Acquired sensory neuronopathies encompass a group of paraneoplastic, dysimmune, toxic or idiopathic disorders characterized by degeneration of peripheral sensory neurons in dorsal root ganglia. As dorsal root ganglia cannot easily be explored, the clinical diagnosis of these disorders may be difficult. The question as to whether there exists a common clinical pattern of sensory neuronopathies, allowing the establishment of validated and easy-to-use diagnostic criteria, has not yet been addressed. In this study, logistic regression was used to construct diagnostic criteria on a retrospective study population of 78 patients with sensory neuronopathies and 56 with other sensory neuropathies. For this, sensory neuronopathy was provisionally considered as unambiguous in 44 patients with paraneoplastic disorder or cisplatin treatment and likely in 34 with a dysimmune or idiopathic setting who may theoretically have another form of neuropathy. To test the homogeneity of the sensory neuronopathy population, likely candidates were compared with unambiguous cases and then the whole population was compared with the other sensory neuropathies population. Criteria accuracy was checked on 37 prospective patients referred for diagnosis of sensory neuropathy. In the study population, sensory neuronopathy showed a common clinical and electrophysiological pattern that was independent of the underlying cause, including unusual forms with only patchy sensory loss, mild electrical motor nerve abnormalities and predominant small fibre or isolated lower limb involvement. Logistic regression allowed the construction of a set of criteria that gave fair results with the following combination: ataxia in the lower or upper limbs + asymmetrical distribution + sensory loss not restricted to the lower limbs + at least one sensory action potential absent or three sensory action potentials <30% of the lower limit of normal in the upper limbs + less than two nerves with abnormal motor nerve conduction study in the lower limbs.

No abstract

The data demonstrate that in patients with paraneoplastic neurological syndromes, the neurological symptoms and survival vary with both the type of associated onco-neural antibody and the type of tumour.

IMPORTANCE The safety and efficacy of switching from natalizumab to fingolimod have not yet been evaluated in a large cohort of patients with multiple sclerosis (MS) to our knowledge.OBJECTIVE To collect data from patients with MS switching from natalizumab to fingolimod. DESIGN, SETTING, AND PARTICIPANTSThe Enquête Nationale sur l'Introduction du Fingolimod en Relais au Natalizumab (ENIGM) study, a survey-based, observational multicenter cohort study among MS tertiary referral centers. Participants were patients for whom a switch from natalizumab to fingolimod was planned. Clinical data were collected on natalizumab treatment, duration and management of the washout period (WP), and relapse or adverse events during the WP and after the initiation of fingolimod. MAIN OUTCOMES AND MEASURESOccurrence of MS relapse during the WP or during a 6-month follow-up period after the initiation of fingolimod.RESULTS Thirty-six French MS tertiary referral centers participated. In total, 333 patients with MS switched from natalizumab to fingolimod after a mean of 31 natalizumab infusions (female to male ratio, 2.36; mean age, 41 years; and Expanded Disability Status Scale score at the initiation of natalizumab, 3.6). Seventy-one percent were seropositive for the JC polyomavirus. The Expanded Disability Status Scale score remained stable for patients receiving natalizumab. Twenty-seven percent of patients relapsed during the WP. A WP shorter than 3 months was associated with a lower risk of relapse (odds ratio, 0.23; P = .001) and with less disease activity before natalizumab initiation (P = .03). Patients who stopped natalizumab because of poor tolerance or lack of efficacy also had a higher risk of relapse (odds ratio, 3.20; P = .004). Twenty percent of patients relapsed during the first 6 months of fingolimod therapy. Three percent stopped fingolimod for efficacy, tolerance, or compliance issues. In the multivariate analysis, the occurrence of relapse during the WP was the only significant prognostic factor for relapse during fingolimod therapy (odds ratio, 3.80; P = .05). CONCLUSIONS AND RELEVANCEIn this study, switching from natalizumab to fingolimod was associated with a risk of MS reactivation during the WP or shortly after fingolimod initiation. The WP should be shorter than 3 months.