Magnetic resonance imaging of experimental autoimmune encephalomyelitis in the common marmoset.

Magnetic resonance imaging (MRI) is an invaluable tool for the diagnosis and monitoring of patients with multiple sclerosis (MS) as well as for the study of the disease pathophysiology. Because of its strong clinical, radiological and histopathological similarities with the human disease, experimental autoimmune encephalomyelitis (EAE) in the common marmoset has been studied more intensively over the past several years. Here, we review the current knowledge on MRI in the marmoset EAE, and we outline the physiopathological significance and translational values of these studies with respect to MS. Accumulating evidences suggest that the application of conventional, as well as non-conventional, MRI techniques in the marmoset EAE is a promising approach to elucidate the pathological processes underlying the development of inflammatory demyelinated lesions in the central nervous system, potentially improving the identification and development of new therapeutics

Prediction of seizure recurrence risk following discontinuation of antiepileptic drugs

OBJECTIVE: Discontinuation of antiepileptic drugs (AEDs) in seizure‐free patients is an important goal because of possible long‐term side effects and the social stigma burden of epilepsy. The purpose of this work was to assess seizure recurrence risk after suspension of AEDs, to evaluate predictors for recurrence, and to investigate the recovery of seizure control after relapse. In addition, the accuracy of a previously published prediction model of seizure recurrence risk was estimated. METHODS: Seizure‐free patients with epilepsy who had discontinued AEDs were retrospectively enrolled. The frequency of seizure relapses after AED withdrawal as well as prognosis after recurrence were assessed and the predictive role of baseline clinical‐demographic variables was evaluated. The aforementioned prediction model was also validated and its accuracy assessed at different seizure‐relapse probability levels. RESULTS: The enrolled patients (n = 133) had been followed for a median of 3 years (range 0.8–33 years) after AED discontinuation; 60 (45%) of them relapsed. Previous febrile seizures in childhood (hazard ratio [HR] 3.927; 95% confidence interval [CI] 1.403–10.988), a seizure‐free period on therapy of less than 2 years (HR 2.313; 95% CI 1.193–4.486), and persistent motor deficits (HR 4.568; 95% CI 1.412–14.772) were the clinical features associated with relapse risk in univariate analysis. Among these variables, only a seizure‐free period on therapy of less than 2 years was associated with seizure recurrence in multivariate analysis (HR 2.365; 95% CI 1.178–4.7444). Pharmacological control of epilepsy was restored in 82.4% of the patients who relapsed. In this population, the aforementioned prediction model showed an unsatisfactory accuracy. SIGNIFICANCE: A period of freedom from seizure on therapy of less than 2 years was the main predictor of seizure recurrence. The accuracy of the previously described prediction tool was low in this cohort, thus suggesting its cautious use in real‐world clinical practice

Markers of JC virus infection in patients with multiple sclerosis under natalizumab therapy.

OBJECTIVE: To evaluate the frequency of JC polyomavirus (JCPyV) infection and anti-JCPyV antibodies in patients with multiple sclerosis under natalizumab therapy. METHODS: Presence of anti-JCPyV antibodies and JCPyV DNA was analyzed in 39 patients with relapsing-remitting multiple sclerosis undergoing natalizumab therapy. Anti-JCPyV antibodies were evaluated in serum by a 2-step virus-like particle-based ELISA assay (Stratify), and JCPyV DNA was evaluated in peripheral blood mononuclear cells, plasma, and urine by quantitative PCR. The anti-JCPyV antibodies were evaluated in serum samples collected at the same time or later than those collected for DNA analysis. RESULTS: JCPyV DNA was detected in 59% of patients, and anti-JCPyV antibodies were present in 67%. JCPyV DNA occurred more often in blood than in urine. Anti-JCPyV antibodies were observed in 70% of the JCPyV-infected patients, and JCPyV DNA was detected in 50% of the patients without anti-JCPyV antibodies. When JCPyV DNA was investigated in blood and urine the frequency of infection was higher than previously described. CONCLUSION: Under these experimental conditions, with respect to the observed frequency of JCPyV infection, the sensitivity of the anti-JCPyV antibody assay was lower than expected