Altered cellular but not humoral reactions in children with complicated enterovirus 71 infections in Taiwan

Enterovirus 71 (EV 71) infections have high neurovirulence and fatality. Im mune responses were assessed in 78 patients with EV 71 infection. EV 71 men ingoencephalitis occurred more frequently in younger children and in boys. C-reactive protein levels were not elevated, although total leukocyte count s were increased in these patients. The CD40-ligand expression on T cells s ignificantly decreased in children with meningoencephalitis (P = .041). Pol ymorphism of the cytotoxic T lymphocyte antigen-4 (CTLA-4) at position 49 o f exon 1 showed a higher frequency of G/G genotype in patients with EV 71 m eningoencephalitis than in those without meningoencephalitis (18/31 vs. 14/ 47; P = .045) and in control subjects (18/31 vs. 25/931; P = .007). Specifi c EV 71 neutralizing antibody titers were detectable but did not differ in children with and without meningoencephalitis in the acute and convalescent stages. Results from this study suggest that younger children with a certa in CTLA-4 polymorphism and altered cellular but not humoral response may be linked to EV 71 meningoencephalitis.