Disease activity impacts disability progression in primary progressive multiple sclerosis.

BACKGROUND: Although solid information on the natural history of primary progressive multiple sclerosis (PPMS) is available, evidence regarding impact of disease activity on PPMS progression remains controversial. OBJECTIVE: To describe the clinical characteristics, presence or absence of MRI activity, and natural history of a PPMS cohort from two referral centers in Argentina and assess whether clinical and/or radiological disease activity correlated with disability worsening. METHODS: Retrospective study conducted at two MS clinics in Buenos Aires, Argentina, through comparative analysis of patients with and without evidence of disease activity. RESULTS: Clinical and/or radiologic activity was presented in 56 (31%) of 178 patients. When stratified by age at onset, we found that for every 10 years of increase in age at onset, risk of reaching EDSS scores of 4 and 6 increased by 26% and 31%, respectively (EDSS 4: HR 1.26, CI 95%: 1.06-1.50; EDSS 6: HR 1.31, CI 95%: 1.06-1.62). Patients who presented clinical exacerbations reached EDSS scores of 6, 7 and 8 faster than those without associated exacerbations (p = 0.009, p = 0.016 and p = 0.001, respectively). Likewise, patients who presented gadolinium-enhancing lesions during the course of disease reached EDSS scores of 7 earlier (p = 0.002). CONCLUSION: Older age at onset and presence of clinical and/or radiological disease activity correlated with accelerated disability progression in this cohort of PPMS patients.

Brain and spinal cord lesion criteria distinguishes AQP4-positive neuromyelitis optica and MOG-positive disease from multiple sclerosis.

OBJECTIVE: Test the ability of a brain and spinal cord MRI criteria to differentiate neuromyelitis optica spectrum disorders and MOG-disease from MS. MRI criteria was further tested in patients with CIS and pediatric MS. BACKGROUND: MOG-disease and neuromyelitis optica spectrum disorders can present clinical and radiological features strikingly similar to those of MS. Previously, diagnostic criteria based on brain MRI have been proposed to distinguish between these demyelinating diseases (Matthews-Jurynczik criteria), but spinal cord imaging and its relevance in CIS have not been evaluated. Simple brain and spinal cord MRI criteria may help separate these three inflammatory CNS diseases both in adults and children, aiding in early diagnostic decision-making, such as need for antibody testing. DESIGN/METHODS: We included 150 participants (23 with aquaporin-4-positive neuromyelitis optica spectrum disorder, 14 with MOG-disease, 20 with aquaporin-4-negative neuromyelitis optica spectrum disorder, 48 with adult-onset relapsing remitting MS, 24 with pediatric-onset MS and 21 with clinically isolated syndrome). Brain and spinal cord MRI scans were anonymised and scored by 2 separate raters, based on two sets of criteria: one previously described by Matthews and colleagues (including presence of at least one lesion adjacent to the body of lateral ventricle and in the inferior temporal lobe, or presence of subcortical U-fiber lesion or a Dawson's finger-type lesion), and an extended version including spinal cord features (non-longitudinally extensive cervical lesion). RESULTS: Extended MRI brain and spinal cord lesion criteria were able to separate adult-onset relapsing remitting MS with 100% sensitivity and 87% specificity from aquaporin-4-positive neuromyelitis optica spectrum disorder; and with 100% sensitivity and 79% specificity from MOG-disease. Additionally, brain and spinal cord criteria showed 100% sensitivity and specificity in patients presenting optic neuritis. Brain and spinal cord criteria were less sensitive in patients with CIS and in pediatric MS patients. CONCLUSIONS: Our data suggest radiological criteria can be useful to separate MS from MOG- and aquaporin-4-positive neuromyelitis optica spectrum disorders, in particular in patients with optic neuritis. Further work is needed to support their use in CIS.

Antigen microarrays identify CNS-produced autoantibodies in RRMS.

OBJECTIVE: Multiple sclerosis (MS) is characterized by the local production of antibodies in the CNS and the presence of oligoclonal bands in the CSF. Antigen arrays allow the study of antibody reactivity against a large number of antigens using small volumes of fluid with greater sensitivity than ELISA. We investigated whether there were unique autoantibodies in the CSF of patients with MS as measured by antigen arrays and whether these antibodies differed from those in serum. METHODS: We used antigen arrays to analyze the reactivity of antibodies in matched serum and CSF samples of 20 patients with untreated relapsing-remitting MS (RRMS), 26 methylprednisolone-treated patients with RRMS, and 20 control patients with other noninflammatory neurologic conditions (ONDs) against 334 different antigens including heat shock proteins, lipids, and myelin antigens. RESULTS: We found different antibody signatures in matched CSF and serum samples The targets of these antibodies included epitopes of the myelin antigens CNP, MBP, MOBP, MOG, and PLP (59%), HSP60 and HSP70 (38%), and the 68-kD neurofilament (3%). The antibody response in patients with MS was heterogeneous; CSF antibodies in individual patients reacted with different autoantigens. These autoantibodies were locally synthesized in the CNS and were of the immunoglobulin G class. Finally, we found that treatment with steroids decreased autoantibody reactivity, epitope spreading, and intrathecal autoantibody synthesis. CONCLUSIONS: These studies provide a new avenue to investigate the local antibody response in the CNS, which may serve as a biomarker to monitor both disease progression and response to therapy in MS.