Kotani Risa, Hatano Keiko, Ishibashi Kenji, Iwata Atsushi
Department of Neurology, Tokyo Metropolitan Institute for Geriatrics and Gerontology.
Research Team for Neuroimaging, Tokyo Metropolitan Institute for Geriatrics and Gerontology.
Rinsho Shinkeigaku. 2025 May 27;65(5):366-371. doi: 10.5692/clinicalneurol.cn-002082. Epub 2025 Apr 25.
This manuscript complements the clinical course of the first case of neurosyphilis in our previous report (Kotani. et al. Clin Nuc Med 2024) which highlighted the utility of F-THK5351 positron emission tomography (PET), a marker of astrogliosis, to visualize neuroinflammation. The patient was a right-handed man in his early 60s who presented with a three-month history of forgetfulness and subsequent right hemiparesis. Neurological and neuropsychological examinations revealed the right pyramidal signs and impairments in attention, memory, executive function, visuospatial cognition, and verbal fluency. The patient was diagnosed with neurosyphilis based on positive tests for syphilis antibodies in the serum and cerebrospinal fluid (CSF) and elevated CSF cell and protein levels. MRI revealed multiple infarcted lesions that explained the pyramidal signs; however, the lesions responsible for cognitive impairment were not visualized. Two months after penicillin G treatment, the patient exhibited partial improvements in cognitive function, without obvious changes in MRI. To investigate the underlying neuroinflammation associated with astrogliosis, we performed PET imaging after treatment. F-THK5351 PET revealed increased uptake and F-fluorodeoxyglucose (FDG) PET showed decreased uptake in the left deep frontal white matter and thalamus. We believed that the right pyramidal signs were associated with infarctions contributed by meningovascular syphilis in addition to the arteriosclerosis, whereas cognitive impairment was associated with neuroinflammation due to parenchymal syphilis. Furthermore, the impairment of thalamocortical circuits may have compromised the widespread cortical excitability underlying cognitive impairments. This report highlights the utility of F-THK5351 PET imaging in understanding the pathogenesis of neurosyphilis, including cognitive impairment. Further longitudinal studies are required to elucidate the relationship between neuroinflammation and the clinical presentation of neurosyphilis.
本手稿补充了我们之前报告（Kotani等人，《临床核医学》2024年）中首例神经梅毒病例的临床病程，该报告强调了作为星形胶质细胞增生标志物的F-THK5351正电子发射断层扫描（PET）在可视化神经炎症方面的效用。患者是一名60岁出头的右利手男性，有三个月的健忘病史，随后出现右侧偏瘫。神经学和神经心理学检查发现右侧锥体束征以及注意力、记忆力、执行功能、视觉空间认知和语言流畅性受损。根据血清和脑脊液（CSF）中梅毒抗体检测呈阳性以及CSF细胞和蛋白质水平升高，该患者被诊断为神经梅毒。MRI显示多个梗死灶，解释了锥体束征；然而，导致认知障碍的病灶未显示出来。青霉素G治疗两个月后，患者认知功能有部分改善，MRI无明显变化。为了研究与星形胶质细胞增生相关的潜在神经炎症，我们在治疗后进行了PET成像。F-THK5351 PET显示左侧额叶深部白质和丘脑摄取增加，而F-氟脱氧葡萄糖（FDG）PET显示摄取减少。我们认为，右侧锥体束征除了与动脉硬化有关外，还与脑膜血管梅毒导致的梗死有关，而认知障碍与实质梅毒引起的神经炎症有关。此外，丘脑皮质回路的损害可能损害了认知障碍背后广泛的皮质兴奋性。本报告强调了F-THK5351 PET成像在理解神经梅毒发病机制（包括认知障碍）方面的效用。需要进一步开展纵向研究以阐明神经炎症与神经梅毒临床表现之间的关系。
