Immune System Impairments

Infants with Down syndrome may have a deficiency of specific immunoglobulins, especially IgG. They also have a higher risk of cell-mediated immune disorders. The white blood cells in youngsters with Down syndrome often fail to travel as quickly as they should to the site of infections. This impairs the body's normal immune response to bacteria.

Colvin & Yeager (2017) list the following immune system disturbances as occurring in Down syndrome individuals.

• Mild-to-moderate reduction in T-cell counts
• Mild-to-moderate reduction in B-cell counts
  
• Absence of normal lymphocyte expansion in infancy
  
• Thymus size is smaller than age-matched controls
  
• Mild-to-moderate reduction in naive T-cell percentages, with the corresponding reduction of T-cell excision circles
  
• Suboptimal antibody responses to immunizations
  
• Decreased total and specific immunoglobulin A in saliva
  
• Decreased neutrophil chemotaxis

For these reasons, professional guidelines for treating common infections may differ for children with Down syndrome than for other children. Pediatricians may prescribe antibiotics sooner and in less apparent scenarios than for children with normal immune system function.

Children with Down syndrome are also at increased risk for autoimmune disorders, including hypothyroidism and diabetes mellitus, as well as allergies. Nurses can play a crucial role in the early detection of these disorders.