Limbic encephalitis in children and adolescents.

OBJECTIVE: Limbic encephalitis is rare in people <18 years of age and rarely given a formal diagnosis. DESIGN: Retrospective study on presentation and outcome of children and adolescents with the clinico-radiological syndrome of limbic encephalitis tested for specific neuronal autoantibodies (Abs) over 3.5 years. SETTING: Assessment, diagnosis, treatment and follow-up at 12 neuropaediatric and neurological departments in Europe, with Abs determined in Bonn, Germany and Oxford, UK. PATIENTS: Ten patients <18 years of age who presented with a disorder mainly affecting the limbic areas of <5 years' duration with MRI evidence of mediotemporal encephalitis (hyperintense T2/FLAIR signal, resolving over time). RESULTS: Median age at disease onset was 14 years (range 3-17). Eight patients had defined Abs: one each with Hu or Ma1/2 Abs, four with high titre glutamic acid decarboxylase (GAD) Abs, two of whom had low voltage-gated potassium channel (VGKC) Abs and two with only low titre VGKC Abs. A tumour was only found in the patient with Hu Abs (a neuroblastoma). After a median follow-up of 15 months with corticosteroid or intravenous immunoglobulin treatment, starting after a median of 4 months, two patients recovered, eight remained impaired and one died. CONCLUSIONS: Limbic encephalitis is a disease that can occur in childhood or adolescence with many of the hallmarks of the adult disorder, suggesting that both result from similar pathogenic processes. Since most of the cases were non-paraneoplastic, as now also recognised in adults, more systematic and aggressive immunotherapies should be evaluated in order to improve outcomes.

Topiramate in the treatment of highly refractory patients with Dravet syndrome.

The purpose of this study was to assess the effectiveness and tolerability of topiramate (TPM) as add-on therapy in children with Dravet syndrome and considered unsatisfactorily controlled using stiripentol. All the 36 patients having been treated with TPM in our centre in 2001 were retrospectively evaluated. Seventy percent of them still received stiripentol when TPM was introduced. The association of both drugs did not need any particular adaptation of dosages. The mean TPM follow-up was 13.3 months (4-25 months) and the mean optimal TPM dose was 3.2 mg/kg/d (0.6-9.2 mg/kg/d). Twenty eight children (78 %) showed more than 50 % reduction in the frequency of generalized tonic-clonic seizures and status epilepticus (SE), whereas 8 % had more than 50 % increase. Six patients (17 %) remained seizure-free for at least 4 months. The most frequently reported side-effects were gastrointestinal and behavioural disturbances. TPM had to be stopped in 17 % of patients, because of poor tolerability and/or lack of efficacy. Topiramate seems therefore to be helpful in Dravet syndrome, even in patients not satisfactorily controlled by stiripentol. Both drugs can be easily and safely associated.