RESUMEN
Early detection of cognitive developmental delay (CDD) and autism spectrum disorder (ASD) is challenging, despite the numerous scientific studies conducted and different therapeutic strategies. Lack of a biomarker for autism is a limiting factor for early diagnosis, which could provide better outcome with early start of therapy. Because of the high serum fetuin-A concentration during intrauterine life, it has been suggested that fetuin-A may have a role in brain development. The current study sought to determine if fetuin-A, a multifunctional glycoprotein thought to have a role in brain development, may be used as a biomarker for the diagnosis of ASD and developmental delay. The study involved 55 children with cognitive developmental delays and 40 healthy children. Two categories of children with cognitive developmental delays were identified. The participants were subjected to a psychiatric assessment as well as developmental testing. Only 54.5% of the 55 individuals had CDD, whereas 45.5% had ASD. Using an ELISA kit, the levels of serum fetuin-A were determined spectrophotometrically. The serum fetuin-A levels in the patients from the test group were found to be significantly lower than in the healthy individuals (p < 0.001). The cutoff value for the serum fetuin-A levels for cognitive developmental delay and autism spectrum disorder was 518 µg/liter, according to the results of ROC analysis (84.6% sensitivity and 91.4% specificity, AUC: 0.95, p < 0.001). The findings suggest that the serum fetuin-A level may be used to diagnose autism spectrum disorder and cognitive developmental delays.