The spectrum of postinfectious encephalomyelitis

The medical records of 52 consecutive patients diagnosed with postinfectious encephalitis/encephalomyelitis during the period from 1980 to 1998, including 29 males and 23 females, were reviewed. These patients were divided into three groups according to their clinical and neurodiagnostic characteristics: (1) group I: postinfectious encephalitis, 38 patients; (2) group II: acute disseminated encephalomyelitis (ADEM), 13 patients; (3) group III: multiphasic disseminated encephalomyelitis (MDEM), one patient. Fever, headache/vomiting, seizure and disturbance of consciousness were common clinical features in all patients, while pictures of pyramidal, extrapyramidal, brainstem, and spinal cord lesions were more often found in the group II and group III patients than in the group I patients. Magnetic resonance imaging (MRI) revealed abnormal lesions in six (60%) of ten group I patients, but all group II (n=7) and group III (n=1) patients who received MRI study showed abnormal signals in various regions of the brain including the cerebral hemisphere, basal ganglia, brainstem and cerebellum. Patients with ADEM and MDEM had a longer clinical course and more neurological sequelae than group I patients. This study demonstrates the breadth of the clinical spectrum of postinfectious encephalomyelitis. Thorough clinical observations and appropriate neurodiagnostic studies such as MRI are crucial for the diagnosis.