Anaerobic meningitis is a rare serious clinical condition which mainly affects vulnerable populations and patients with predisposing factors such as head trauma, prior neurosurgical procedures or implantable medical devices such as ventriculoperitoneal shunts or ventricular drains. In this study we retrieved data from aerobic and anaerobic cultures of cerebrospinal (CSF) or ventricular fluid ordered over a 5 year period at our institution. A total of 8868 aerobic and 594 anaerobic cultures were performed from 2013 to 2017. 24/594 (4%) anaerobic cultures from 14 patients were positive for anaerobes. Only 3 of those patients were diagnosed clinically with anaerobic meningitis, each with predisposing factors, while anaerobes (Cutibacterium acnes and Clostridium perfringens) recovered from the remaining 21 patients were regarded as contaminants. 129/8868 (1.45%) aerobic CSF cultures were positive for anaerobes. 120/129 (93%) cultures recovered C. acnes while non-C. acnes anaerobes were recovered in the remaining 9 cultures and were deemed to be contaminants. In the majority of situations, recovery of C. acnes from CSF or ventricular fluid was regarded as contamination. Our cohort included 18 patients with a ventriculoperitoneal shunt or ventricular drain, 17 of whom had C. acnes recovered from either aerobic or anaerobic culture, and 10 were treated with targeted antibiotics and surgical replacement of the shunt or drain. Anaerobic culture of the CSF or ventricular fluid aided in identification of two patients with anaerobic meningitis and an additional two patients with shunt infection. Anaerobe culture of CSF is important in identification of anaerobic meningitis, as growth of anaerobes other than C. acnes is rare from aerobic CSF culture.

无氧脑膜炎是一种罕见的严重临床疾病，主要影响易感人群和易感因素，例如头部外伤，先前的神经外科手术程序或可植入的医疗设备，例如心室腹膜分流或心室引流。在这项研究中，我们从有氧和无氧的脑脊液（CSF）或心室积液中抽取了数据，这些数据在我们机构订购了5年。从2013年到2017年，总共进行了8688次有氧和594次厌氧培养。来自14例患者的24/594（4％）厌氧培养呈厌氧菌阳性。这些患者中只有3例在临床上被诊断为厌氧性脑膜炎，每个患者都有诱发因素，而厌氧菌（痤疮杆菌和产气荚膜梭状芽胞杆菌从其余21例患者中恢复的被视为污染物。129/8868（1.45％）有氧脑脊液培养的厌氧菌呈阳性。120/129（93％）培养物回收了痤疮丙酸杆菌，而其余9种培养物中均回收了非痤疮丙酸杆菌厌氧菌，被认为是污染物。在大多数情况下，从CSF或心室液中回收痤疮丙酸杆菌被视为污染。我们的研究对象包括18例脑室腹膜分流或心室引流的患者，其中17例患有痤疮丙酸杆菌可从有氧或无氧培养物中回收，并用靶向抗生素和分流或引流的手术替代治疗10例。脑脊液或心室液体的厌氧培养有助于鉴定两名厌氧性脑膜炎患者和另外两名分流感染患者。CSF的厌氧菌培养物对于厌氧性脑膜炎的鉴别很重要，因为好氧CSF培养物中很少有痤疮丙酸杆菌以外的厌氧菌的生长。