Longitudinal stability of JCV antibody index in Natalizumab treated people with multiple sclerosis.

OBJECTIVE: The aim of this study was to evaluate the evolution of JCV index over time in Natalizumab treated people with multiple sclerosis. MATERIALS AND METHODS: We retrospectively reviewed antibody index values from pwMS who were treated with Natalizumab for greater than six months and had at least two antibody results available between 2011 and 2019. Survival analysis was performed on those who were JCV index value negative at baseline to evaluate time to seroconversion. In pwMS who had index values available at 48 and/or 96 months post Natalizumab initiation, t-tests were performed to evaluate change in index over time. RESULTS: 1144 JCV antibody index results were available for 132 pwMS. Median time to seroconversion based on survival analysis was 103 months. Annualised seroconversion rate was 5.8%. Initial antibody index and rate of seroconversion did not differ with regards to age or gender. Antibody index increased significantly over time on treatment for the cohort as a whole, initial antibody index (0.27) to final antibody testing (0.86), t(131)=6.45, p<.0005. There was a significant increase in those with initial positive index value, between first (0.95) and final index (2.14), t(33) = 4.85, p<.0005 over a median of 77 months. CONCLUSIONS: In those who were seronegative at baseline there is a long median duration of treatment with Natalizumab prior to seroconversion. In individuals with positive JCV antibody index at treatment initiation, antibody index increases over time.

Cognitive dysfunction in early multiple sclerosis: a review.

Cognitive impairment is a common and disabling feature of Multiple Sclerosis (MS), including early MS, and may even pre-date any physical symptoms. It contributes even more to withdrawal from work than physical disability. Here, we provide an overview of cognitive impairment in MS, particularly in early MS where it is most commonly under-reported and under-treated. We address the presenting features of CI, its impact on quality of life, and its validated assessments (in particular the use of Brief International Cognitive Assessment in MS for use in a clinical setting). We review the insights radiology has given us into the pathogenesis of cognitive impairment in MS, particularly in early CI and in cognitively preserved MS patients. We review current treatments for cognitive impairment, primarily cognitive rehabilitation. We address the evidence for its associated co-morbidities, which may exacerbate or trigger CI, and should therefore be addressed early in the disease course (smoking, alcohol, mood, fatigue and potential co-existing sleep disorders, exercise, and vitamin D). The article supports the importance for early recognition and management of cognitive impairment in MS, before it becomes an established and irreversible entity.

A role for susceptibility weighted imaging in progressive multifocal leukoencephalopathy.

We report a radiologic finding on magnetic resonance imaging (MRI) of the brain of two cases of progressive multifocal leukoencephalopathy (PML) of hypointense signal of subcortical U-fibres on susceptibility weighted (SW) sequence. The first case is a 50-year-old man recently treated with chemotherapy including rituximab for non-Hodgkin's lymphoma. The second case is a 64-year-old woman with human immunodeficiency virus (HIV) infection. Iron deposition is a likely causative factor. We propose that SWI may be especially useful in the assessment of indeterminate cases to reduce the likelihood of a missed diagnosis of PML.

Foot Drop: Looking Beyond Common Peroneal Nerve Palsy: A Neurophysiology Centre Experience.

Foot drop is a complex symptom with a considerable range in aetiology, severity and prognosis. We aim to characterise the aetiologies of foot drop and assess the diagnostic contribution of neurophysiologic testing (NCS/EMG). Retrospective review of consecutive referrals of foot drop to the Neurophysiology Department in Cork University Hospital was performed over a two year period (January 2012 to December 2013). Of a total of 59 referrals, common peroneal nerve (CPN) palsy comprised only slightly more than half of cases; 3(5%) have central origin; 3(5%) have motor neuron disease. Six (10%) have diabetes; 7(12%) have cancer; 5(8%) were bilateral. NCS/EMG altered initial working diagnosis in 14 out of 52 (27%) cases whereby initial diagnosis was provided. However one-third of all cases revealed additional coexistent pathology in an anatomic location remote to that of the primary diagnosis. Foot drop with central and proximal localisations are important and under recognised. NCS/EMG is valuable and also reveals additional pathology which warrants investigation.