[Clinical features of 19 children with Bickerstaff brainstem encephalitis]

Objective: To summarize the clinical features of Bickerstaff brainstem encephalitis (BBE) in children. Methods: In this retrospective study, data of 19 patients with BBE (11 males and 8 females) were collected from Department of Neurology, Beijing Children's Hospital from October 2015 to January 2018. The clinical features, treatment and prognosis were analyzed. Results: The onset age of BBE ranged from 1 year and 8 months to 12 years and 11 months. There were 18 cases with preceding infection. The most common infection was upper respiratory tract infection (9 cases), followed by simple fever (5 cases). The most common initial neurological symptoms were lethargy or disturbance of consciousness (8 cases), followed by limb weakness (5 cases). There were 6 cases of simple BBE and 13 cases of BBE overlapping Guillain-Barré syndrome (GBS). Besides the characteristic triad of altered mental status, ataxia, and ophthalmoplegia, there were other symptoms including convulsion (5 cases), diplopia (3 cases), nystagmus (7 cases), facial muscular weakness (7 cases),bulbar palsy (13 cases) and autonomic nerve symptoms (9 cases). Hypo or areflexia was seen in 16 cases. Positive Babinski's signs were seen in 8 cases. Hyponatremia was present in 10 cases in whom 4 showed severe hyponatremia. Albumin-cytological dissociation of cerebrospinal fluid was seen in 10 cases. The autoimmune antibodies were examined in all 19 patients. Anti-ganglioside antibodies including anti-GM1 IgG antibody was positive in 2 patients and one of whom was also found with positive anti-GD1b IgG antibody. Anti-GQ1b IgG antibody was present in 2 patients. Electromyography was performed in 14 cases and 8 cases, who were all BBE overlapping GBS, showed neurological damage. A total of 16 cases were monitored by video electroencephalography and 8 cases showed slow waves of background. In addition to, interictal focal discharge was detected in 2 cases. T2 fluid-attenuated inversion recovery (FLAIR) sequence abnormal signals were detected in 3 of 18 cases performed brain magnetic resonance imaging (MRI), and lesions involved with brainstem, basal ganglia, thalamus, cerebellum, corpus callosum and cerebral cortex. Lesions involved cervical and thoracic spinal cord were found in 1 out of 11 cases for whom spinal cord MRI was performed. All of the 4 cases who underwent enhanced MRI of spinal had partial nerve roots enhancement. All of the 19 patients received 1 to 2 courses of intravenous immunoglobulin therapy, and 2 cases also received plasma exchange. Fifteen cases received steroid therapy. The following-up period ranged from 3 months to 2.5 years. Two cases were lost to follow-up. Twelve cases achieved a full recovery within 3 months. Three cases recovered within 6 months. One case still had slight limb weakness and ataxia after 1 year and 8 months of follow-up, and another case had left autonomic nerve symptoms in the follow-up of 2 years and 3 months. Both of them were BBE overlapping GBS. Conclusions: Children's BBE is similar to that in adults, and is frequently found overlapped with GBS. Furthermore, it is sometimes accompanied by central nervous system demyelination disease. The antiganglioside antibodies are not often detectable. Immunoglobulin therapy could usually achieve good response. The prognosis of simple BBE is good in most situations. For BBE overlapping GBS, the more severe the limb weakness during the peak of disease is, the slower the recovery would be.