Brainstem encephalitis: clinical analysis of 15 cases / 中华神经科杂志

ABSTRACT

Objective To investigate the clinical,neuroimaging, pathological features and prognosis of brainstem encephalitis. Methods The clinical and neuroimaging features and prognosis of 15 cases with brainstem encephalitis were analyzed retrospectively.Among them,1 case of brain autopsy was studied by HE,K-B and immunohistochemical staining. Results In 7 cases,the history of viral infections before the onset of disease was obtained.The initial neurological manifestation was dizzy in 6 cases,diplopia,headache and vomiting in 2 cases respectively,and unconciousness,ptosis and facial numbness in 1 case respectively.The main clinical features were shown that 15 cases demonstrated the involvement of cranial nerves,9 cases pyramidal tract and 5 cases spinothalamic tract,8 cases ataxia,4 cases Horner sign and 2 cases unconsciousness.MRI found single or multiple lesions in the corresponding parts of brainstem in 10 cases.In case of brain autopsy,neuropathological examination revealed local hemorrhagic necrotizing softening lesions in the pontine tegmentum and lateral medulla.A marked infiltration of lymphocytic inflammatory cells and macrophages were observed in the necrotic area.Myelin loss,axonal swelling and mild increase of reactive astrocytes were also observed in the cranial nerve nuclei.There was no positive finding of immunohistochemical staining by using the primary antibodies against HSV-I,Ⅱ,EB,CMV and toxoplasma.The prognosis for other surviving 14 cases were benign,and no relapsing case was found after 39.9 months of follow-up. Conclusions The course of brainstem encephalitis seems to be monophasic and benign,which indicates that it might be not the first episode of multiple sclerosis.The underlying causes of the disease are usually difficult to be identified.