Cerebrospinal fluid CD4+ /CD8+ ratio in diagnosing neurosarcoidosis.

The study confirms that increased CSF CD4+ /CD8+ ratio is associated with neurosarcoidosis but cannot alone distinguish the conditions from other neurological diagnoses. However, a ratio below <5 combined with an absence of pleocytosis in CSF yields a negative predictive value (NPV) of 88% suggesting a role for the analysis in differential diagnosing neuroinflammatory conditions.