26285
Estimation and Comparison of Serum and Salivary Immunoglobulin G4 Levels in Children with Autism Spectrum Disorders: A Case Control Study from South India
Objectives: To estimate and compare the serum and salivary immunoglobulin G4 (IgG4) levels in children with autism and typically developing control children (TD) from South India.
Methods: Case-control study. Children of special schools and those visiting hospitals in Mangaluru and neighbouring districts of Karnataka and Kerala were recruited. We collected blood and saliva from children with ASD (n=55), and age-matched typically developing (TD) controls (n=60). Childhood Autism Rating Scale (CARS) used to identify ASD children. Samples were assayed in duplicate using the commercial enzyme-linked immunosorbent assay (ELISA) kit (Human IgG4 Ready-Set-Go Kit, eBioscience, San Diego, CA, USA; #88-50590).
Results: The mean ages of autistic children were 10.7 year (SD± 4.2) and healthy children 11.2 year (SD± 2.7). The CARS assessment of children with ASD showed that 60% were under severe autism while 40% of the cases were mild to moderate autism. Routine laboratory tests showed no significant difference among two groups. Children with ASD had significantly higher levels of serum and salivary IgG4 (44.80 ±20.76 and 0.89 ±0.69 mg/dL) as compared to the TD (34.90 ± 20.19; p=0.021 and 0.56 ± 0.38 mg/dL; p= 0.024). Both serum and salivary IgG4 levels were positively correlated in ASD (R= 0.3729: p= 0.005), TD (R= 0.4644; p=0.0003).
Conclusions: Children with ASD have significantly higher levels of serum and salivary IgG4 compared TD controls, suggesting an underlying defect in immune function and can be used as diagnostic marker. The levels of serum and salivary IgG4 levels show significant correlation suggesting that saliva can be used for diagnostic platforms and as non-invasive assessment tools for health monitoring.