Lachrymal isofocusing: an adapted method for diagnosis of multiple sclerosis

Background: In clinically isolated syndrome (CIS), cerebrospinal fluid (CSF) immunoglobulin G oligoclonal bands detection (OCB) is a well known predictive factor of conversion to multiple sclerosis (MS), but CSF examination is considered to be invasive. Few studies have shown the usefulness of tears-OCB detection for the diagnosis of MS. Objective: The aim of this study was to assess the predictability of tears-OCB detection in patients with CIS, for the presence of CSF-OCB. Methods: We included prospectively patients with CIS and compared the results of CSF-OCB and tears-OCB collected by a Schirmer strip. We used classic isoelectrofocusing on agarose gel followed by an immunoblotting process method. A alternative dilution technical is used for this analysis. Results: Fifty-three patients were included. CSF-OCB and tears-OCB were found in respectively 65.9% and 36.4% of patients with a concordance rate between CSF and tears of 70.5%. All patients with tears-OCB had CSF-OCB. Conclusions: According to our results, tears-OCB detection, if positive, may replace CSF-OCB detection in patients with CIS. Many lumbar punctures currently realized in this objective could thus be avoided.