Clinical analysis of acute disseminated encephalomyelitis in 44 cases

Objective To investigate the clinical features in 44 patients with acute disseminated encephalomyelitis (ADEM). Methods Consecutive ADEM patients admitted to Neurology Department of the Third Affiliated Hospital of Sun yat-sen University during August 2009 to July 2014 were enrolled.Clinical and laboratory data of the patients were reviewed and analyzed. Results Forty-four patients with ADEM based on the 2012 criteria were recruited, including 23 male and 21 female; 9 children, 11 teenagers and 24 adults.There were 23 monophasic ADEM (23/44, 52%) and 21 multiphasic ADEM (21/44, 48%). Fourteen patients (31.8%) had definite incentive factors within 2 weeks preceding the disease onset.The commonest presenting symptoms were fever (20/44, 45%), mental disorder (18/44, 41%), disturbance of consciousness (17/44, 39%) and seizure (12/44, 27%). The average EDSS score was (4.3±1.3), and the average mRS score was (2.7±0.9). Abnormal autoimmune antibodies were detected in 10 patients.Two patients were positive for NMO-IgG, and three patients were positive for oligoclonal bands.On MRI scanning, small lesions were observed in 18 of 44 patients (18/44, 41%); large confluent white matter lesions in 10 patients (10/44, 23%); symmetric bithalamic involvement in 12 patients (12/44, 27%). Patients were mainly treated with intravenous corticosteroids (40/44, 90.9%) and immunoglobulin G ( 13/44, 29.5%) in acute phase.Regular follow-up performed in 29 patients (65.9%), and the average follow-up time was (4.2±2.3) year.A monophasic course was found in 10 patients, and multiphasic course in 19 patients.After (2.5±2.3) years, patients with multiphasic ADEM experienced their first clinical relapse, and the relapse frequency was (3.3±1.4). The average EDSS score was (3.9±2.2), and the mRS score was (2.2±1.3) in their latest relapse.In follow-up MRI for (5.3±1.9) years, lesions in 18 patients (62.1%) were partially ameliorated, while 6 patients (20.7%) persisted, and new lesions appeared in 5 patients (17.2%). For the 13 multiphasic patients with regular treatment, intravenous corticosteroids (13/13, 100.0%) and immunoglobulin G (7/13, 53.8%) were still important treatments in the acute phase, while oral steroids (12/13, 92.3%) plus immunosuppressants including azathioprine, tacrolimus, cyclosporine and rituximab were chosen in the remission phase. Conclusions ADEM is not uncommon in adults, presenting with multiphasic course, encephalopathy features and disseminated lesions on MRI.As it shows very heterogeneous characteristics, ADEM is best viewed as a "syndrome" rather than a specific disorder. Key words: Acute disseminated encephalomyelitis; Clinical; Magnetic resonance imaging