BACKGROUND AND PURPOSE:The exact prevalence of WM signal abnormalities in healthy relatives of MS patients and their impact on disease development has not been fully elucidated. The purpose of this study was to compare WM signal abnormality characteristics and the prevalence of radiologically isolated syndrome in healthy control subjects selected randomly from the population with the healthy relatives of patients with MS.

Combination of cVEMP and oVEMP in MS patients allows better estimation of brainstem lesions.

Interpretation of the oVEMP and cVEMP results in the form of the VEMP score enables better evaluation of brainstem involvement than either of these evoked potentials alone and correlates well with disability.

Objective To evaluate clinical and laboratory effects of delaying ocrelizumab infusions during the COVID-19 pandemics in people with multiple sclerosis (pwMS). Methods We have retrospectively searched our electronic database and identified 33 pwMS who had a delay in treatment due to COVID-19 pandemics. The following data were extracted: age, sex, multiple sclerosis (MS) phenotype: relapsing-remitting (RRMS) or primary progressive multiple sclerosis (PPMS), disease duration, Expanded Disability Status scale (EDSS), previous disease modifying therapy (DMT), number of ocrelizumab cycles prior to the lockdown, dates of first ocrelizumab infusion, last ocrelizumab infusion prior to the lockdown and delayed ocrelizumab infusion after the lockdown. Flow cytometry results, relapses and EDSS progression prior to the delayed ocrelizumab infusion after the lockdown were extracted. Results The mean time between two ocrelizumab infusion during the lockdown was 7.72±0.64 (range 6.07 to 8.92) months. The mean time between last ocrelizumab infusion and the lymphocyte sampling prior to post COVID infusion was 6.59±0.95 (range 5.18 to 8.49) months. In this period, none of the studied patients had a relapse. In a multivariable linear regression analysis, time from last ocrelizumab infusion to lymphocyte sampling prior to the next infusion was the only significant predictor for CD19 + B cells count, when corrected for the number of previous ocrelizumab cycles and MS phenotype (RRMS or PPMS) (B=7.981, 95% C.I. 3.277-12.686, p=0.002). Conclusions We have not shown clinical consequences of delaying ocrelizumab due to COVID-19 pandemics. However, the delay in dosing of ocrelizumab was an independent predictor of repopulation of B cells.