Abstracts

Rationale: To investigate the differences of clinical characteristics between patients with ADEM associated with seizures or without seizures at the time of the first presentation.Methods: Medical records and MRI of 31 ADEM patients (male 18, female 13) were reviewed retrospectively. The patients were classified into 2 groups: 16 (51.6%) with seizure as a Group 1(G-1), and 15 (48.4%) without seizures as a Group 2 (G-2). Mean age was 6.2 years (range: 1.6 to 15) and mean follow up period was 3.8 years (range: 1 to 6). The following parameters were studied: the antecedent events, the neurological manifestations, the CSF findings, the EEG findings, the lesion sites of involvement in MRI, and the outcome. Results: 1. There was “no defined prodrome” in 8 (50.0%)out of 16 and 6 (40.4%)out of 15, the URI symptoms in 2 (12.5%) and 4 (26.7%), the nonspecific febrile illness in 3 (18.8%) and 2 (13.3%), the gastrointestinal disturbance in 3 (18.8%) and 2 (13.3%) as the antecedent events in the G-1 and G-2, one (6.7%) in the G-2 (6.7%) showed vaccination history. There were no significant differences in the antecedent events between two groups. 2. There were the hemiparesis in 10 (62.5%) and 4 (26.7%), the altered consciousness in 6 (37.5%) and 6 (40.0%), the ataxia in 5 (31.3%) and 4 (26.7%), the visual disturbance 3 (18.8%) and 1 (6.7%) and the facial nerve palsy 2 (12.5%) and 1(6.7%) as the presenting symptoms in the G-1 and G-2. There were significant differences in frequency of the hemiparesis and the visual disturbance between the two groups (P<0.05). 3. There were the CSF pleocytosis in 5 out of 16 (31.3%) and 3 out of 15 (20.0%), and the elevated protein in 2 (12.5%) and 3 (20.0%) in the G-1 and G-2. There was no significance between the two groups. 4. The EEG abnormalities were observed in 7 out of 16 (43.8%) and 2 out of 15 (13.3%) in the G-1 and G-2. There was a significant difference in the EEG abnormalities (P<0.05). 5. There were the involvements of the multi- or unifocal lesions only in the cerebral white matter (WM) in 10 of 16 (62.5%) and 13(86.7%) in the G-1 and G-2, and the involvements of the gray matter (GM) with or without WM in 6 (37.5%) and 2 (13.3%) in the G-1 and G-2. In the G-1, there was more involvement of the GM than the G-2 (P<0.05). 6. Out of 31 patients, 11 (68.6%) and 14 (86.7%) in the G-1 and G-2 made a complete recovery. There were the intractable seizures in 3 (18.8%) in the G-1, and the motor disturbance in 3 (18.6%) and 1 (6.7%) in the G-1 and G-2. There was higher rate of the complete recovery in the G-2 than G-1 (P<0.05). Conclusions: In ADEM with seizures, the hemiparesis and the visual disturbance as the presenting symptoms, the EEG abnormalities, the involvement of the GM, and the motor disturbance in outcome were more common than ADEM without seizures. Conclusively, the seizures may help to determine the prognosis of the ADEM patients.