Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Campus Virchow Klinikum, Berlin, Germany.
Crit Care. 2009;13(1):R2. doi: 10.1186/cc7689. Epub 2009 Jan 20.
Bacterial meningitis (BM) is a severe complication in patients with aneurysmal subarachnoid haemorrhage (SAH). Clinical signs of meningitis are often masked by SAH-related symptoms, and routine cerebrospinal fluid (CSF) analysis fails to indicate BM. Microdialysis (MD) is a technique for monitoring cerebral metabolism in patients with SAH. A cohort study was performed to investigate the value of MD for the diagnosis of BM.
Retrospectively, 167 patients with SAH in an ongoing investigation on cerebral metabolism monitored by MD were analysed for the presence of BM and related MD changes. Diagnosis of BM was based on microbiological CSF culture or clinical symptoms responding to antibiotic treatment, combined with an increased CSF cell count and/or fever. Levels of MD parameters before and after diagnosis of BM were analysed and compared with the spontaneous course in controls.
BM developed in 20 patients, of which 12 underwent MD monitoring at the time of diagnosis. A control group was formed using 147 patients with SAH not developing meningitis. On the day BM was diagnosed, cerebral glucose was lower compared with the value three days before (p = 0.012), and the extent of decrease was significantly higher than in controls (p = 0.044). A decrease in cerebral glucose by 1 mmol/L combined with the presence of fever >or= 38 degrees C indicated BM with a sensitivity of 69% and a specificity of 80%. CSF chemistry failed to indicate BM, but the cell count increased during the days before diagnosis (p < 0.05).
A decrease in MD glucose combined with the presence of fever detected BM with acceptable sensitivity and specificity, while CSF chemistry failed to indicate BM. In patients with SAH where CSF cell count is not available or helpful, MD might serve as an adjunct criterion for early diagnosis of BM.
细菌性脑膜炎（BM）是动脉瘤性蛛网膜下腔出血（SAH）患者的严重并发症。脑膜炎的临床症状常被 SAH 相关症状所掩盖，常规脑脊液（CSF）分析无法提示 BM。微透析（MD）是监测 SAH 患者脑代谢的一种技术。进行了一项队列研究，以探讨 MD 对 BM 的诊断价值。
回顾性分析了正在进行的 MD 监测脑代谢的 167 例 SAH 患者，以评估 BM 的存在及其相关 MD 变化。BM 的诊断基于微生物 CSF 培养或对抗生素治疗有反应的临床症状，同时伴有 CSF 细胞计数增加和/或发热。分析了 BM 诊断前后 MD 参数的水平，并与对照组的自发病程进行比较。
20 例患者发生 BM，其中 12 例在诊断时接受了 MD 监测。使用未发生脑膜炎的 147 例 SAH 患者形成对照组。在 BM 诊断当天，脑葡萄糖水平较前三天（p = 0.012）下降，下降幅度明显高于对照组（p = 0.044）。脑葡萄糖下降 1mmol/L 合并发热>或=38 度可提示 BM，敏感性为 69%，特异性为 80%。CSF 化学未能提示 BM，但在诊断前几天细胞计数增加（p < 0.05）。
MD 葡萄糖下降合并发热可提示 BM，具有可接受的敏感性和特异性，而 CSF 化学未能提示 BM。在 CSF 细胞计数不可用或无帮助的 SAH 患者中，MD 可能作为早期诊断 BM 的附加标准。
