Clinical characteristics and elevated ProGRP and positive oligoclonal bands of 13 Chinese cases with anti‐GABABR encephalitis

Abstract

Objective To improve the clinical understanding of anti‐gamma‐aminobutyric‐acid B receptor encephalitis (anti‐GABABR encephalitis) by analyzing 13 cases. Methods We retrospectively studied demographic and clinical features including clinical symptoms, serum/cerebrospinal fluid (CSF) laboratory findings (including antibody test), brain magnetic resonance imaging (MRI), electroencephalogram (EEG), treatment plan, and treatment effect for 13 patients with a definitive diagnosis of anti‐GABABR encephalitis. Results Seven patients (53.8%, 7/13) were complicated with lung cancer. Epileptic seizures were the most common symptoms at onset in 11 patients (84.6%, 11/13). All patients had seizures in the course of the disease. Abnormalities in craniocerebral MRI examination, including hippocampus, occipital lobe, insular lobe, were found in six of nine tested patients, and EEG abnormalities were found in seven out of nine tested patients. Elevated pro‐gastrin releasing peptide (ProGRP) levels were found in 70% of patients with a median value of 490.10 pg/ml; and CSF oligoclonal bands were positive for 4 of 10 tested cases. However, there were no significant differences in modified Rankin Scale (mRS) between the ProGRP or CSF oligoclonal band positive and negative groups at admission and follow‐up (p > .05). The value between SCLC and non‐SCLC subgroup was significantly different (p < .05). Ten patients received immunotherapy (three patients refused treatment). After immunotherapy, the frequency of seizures was significantly reduced. There was a significant difference in mRS between admission and after treatment (p < .05). The average survival time after onset was 27.7 months. Conclusions Epilepsy is the most common clinical manifestation of Anti‐GABABR encephalitis. The prognosis of anti‐GABABR encephalitis is poor. Section of anti‐GABABR encephalitis patients have higher level of serum ProGRP and positive GSF oligoclonal bands. Elevated ProGRP or positive CSF oligoclonal bands with classic clinical features can potentially help to improve early recognition of anti‐GABABR encephalitis.

A Prognostic Analysis of the Outcomes in Patients With Anti-γ-Aminobutyric Acid B Receptor Encephalitis

“…Here, we showed a tumor rate of 36% with the vast majority of the neoplastic cases being SCLC, which is similar to the prevalence (33.3%-38.7%) of tumors in two studies in China ( 10 , 12 ). However, as in other previous studies, approximately 50% of cases have an associated tumor ( 3 , 8 , 14 , 15 ). We cannot exclude the possibility that tumors were detected after discharge in the four patients who were lost to follow-up.…”

“…Therefore, if the patient shows GABA B R antibody along with other onconeuronal antibodies, SCLC should be considered until proven otherwise. In another study, level of serum pro-gastrin releasing peptide (ProGRP) was higher in anti-GABA B R encephalitis patients than in normal population, and the level of serum ProGRP showed significant difference between SCLC and non-SCLC subgroup ( 15 ). It is a pity that proGRP was not a routine test in our study.…”

Clinical characteristics and prognosis of anti-γ-aminobutyric acid-B receptor encephalitis: A single-center, longitudinal study in China

“…Anti-GABA B R encephalitis usually starts with epilepsy. Consistent with this, the most prominent features in the early stage are various types of epileptic seizures and neuropsychiatric symptoms ( 2 – 7 , 9 , 10 , 12 ). The latter mostly manifest as personality changes (anxiety, depression, mania), loss of memory for recent events, behavioral abnormalities, disorders of consciousness, and sleep disorders ( 1 – 3 , 5 – 7 , 9 , 10 ).…”

“…More than half of patients with anti-GABA B R encephalitis have concurrent tumors, most of which are SCLC ( 2 – 7 , 9 , 12 – 15 ), other associated tumors include thymoma ( 25 ), esophageal cancer ( 1 ), and melanoma ( 23 ), and so on. While only 40/114 (36%) of patients in an Asian series had tumors ( 13 , 16 ).…”

“…Eighteen of our patients (48.6%) were diagnosed with lung cancer, comprising one large-cell neuroendocrine carcinoma of the lung and 17 SCLC. The low prevalence of tumors in some Chinese studies may be attributable to more youthful enrolled cases, small series, insufficient screening for tumors, and relatively short follow-up times ( 12 ).…”