Streptococcus intermedius is a member of the S. anginosus group and is part of the normal oral microbiota. It can cause pyogenic infections in various organs, primarily in the head and neck area, including brain abscesses and meningitis. However, ventriculitis due to periodontitis has not been reported previously. A 64-year-old male was admitted to the hospital with a headache, fever and later imbalance, blurred vision, and general slowness. Neurological examination revealed nuchal rigidity and general clumsiness. Meningitis was suspected, and the patient was treated with dexamethasone, ceftriaxone and acyclovir. A brain computer tomography (CT) scan was normal, and cerebrospinal fluid (CSF) Gram staining and bacterial cultures remained negative, so the antibacterial treatment was discontinued. Nine days after admission, the patient’s condition deteriorated. The antibacterial treatment was restarted, and a brain magnetic resonance imaging revealed ventriculitis. A subsequent CT scan showed hydrocephalus, so a ventriculostomy was performed. In CSF Gram staining, chains of gram-positive cocci were observed. Bacterial cultures remained negative, but a bacterial PCR detected Streptococcus intermedius. An orthopantomography revealed advanced periodontal destruction in several teeth and periapical abscesses, which were subsequently operated on. The patient was discharged in good condition after one month. Poor dental health can lead to life-threatening infections in the central nervous system, even in a completely healthy individual. Primary bacterial ventriculitis is a diagnostic challenge, which may result in delayed treatment and increased mortality.

中文翻译：

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中间链球菌引起严重牙周炎患者原发性细菌性脑室炎——病例报告

中间链球菌是咽峡炎链球菌群的成员，也是正常口腔微生物群的一部分。它可引起各种器官的化脓性感染，主要是头颈部区域，包括脑脓肿和脑膜炎。然而，牙周炎引起的脑室炎此前尚未见报道。一名 64 岁男性因头痛、发烧、后来身体不平衡、视力模糊、行动迟缓入院。神经系统检查显示颈部僵硬和普遍笨拙。怀疑患有脑膜炎，患者接受了地塞米松、头孢曲松和阿昔洛韦治疗。脑部计算机断层扫描（CT）扫描正常，脑脊液（CSF）革兰氏染色和细菌培养仍呈阴性，因此停止抗菌治疗。入院九天后，患者病情恶化。重新开始抗菌治疗，脑部磁共振成像显示脑室炎。随后的 CT 扫描显示脑积水，因此进行了脑室造口术。在脑脊液革兰氏染色中，观察到革兰氏阳性球菌链。细菌培养仍呈阴性，但细菌 PCR 检测到中间链球菌。正畸断层扫描显示几颗牙齿有严重的牙周破坏和根尖周脓肿，随后进行了手术。 1个月后，患者康复出院，情况良好。即使对于完全健康的人来说，牙齿健康状况不佳也会导致中枢神经系统出现危及生命的感染。原发性细菌性脑室炎是一个诊断挑战，可能导致治疗延迟和死亡率增加。