a press release published in Science Daily, co-author Noam Sobel from Israel's Weizmann Institute of Science said that there was a significant difference in the sniffing pattern between ASD children and their normally-developing counterparts.

"We can identify autism and its severity with meaningful accuracy within less than 10 minutes using a test that is completely non-verbal and entails no task to follow," Sobel stated in the release.

"This raises the hope that these findings could form the base for development of a diagnostic tool that can be applied very early on, such as in toddlers only a few months old. Such early diagnosis would allow for more effective intervention."

In the study, researchers gathered 18 children with ASD and 18 children without ASD. They presented both groups with pleasant and unpleasant smells and took notes on how they responded to the odors. During the course of changing the smells from pleasant to unpleasant, researchers found that ASD children did not respond, while the control group did, notes Science World Report.

"It's a semi-automated response," said Liron Rosenkrantz, a neuroscientist at the institute and co-author of the study, via The New York Times. "It does not require the subject's attention."

The sniff test had 81 percent success rate of correctly identifying which children have ASD and those who did not have it. The results also noted that the longer the sniff response took, the more severe their behavioral disorder was.

The scientists plan to further research whether the sniff-response test could be used to identify other neurodevelopment disorders.

Dr. Paul Wang, senior vice president and head of medical research for autism organization Autism Speaks, said via CNN that it may be "too early to say" if the sniff-test could be used to diagnose autism.

However, Dr. Wang adds that the study is helpful for autism research with regards to sensory behaviors. "I think this really fits well with increasing research on general sensory symptoms in autism," he said.