Flow cytometric analysis of T cell/monocyte ratio in clinically isolated syndrome identifies patients at risk of rapid disease progression

Background: Multiple sclerosis is a chronic inflammatory central nervous system disease diagnosed by clinical presentation and characteristic magnetic resonance imaging findings. The role of cerebrospinal fluid (CSF) analysis has been emphasized in particular in the context of differential diagnosis in patients with a first episode suggestive of multiple sclerosis. Objective: We investigated here the potential additional value of analysis of CSF cellularity by fluorescence activated cell sorting (FACS) in the setting of a routine diagnostic work-up in our inpatient clinic. Methods: CSF cells from back-up samples from patients with suspected chronic inflammatory central nervous system disorder were analyzed by FACS and correlated with clinical data, magnetic resonance imaging findings and oligoclonal band status. Results: We found distinct changes of T cell/monocyte (CD4/CD14) and B cell/monocyte (CD20/CD14) ratios between clinically isolated syndrome (CIS)/multiple sclerosis and other neurologic diseases or other inflammatory neurologic diseases. In particular, patients with a rapid transition from CIS to multiple sclerosis had an elevated CD4/CD14 ratio. A subgroup analysis showed diagnostic value of CD4/CD8 ratio in the differential diagnosis of CIS/multiple sclerosis to neurosarcoidosis. Conclusion: The diagnostic and prognostic accuracy of autoimmune neuroinflammatory diseases can be improved by FACS analysis of CSF cells.