Repeated lumbar puncture in search of oligoclonal bands – What is the yield?

Background: Cerebrospinal fluid (CSF) oligoclonal bands (OCBs) are immunoglobulins that represent intrathecal synthesis during central nervous system infection or inflammation. As repeated lumbar puncture (LP) is usually not performed unless clinically indicated, there is very limited data on the natural history and course of OCBs status in the CSF, its relation to disease activity, duration of persistence, and the rate of either CSF conversion of OCBs or disappearance. Methods: We retrospectively collected data from adult patients with various neurological syndromes who had repeated CSF samplings. OCBs were analyzed by agarose gel electrophoresis or by isoelectric focusing. Results: During the years 2010–2020, we identified 48 patients with at least two CSF OCBs results in Rabin Medical Center. These included 11 patients with Multiple Sclerosis, ADEM and NMOSD (one patient each), 7 patients with unspecified demyelinating disease, 4 with optic neuropathy, 15 patients with unknown diagnosis. Overall, 6/48 (12.5%) patients had change in OCBs status between first and second LP's. Four (8.33%) patients changed OCBs from positive to negative, and two patients (4.2%) from negative to positive. There was no significant difference in demographic, disease category, CSF constituents or time interval to second LP between patients who changed their OCBs status to those who did not. Conclusion: Repeated LP for OCBs analysis in our cohort did not yield a practical benefit. The conversion rate of OCBs status was low (12.5%) and in most cases did not lead to a change in the final diagnosis or patient's clinical management.