Clinical characteristics and prognosis of anti-GABA(B)R encephalitis: A single-center experience

The purpose of this study was to assess the demographic data, clinical manifestations, cerebrospinal fluid (CSF), hematology, brain magnetic resonance imaging, electroencephalograms, and therapy and prognosis related to anti-gamma-aminobutyric acid B (anti-GABA(B)R) encephalitis. We retrospectively examined the demographic data, clinical manifestations, laboratory results, brain magnetic resonance imaging, electroencephalograms, and therapy and prognosis of 6 patients with anti-GABA(B)R encephalitis. We used the clinical data of patients with anti-GABA(B)R encephalitis admitted to the Department of Neurology of Mianyang Central Hospital obtained from January 2017 to September 2020. Six patients with anti-GABA(B)R encephalitis were included. Generalized tonic-clonic seizure was the first clinical symptom in 5 patients, while 1 patient first showed behavior disorder. After the first clinical symptom attack, 2 patients developed a memory deficit, 4 cases showed cognitive decline, 3 cases showed behavior disorder, 1 patient developed status epilepticus and only 1 patient returned to normal. CSF testing indicated normal intracranial pressure in 5 patients and elevated pressure in only 1 patient. Additionally, the cerebrospinal fluid tests revealed slight leukocytosis in all patients and elevated protein levels in 5 patients. The anti-GABA(B)R antibody was positive in both serum and CSF in all patients. Brain magnetic resonance imaging showed limbic system lesions in 4 patients. Long-term electroencephalograms revealed abnormal waves in half of the patients. All patients were treated with high dosages of methylprednisolone, which was combined with intravenous immunoglobulin in 2 patients; symptoms were improved in 4 patients, 1 patient showed no significant change and 1 patient with status epilepticus died of severe pneumonia during hospitalization. Epilepsy is the most common initial symptom in patients of anti-GABA(B)R encephalitis. Many patients are also affected by tumors. Early immunotherapy can achieve excellent effects, the long-term prognosis is good for most patients.