[Change of plasma level of valine and its relationship with developmental quotient in children with autism].

Objective: To compare the differences of plasma valine level between autistic and healthy children, and to explore the relationship between plasma valine level and developmental quotient in children with autism.

Methods: In this study, a total of 29 autistic children and 30 typically developing children of the same age range were recruited as the autistic group and the control group. The childhood autism rating scale (CARS) was used to assess autistic core symptoms and severity in the autistic children. Children's developmental quotient was evaluated by Gesell developmental schedules (GDS), and plasma valine level was measured by high performance liquid chromatography-tandem mass spectrometry. The correlation between plasma valine level and developmental quotient scores in the autistic group was analyzed.

Results: The plasma level of valine in the autism group was significantly lower than in the control group (P < 0.05). Children in the autism group got significantly lower scores in the adaption, gross motor, fine motor, language function and personal/social function subscales in GDS than in the control group (P < 0.000 1). Plasma valine level in the autism group showed significant positive correlations with scores of the fine motor (r=0.441, P < 0.05) and personal/social function (r=0.437, P < 0.05) subscales in GDS, but showed no significant correlations with scores of the adaption, gross motor and language function subscales in GDS (P>0.05). According to the criteria of CARS, children in the autism group were subdivided into the mild to moderate subgroup and the severe subgroup based on the severity of the autistic symptoms. Compared with children in the mild to moderate subgroup, children in the severe subgroup got significantly lower scores in the adaption, fine motor, language function and personal/social function subscales in GDS (P < 0.05), while there was no significant difference between the two subgroups in gross motor scores and plasma valine level (P>0.05).

Conclusion: The level of valine in plasma of autistic children is relatively lower, and there is a certain relationship between plasma valine level and the fine movement and personal/social function among children with autism.