High plasma neopterin levels in Chinese children with autism spectrum disorders

Abstract

Background: Neopterin, a pteridine mainly synthesized by activated macrophages, is a marker of inflammation, immune system activation and an active participant in Autism spectrum disorders (ASD). The aim of this study was to assess the clinical significance of plasma neopterin levels in ASD.

Methods: Eighty patients diagnosed with ASD and 80 sex and age matched typically developing children were assessed for plasma levels of neopterin at admission. Plasma neopterin levels were measured using a human ELISA kit and severity of ASD were evaluated with the Childhood Autism Rating Scale (CARS) score.

Results: We found that the mean plasma neopterin level was significantly (P<0.0001) higher in children with ASD as compared to controls. Plasma neopterin increased with increasing severity of ASD as defined by the CARS score. Based on the ROC curve, the optimal cutoff value of plasma neopterin level as an indicator for auxiliary diagnosis of ASD was projected to be 8.5nmol/L, which yielded a sensitivity of 84.2% and a specificity of 80.1%, with the area under the curve at 0.876 (95% CI, 0.825-0.928). Elevated neopterin (≥8.5nmol/L) was an independent diagnosis indicator of ASD with an adjusted OR of 12.11 (95% CI: 5.48-28.11; P<0.0001).

Conclusions: These results indicated that autistic children had higher plasma levels of neopterin, and elevated plasma neopterin levels may be associated with severity of ASD among Chinese children.

Keywords: Autism spectrum disorders; Diagnosis; Immune system; Inflammation; Neopterin.