CD4 and opsoclonus-myoclonus syndrome: Evidenceof T cell population expansion in the CSF of children with OMS has changedpeople’s minds(38).Rapid increases in CD4+ cell counts in HIV-infected patients support the role ofT cells in OMS(39).Although elevated neopterin in CSF does not have the sensitivity to be abiomarker, it can support T-cell activation and cell mediated immunity inOMS(40).