[Clinical observation of 8 cases with central nervous system anaerobic infection diagnosed by metagenomic next-generation sequencing of cerebrospinal fluid].

The current study summarized the clinical characteristics of 8 patients with central nervous system anaerobic infections who visited the Second Hospital of Hebei Medical University from June 2019 to June 2021. Among the 8 patients, 7 cases had headache and fever as the first symptoms, and 1 case had left-sided limb weakness as the first symptom. Four patients had a previous history of diabetes (1 patient had a history of tooth extraction before the onset of the disease), 1 patient had a previous history of sinusitis, 1 patient had a history of tooth extraction before the onset of the disease, and 2 patients had chronic extensive periodontitis or periapical periodontitis. Five cases showed abnormal intracranial and/or meningeal enhancement on cranial magnetic resonance imaging (MRI), and 1 case showed swelling of the whole brain tissue on cranial computed tomography (CT). After treatment, symptoms of 4 cases were improved, symptoms of 1 case were aggravated, and 3 cases died. Anaerobic infections can occur in various parts of the body:the central nervous system, oral cavity, head and neck, chest, abdomen, pelvis, skin and soft tissues. It is generally believed that anaerobic bacteria rarely cause central nervous system infection, therefore, anaerobic culture of cerebrospinal fluid is usually not performed. Moreover, anaerobic culture is affected by many factors, and thus it is difficult to obtain positive results. Metagenomic next-generation sequencing can identify multiple pathogens (viral, bacterial, fungal, or parasitic) from samples based on DNA and/or RNA sequences and has advantages in diagnosing anaerobic infections of the central nervous system. Prompt empirical antimicrobial therapy is essential for the prognosis of the patients.