| Background: Autism spectrum disorder (ASD) is a spectrum of behavioral
anomalies characterized by impaired social interaction and communication, often
accompanied by repetitive and stereotyped behavior. The condition manifests within
the first 3 years of life and persists into adulthood. There are numerous hypotheses
regarding the etiology and pathology of ASD, including a suggested role for immune
dysfunction. While immune system abnormalities have been reported in children
with autistic disorder, there is little consensus regarding the nature of these
differences which include both enhanced autoimmunity and reduced immune
function. It has long been known that extensive interactions occur between the
immune system and neuronal system/brain, and that normal neurodevelopment is
contingent upon an appropriate interaction with the immune system. Objectives: the
aim of the present study was to evaluate the cell mediated and humoral immunity of
children with autism through evaluation of the serum antibody levels of
immunoglobulin (IgG, IgM, IgA), also we evaluated the T helper and T suppressor
cells (CD4 and CD8 T cell subpopulations) and CD4/CD8 ratio in children with
autism and compared with the healthy control children. Methods: This study was
carried out in the Psychiatry Unit, Department of Pediatrics, Tanta University
Hospital. Thirty children with autism (24 males, 6 females) newly diagnosed were
included in the study, their age range was (3-9 years) with the mean age of 5?1.8
years. Childhood Autism Rating Scale (CARS) was used for the diagnosis of autism.
Diagnosis of autism was based also, on the criteria for the diagnosis of autism that
are set out in the Diagnostic and Statistical Manual of Mental Disorders DSM-IVTR
(Fourth Edition, Text Revision). The intial Childhood Autism Rating Scale
(CARS) score for these children was ?30, as children with a CARS score ?30 were
considered to have autism. Intial CARS score range for children with autism was
(31-60). The control group consisted of thirty healthy children (10 females, 20
males). Their age range was (2-10 years) and the mean age was 5.3? 2.4 years.
Results: Children with autism had significantly lower serum levels of IgG, IgA and
IgM compared to the control children p?0.001. Also children with autism had
significantly lower numbers of CD4 cells with increased CD8+ T cell
subpopulations and decreased CD4+/CD8+ ratio. Conclusion: Children with
autism have significantly reduced levels of serum IgG, IgA and IgM compared to
the control children, suggesting an underlying defect in the immune function, also
the cell-mediated immunity is impaired as evidenced by low numbers of CD4+ cells
and increased CD8+ T cell subpopulations and decreased CD4+/CD8+ ratio. |