Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impaired social communication and repetitive behaviors. Studies have indicated that immune system dysregulation and chronic neuroinflammation play a significant role in the development of the disorder. This study aimed to investigate the potential use of inflammatory cytokines, such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), as biomarkers for predicting the diagnosis of ASD. The current study included 88 children, 50 of whom had ASD and 38 who were typically developing and healthy, all aged 3-13 years. Serum levels of IL-6 and TNF-α were measured in both groups, and statistical analyses were performed to assess differences and correlations between the two groups. Diagnostic accuracy was assessed using the ROC curve. Children with ASD showed higher levels of IL-6. (194.21 ± 81.89 pg/mL) and TNF-α (360.74 ± 134.54 pg/mL) compared with controls (75.60 ± 23.56 pg/mL and 103.80 ± 50.57 pg/mL; p ≤ 0.05). A moderate positive correlation existed between IL-6 and TNF-α (r = 0.395, p ≤ 0.01), and gestational age correlated strongly with birth weight (r = 0.568, p ≤ 0.001). ROC curve analysis showed high performance: Interleukin-6 exhibited 90% sensitivity and 98% specificity at a concentration of 123.80 pg/ml, while tumor necrosis factor-alpha (TNF-α) showed 90% sensitivity and 100% specificity at a concentration of 228.92 pg/ml (p ≤ 0.001). These results indicate a strong association between elevated levels of both interleukin-6 and TNF-α and autism spectrum disorder, supporting the role of inflammatory pathways and highlighting their potential use in the early detection and appropriate treatment of autism spectrum disorder.
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