Faculty of Medicine, Universidad de Chile, Santiago, Chile.
Clinical Neurosciences, Royal Free London NHS Foundation Trust, London, United Kingdom.
Front Immunol. 2018 Nov 5;9:2568. doi: 10.3389/fimmu.2018.02568. eCollection 2018.
A 68-years-old Hispanic man, complained of night sweats, low grade fewer, unexplained weight loss, and memory problems over 3 months. Abdominal tomography showed multiple intra-abdominal adenopathy and biopsy confirmed classic Hodgkin's lymphoma. He commenced treatment with chemotherapy. Three months later, he had acute onset of inattention, auditory hallucinations and alterations of anterograde memory. The patient developed psychomotor agitation, unresponsive to a combination of neuroleptics and benzodiazepines. Brain MRI showed a small established cerebellar infarction. Electroencephalogram was normal. Tests for toxic metabolic encephalopathy were negative. One oligoclonal IgG bands was found in the Cerebrospinal fluid (CSF), which was not observed in corresponding serum, but cell count and protein were normal. Extensive testing for infectious encephalitis was unremarkable. CSF testing for commercially available neural and non-neural autoantibodies was negative. The patient fulfilled the Gultekin diagnostic criteria for paraneoplastic limbic encephalitis and methylprednisolone IV 1g/d for 5 days was given. He recovered rapidly, with progressive improvement in memory and psychomotor agitation. After treatment commenced, results for antibodies to mGluR5 in CSF taken prior to treatment were returned as positive. mGluR5 is found on post-synaptic terminals of neurons and microglia and is expressed primarily in the hippocampus and amygdala. This case highlights the difficulties in diagnosing this type of encephalitis: the CSF did not show pleocytosis, the MRI showed only chronic change and the electroencephalogram was normal. The dramatic recovery after methylprednisolone help to better characterized the clinical spectrum of auto-immune encephalitis. Diagnosing anti mGlutR5 encephalitis may lead to potentially highly effective treatment option and may anticipate the diagnostic of a cancer. A high index of suspicion is needed to avoid missed diagnosis. In patients with unexplained encephalitis, testing for antibodies to mGluR5 in CSF and serum should be considered. When there is a reasonable index of suspicion of auto-immune encephalitis, treatment should not be delayed for the antibody results.
一位 68 岁的西班牙裔男性，主诉夜间出汗、低热、不明原因体重减轻和记忆力问题，持续了 3 个月。腹部 CT 显示多个腹腔内淋巴结肿大，活检证实为经典霍奇金淋巴瘤。他开始接受化疗。3 个月后，他出现注意力不集中、幻听和顺行性记忆障碍。患者出现精神运动激越，对神经安定剂和苯二氮䓬类药物的联合治疗无反应。脑 MRI 显示小脑陈旧性小梗死。脑电图正常。毒代谢性脑病的检查结果均为阴性。在脑脊液 (CSF) 中发现了 1 条寡克隆 IgG 带，而相应的血清中则没有观察到，但细胞计数和蛋白均正常。广泛的传染性脑炎检查无明显异常。商业上可用的神经和非神经自身抗体的 CSF 检测均为阴性。患者符合副肿瘤性边缘叶脑炎的 Gultekin 诊断标准，给予静脉注射甲基强的松龙 1g/d，共 5 天。他迅速恢复，记忆和精神运动激越逐渐改善。治疗开始后，之前治疗前的 CSF 中抗 mGluR5 抗体的检测结果呈阳性。mGluR5 位于神经元和小胶质细胞的突触后末端，主要表达于海马体和杏仁核。该病例突出了诊断这种类型脑炎的困难：CSF 未显示细胞增多症，MRI 仅显示慢性改变，脑电图正常。甲基强的松龙治疗后的显著恢复有助于更好地描述自身免疫性脑炎的临床谱。诊断抗 mGluR5 脑炎可能会导致潜在的有效治疗选择，并可能预测癌症的诊断。需要高度怀疑以避免漏诊。对于原因不明的脑炎患者，应考虑检测 CSF 和血清中的抗 mGluR5 抗体。当有合理的自身免疫性脑炎怀疑指数时，不应因抗体结果而延迟治疗。
