Predicting multiple sclerosis at optic neuritis onset

Development of a Prognostic Model for Predicting Multiple Sclerosis After Optic Neuritis: A Secondary Analysis of Data From the Optic Neuritis Treatment Trial

BACKGROUND

Optic neuritis can be the initial manifestation of multiple sclerosis (MS). The purpose of this study was to develop a prognostic model for predicting the risk of MS development among patients with optic neuritis.

METHODS

The data from 388 patients with optic neuritis were retrieved from the Optic Neuritis Treatment Trial (ONTT). Cox proportional hazards regression analysis was used to develop a prognostic model. The performance of the model was assessed by using Harrell's C-index and calibration curves. The rates of MS development were estimated using the Kaplan-Meier method.

RESULTS

Among the enrolled subjects, a total of 154 (39.7%) patients developed clinically definite MS during a median follow-up period of 15.8 years (interquartile range, 7.2-16.9 years). The factors associated with the development of MS were the presence of brain lesions as on baseline MRI, previous nonspecific neurologic symptoms, commencing low-dose corticosteroids treatment, ocular pain, and absence of optic disc/peripapillary hemorrhage. After incorporating these 5 factors into the prognostic model, a C-index of 0.72 (95% confidence interval [CI], 0.69-0.76) and good calibration curves were obtained. The C-index of the model was significantly higher than the C-indexes of any single factor (P < 0.001 in all cases). The model was able to stratify the ONTT patient cohort into 3 risk groups with significantly different intergroup rates of developing MS (rates for developing MS within a 15-year period: high-risk group, 75.7% [95% CI, 65.6%-82.9%], intermediate-risk group, 44.7% [95% CI, 31.4%-55.4%]; and low-risk group, 20.8% [95% CI, 14.2%-26.8%]; log-rank P < 0.001).

CONCLUSIONS

This prognostic model had a better prediction ability when compared with the standard practice that relies solely on using brain lesions on MRI. It can, therefore, help guide decision-making to initiate earlier disease-modifying therapy for patients with optic neuritis at risk of developing MS.

Cerebrospinal fluid analysis

The cerebrospinal fluid (CSF) is a bodily fluid, which is both easily accessible and the most proximate to the pathological alterations of multiple sclerosis (MS). Consequently, the analysis of this fluid provides an important window into the pathological underpinnings of this disease. For example, for years, it has been known that the CSF of MS patients contains oligoclonal gamma immunoglobulins (IgG), which are synthesized within the central nervous system and presumably relate to the immune dysfunction, which is characteristically found in MS. This insight has lead to the introduction of highly-effective anti-B-cell therapies into the field of MS therapeutics. Moreover, the presence of an oligoclonal IgG response in the CSF, although not specific for MS, is a very sensitive finding and, as a result, its presence can be quite helpful for establishing an MS diagnosis in the right clinical context. In addition, this finding has predictive value. Thus, patients without a definite diagnosis who have CSF IgG bands are significantly more likely to develop definite MS compared to those patients without such a banding pattern. Other biological molecules can also be found in the CSF including neurofiliment, myelin basic protein (MBP), glial fibrillary acidic protein (GFAP), tau, neuronal cell adhesion molecule (NCAM), and the growth associated protein (GAP-43). However, the value of measuring these (and other) CSF constituents for both diagnostic and prognostic purposes and for following response to therapy is still to be determined.

Clinically isolated syndromes suggestive of multiple sclerosis: an optical coherence tomography study

BACKGROUND

Optical coherence tomography (OCT) is a simple, high-resolution technique to quantify the thickness of retinal nerve fiber layer (RNFL), which provides an indirect measurement of axonal damage in multiple sclerosis (MS). This study aimed to evaluate RNFL thickness in patients at presentation with clinically isolated syndromes (CIS) suggestive of MS.

METHODOLOGY

This was a cross-sectional study. Twenty-four patients with CIS suggestive of MS (8 optic neuritis [ON], 6 spinal cord syndromes, 5 brainstem symptoms and 5 with sensory and other syndromes) were prospectively studied. The main outcome evaluated was RNFL thickness at CIS onset. Secondary objectives were to study the relationship between RNFL thickness and MRI criteria for disease dissemination in space (DIS) as well as the presence of oligoclonal bands in the cerebrospinal fluid.

PRINCIPAL FINDINGS

Thirteen patients had decreased RNFL thickness in at least one quadrant. Mean RNFL thickness was 101.67±10.72 µm in retrobulbar ON eyes and 96.93±10.54 in unaffected eyes. Three of the 6 patients with myelitis had at least one abnormal quadrant in one of the two eyes. Eight CIS patients fulfilled DIS MRI criteria. The presence of at least one quadrant of an optic nerve with a RNFL thickness at a P<5% cut-off value had a sensitivity of 75% and a specificity of 56% for predicting DIS MRI.

CONCLUSIONS

The findings from this study show that axonal damage measured by OCT is present in any type of CIS; even in myelitis forms, not only in ON as seen up to now. OCT can detect axonal damage in very early stages of disease and seems to have high sensitivity and moderate specificity for predicting DIS MRI. Studies with prospective long-term follow-up would be needed to establish the prognostic value of baseline OCT findings.

Accuracy of diagnostic tests in multiple sclerosis--a systematic review

New diagnostic criteria for multiple sclerosis (MS) have been recently proposed and further updates are upcoming. This systematic literature review summarizes diagnostic studies in suspected MS to clarify the value of diagnostic tests. We included studies of at least 40 patients followed up for 2 years. All studies are limited by the fact that no gold standard to validate diagnostic tests is available. A second relapse is used as a surrogate in relapsing-remitting MS, but long follow-up of at least 5 years is necessary to detect all cases. Many studies showed selection bias, partly because of the vague definition of a clinically isolated syndrome. Based on these limitations, sensitivity of magnetic resonance imaging (MRI) criteria was between 35% and 100%, and specificity was between 36% and 92%. Cerebrospinal fluid (CSF) oligoclonal banding showed sensitivities between 69% and 91% with specificities between 59% and 94%. Combination studies of MRI and CSF indicate enhanced sensitivity (56-100%) and specificity (53-96%). Studies on evoked potentials did not justify conclusions about their value. A combination of simplified MRI criteria with CSF might be the best approach for an early MS diagnosis. However, the value of a very early diagnosis stays questionable as patients' benefit of new diagnostic criteria has never been addressed.

Oligoclonal bands predict multiple sclerosis after optic neuritis: a literature survey

BACKGROUND

Multiple sclerosis (MS) is an autoimmune disease resulting in inflammation and demyelination of neurones in the central nervous system (CNS). The first sign of MS is often monosymptomatic optic neuritis (MON). Cerebrospinal fluid from a patient with MS analysed by electrophoresis often shows a split to form so called oligoclonal bands (OCBs). OCBs consist of proteins from activated lymphocytes and plasma cell clones.

OBJECTIVES

The aim of this study was to review the published literature on OCBs in MON patients and perform a meta-analysis of the studies in order to assess the utility of OCB determination in patients with MON in the prediction of their risk of MS.

METHODS

Review and meta-analysis of the results of 10 published studies.

RESULTS

OCBs as a predictive test had a sensitivity of 73-100% (mean 88.5%), a specificity of 41-90% (mean 57%) and OR-values between 2.75 and 171 (mean 34.2). The areal under the summary receiver operator characteristic (ROC) curve was 0.89 (unweighted) and 0.82 (weighted). The studies showed large heterogeneity in the diagnostic accuracy.

CONCLUSION

This literature-based meta-analysis provides evidence that OCBs may have a high predictive value for the development of MS in patients with MON. Standardization of laboratory methods and diagnostic criteria would help bring out the full clinical potential of the test. To elucidate the predictive value of OCBs versus MRI, we recommend that a similar meta-analysis of studies of MRI in MON be performed.

Season of birth and multiple sclerosis in Sweden

OBJECTIVE

To estimate the risk of multiple sclerosis (MS) by month of birth in Sweden.

MATERIALS AND METHODS

Cases (n = 9361) were obtained from the Swedish MS Registry. All births in Sweden 1900-2007 served as controls (n = 12,116,853). The risk of MS was analyzed for each month of birth separately compared with birth during the other 11 months.

RESULTS

More (11%) cases with MS than expected were born in June. Fewer (8% and 10%) cases with MS than expected were born in December and January (non-significant after correction for multiple analyses). More (5%) cases with MS than expected were born in February-July as compared with August-January.

CONCLUSIONS

This study supports previous results suggesting an association between the risk of MS and the season of birth. Decreased exposure to sun in the winter leading to low vitamin D levels during pregnancy is a possible explanation that needs further research.

Season of birth and multiple sclerosis in Sweden

OBJECTIVE

To estimate the risk of multiple sclerosis (MS) by month of birth in Sweden.

MATERIALS AND METHODS

Cases (n = 9361) were obtained from the Swedish MS Registry. All births in Sweden 1900-2007 served as controls (n = 12,116,853). The risk of MS was analyzed for each month of birth separately compared with birth during the other 11 months.

RESULTS

More (11%) cases with MS than expected were born in June. Fewer (8% and 10%) cases with MS than expected were born in December and January (non-significant after correction for multiple analyses). More (5%) cases with MS than expected were born in February-July as compared with August-January.

CONCLUSIONS

This study supports previous results suggesting an association between the risk of MS and the season of birth. Decreased exposure to sun in the winter leading to low vitamin D levels during pregnancy is a possible explanation that needs further research.

Optic neuritis and the neuro-ophthalmology of multiple sclerosis

Multiple sclerosis (MS) is the most common cause of neurological disability in young adults. Since approximately 40% of the brain is devoted to vision, demyelination commonly affects visual function, resulting in a myriad of neuro-ophthalmic symptoms. In this chapter, we examine the seminal afferent and efferent neuro-ophthalmological manifestations of MS, highlighting those history and examination findings critical for the diagnosis and treatment of various visual and ocular motor disorders. Among the topics, a special emphasis will be placed on optic neuritis, the most common clinically isolated demyelinating syndrome. This chapter focuses on the evaluation and treatment of visual sensory and oculomotor disorders in MS. The objective is to provide the reader with a working model for enhancing their care of patients with demyelinating disease.

Prognostic Factors in Multiple Sclerosis

Prognostic factors to determine the patient's likelihood of developing MS are important for several reasons. Prognostic factors are important to the patient who wants to be informed about his/her prospects, to the clinician who needs to individuate the patients who deserve immune treatments, and to the researcher who needs to improve the design and the analysis of the therapeutic trials. In addition, with the development of new immune therapies, whose early use is strongly encouraged, it is crucial to dispose of reliable clinical predictors to identify the patients who are candidates for early or aggressive therapies. Several studies have indicated that a poor prognosis is related to male gender; a late age at onset; motor, cerebellar, and sphincter involvement at onset; a progressive course at onset; a short inter-attack interval; a high number of early attacks; and a relevant early residual disability. Paraclinical support for MS prognosis is given by imaging techniques, cerebrospinal fluid analysis, and evoked potential examinations. The most sensitive paraclinical test to predict conversion from suspected demyelinating disease to definite MS is MRI.

Cerebrospinal fluid T cell clones from patients with multiple sclerosis: recognition of idiotopes on monoclonal IgG secreted by autologous cerebrospinal fluid B cells

Due to somatic recombination and hypermutation, Ig variable heavy (V(H)) and light (V(L)) regions contain unique immunogenic determinants, idiotopes (Id), which can stimulate T cells. To address the relevance of this in a human disease, monoclonal IgG (mAb)-secreting B cell clones were established from the cerebrospinal fluid (CSF) of two patients with multiple sclerosis (MS). HLA-DR-restricted CD4(+) T cell lines and clones from CSF of both patients specifically recognized autologous CSF mAb. The CSF T cell clones produced IFN-gamma; some also produced TNF-alpha, IL-10 and IL-5. V(H) and V(L) on the monoclonal IgG derived from CSF B cells expressed amino acid replacements due to somatic mutations. A T cell epitope was mapped to a V(H) framework region, where an amino acid replacement was critical for the T cell recognition. The finding of Id-specific T cells and Id-bearing B cells in the CSF indicates that they coexist within the diseased organ, and provide a basis for the study of Id-driven T-B cell collaboration in a human autoimmune disease.

Predicting the Outcome of Optic Neuritis

BACKGROUND

Multiple sclerosis (MS) is a common disease with considerable risk for disability. Optic neuritis (ON) is a common first symptom of MS but it can also remain an isolated episode. Therefore, predicting the outcome of ON has gained in importance, particularly in light of current discussions of early disease modifying treatments in individuals at risk of developing MS. We reported previously on our cohort of 86 patients with acute monosymptomatic unilateral ON of whom 33 had progressed to MS after up to 18 years. Three patients had died. The present study extends the observation period to 31 years.

METHODS

Patients were followed for up to 31 years or until a diagnosis of MS was made. Cerebrospinal fluid (CSF) was examined at onset. HLA class I and II antigens were determined. Magnetic Resonance Imaging (MRI) was performed during follow up.

FINDINGS

Only one of 50 patients at risk developed clinical manifestations of MS during the extended follow up period. The estimated 15-year-risk of MS was 40 % (confidence interval [CI] 31%-52%). Most cases, 20 of 34 or 60%, occurred within three years. Among factors present at onset, CSF with mononuclear pleocytosis and/or oligoclonal Ig increased the risk for subsequent MS significantly, 49% (CI 38%-65%) compared with 23 % (CI 12%-44%) for those with normal CSF, p=0.02. Younger patients and those with winter onset also had greater risk. Recurrence of ON similarly elevated the risk significantly, p<0.001. After 19-31 years MRI lesions suggestive of demyelinating disease were detected in 20 of 30 individuals although no clinical manifestations of MS had occurred.

CONCLUSION

The risk of MS in this large population-based prospective ON patient series was 40% and significantly higher in those with inflammatory CSF abnormalities at onset. Clinically silent MRI lesions suggestive of MS were detected in a majority of those with "ON-only". This finding should be taken into account when discussing prognosis and early intervention in patients with clinically isolated ON.

B-lymphocyte and plasma cell clonal expansion in monosymptomatic optic neuritis cerebrospinal fluid

The CD19+ B-lymphocyte and CD138+ plasma cell repertoires in cerebrospinal fluid from four patients with monosymptomatic optic neuritis (ON) were analyzed by single-cell reverse transcriptase polymerase chain reaction. Amplified heavy (H)- and light (L)-chain antibody segments were sequenced and used to identify the rearranged germline and J segment of closest homology. Both the B-cell and plasma cell repertoires from ON cerebrospinal fluid demonstrated significant clonal expansion. Up to 75% of the amplified H- and L-chain sequences were contained in overrepresented populations and were somatically mutated, consistent with an antigen-targeted response. The relationship between clonal populations within the CD19+ B lymphocyte and CD138+ plasma cell populations suggests ongoing mutational pressure to refine antigen binding. Our observations demonstrate that an antigen-driven clonal B-lymphocyte and plasma cell response is prominent in the initial stages of central nervous system demyelination and suggest that detection of the disease-relevant antigens in ON may bear on the inciting antigens in chronic inflammatory disorders such as multiple sclerosis.