Multiple sclerosis in children: an update on clinical diagnosis, therapeutic strategies, and research

Central nervous system vasculitis in adults and children

Primary angiitis of the central nervous system (PACNS) is an inflammatory brain disease targeting the cerebral blood vessels, leading to a wide spectrum of signs and symptoms, including neurologic deficits, cognitive dysfunction, and psychiatric symptoms. The inflammation could be reversible if diagnosed and treated early. The diagnosis requires the careful consideration and rapid evaluation of systemic underlying conditions and disease mimics. The differential diagnosis is distinctly different for angiography-positive and -negative PACNS subtypes and differs depending on age, so there is childhood PACNS or adult PACNS. Distinct disease subtypes have been described, with characteristic disease course, neuroimaging findings, and histopathologic features. Novel and traditional biomarkers, including von Willebrand factor antigen and cytokine levels, can help diagnose, and define subtype and disease activity. Treatment of PACNS should be tailored to the disease subtypes and clinical symptoms. Beyond immunosuppression it should include medications to control symptoms in order to support and enhance the child's or adult's ability to actively participate in rehabilitation. The mortality of PACNS has decreased; studies determining the morbidity and its determinants are urgently needed.

Neurogenic lower urinary tract dysfunction in the early disease phase of paediatric multiple sclerosis

Neurogenic lower urinary tract dysfunction (LUTD) in multiple sclerosis (MS) is highly prevalent in adults, but has not previously been described in paediatric MS. A total of 24 consecutive children with newly diagnosed MS were prospectively assessed for bladder and bowel problems early after diagnosis. Five of 24 children (21%) showed LUTD during assessment. One of these patients did not report voiding complaints. This high prevalence of LUTD indicates that all recently diagnosed patients with paediatric MS should be evaluated early in their disease and treated for urinary problems in order to prevent potential damage to the upper urinary tract.

Natalizumab in multiple sclerosis: discontinuation, progressive multifocal leukoencephalopathy and possible use in children

In the early 1990s, attention was drawn to the migration of immune cells into the central nervous system via the blood-brain barrier. The literature showed that lymphocytes binding to the endothelium were successfully inhibited by an antibody against α4β1 integrin. These biological findings resulted in the development of a humanized antibody to α4 integrin - natalizumab (NTZ) - to treat multiple sclerosis (MS). Here, we provide a systematic review and meta-analysis on the efficacy and safety of natalizumab, trying to answer the question whether its use may be recommended both in adult and in pediatric age groups as standard MS treatment. Our results highlight the improvement of clinical and radiological findings in treated patients (p < 0.005), confirming NTZ efficacy. Nevertheless, if NTZ is shown to be efficient, further studies should be performed to evaluate its safety and to target the MS profile that could benefit from this treatment.

Natalizumab in the pediatric MS population: results of the Italian registry

Background

Natalizumab is a promising option for pediatric multiple sclerosis (MS) patients with active evolution and a poor response to Interferon-beta or Glatiramer Acetate. However, no data are available in large cohorts of patients and after a long-term follow up. Our study was planned to shed lights on this topic.

Methods

A registry was established in 2007 in Italy to collect MS cases treated with Natalizumab (NA) before 18 years of age.

Results

101 patients were included (69 females), mean age of MS onset 12.9 ± 2.7 years, mean age at NA initiation 14.7 ± 2.4 years. Mean treatment duration was 34.2 ± 18.3 months.

During NA treatment, a total of 15 relapses were recorded in 9 patients, annualized relapse rate was 2.3 ± 1.0 in the year prior to NA and decreased to 0.1 ± 0.3 (p < 0.001) at last NA infusion.

Mean Expanded Disability Status Scale (EDSS) decreased from 2.6 ± 1.3 at initiation of NA to 1.8 ± 1.2 at the time of last visit (p < 0.001). At brain MRI, new T2 or Gd enhancing lesions were observed in 10/91 patients after 6 months, 6/87 after 12 months, 2/61 after 18 months, 2/68 after 24 months, 3/62 after 30 months, and 5/43 at longer follow up. At the time of last observation, 58 % of patients were free from clinical (relapses/increased EDSS) and/or MRI activity (new T2 or gadolinium-enhancing lesions). No relevant adverse events were recorded.

Discussion

NA was safe, well tolerated and very efficacious in the large majority of patients. Our data support the use of this medication in subjects with pediatric MS and an aggressive course.

Conclusions

A relevant reduction of relapse rate and EDSS was observed during NA treatment, compared to pre-treatment period. No evidence of disease activity (NEDA) occurred in 58 % of cases.

Fingolimod Prescribed for the Treatment of Multiple Sclerosis in Patients Younger Than Age 18 Years

BACKGROUND

There have been no clinical trials for approval of medications for treating multiple sclerosis in patients younger than age 18 years. All treatments are based on personal experience and data from open observational studies. Fingolimod is an oral drug for multiple sclerosis that has been shown to be efficient and safe in adults. The aim of our study is to describe patients with multiple sclerosis who started treatment with fingolimod before the age of 18 years.

PARTICIPANTS AND METHODS

Seventeen patients treated with fingolimod were identified in the Brazilian database of children and adolescents with multiple sclerosis. The average time of use of the drug was 8.6 months.

RESULTS

Fingolimod showed a good safety and efficacy profile in these patients, all of whom had very active multiple sclerosis. After starting treatment with fingolimod, only one patient had a relapse and a new lesion on magnetic resonance imaging. The patients' degree of disability did not progress. No major adverse events were reported in relation to the first dose of the drug, nor in the short- and medium-term treatment. No patient has been followed for longer than 18 months, thus limiting long-term conclusions.

CONCLUSIONS

Off-label use of fingolimod in patients younger than age 18 years may be a good therapeutic option for multiple sclerosis control.

Modelling MS: Chronic-Relapsing EAE in the NOD/Lt Mouse Strain

Modelling complex disorders presents considerable challenges, and multiple sclerosis (MS) is no exception to this rule. The aetiology of MS is unknown, and its pathophysiology is poorly understood. Moreover, the last two decades have witnessed a dramatic revision of the long-held view of MS as an inflammatory demyelinating white matter disease. Instead, it is now regarded as a global central nervous system (CNS) disorder with a neurodegenerative component. Currently, there is no animal model recapitulating MS immunopathogenesis. Available models are based on autoimmune-mediated demyelination, denoted experimental autoimmune encephalomyelitis (EAE) or virally or chemically induced demyelination. Of these, the EAE model has been the most commonly used. It has been extensively improved since its first description and now exists as a number of variants, including genetically modified and humanized versions. Nonetheless, EAE is a distinct disease, and each variant models only certain facets of MS. Whilst the search for more refined MS models must continue, it is important to further explore where mechanisms underlying EAE provide proof-of-principle for those driving MS pathogenesis. EAE variants generated with the myelin component myelin oligodendrocyte glycoprotein (MOG) have emerged as the preferred ones, because in this particular variant disease is associated with both T- and B-cell effector mechanisms, together with demyelination. MOG-induced EAE in the non-obese diabetic (NOD) mouse strain exhibits a chronic-relapsing EAE clinical profile and high disease incidence. We describe the generation of this variant, its contribution to the understanding of MS immune and pathogenetic mechanisms and potential for evaluation of candidate therapies.