Abstract: Objective    To retrospectively study the level of lactate dehydrogenase（LDH）in cerebrospinal fluid（CSF），the pathogenic bacteria and the prognosis of children with purulent meningitis， and analyze the value of LDH level in predicting intracranial complications， in order to guide clinical diagnosis and treatment. Methods    The clinical data of 213 children aged 0-14 years，who were admitted to Children's Hospital，Zhejiang University School of Medicine between January 2016 and December 2018，were retrospectively analyzed.The children were categorized into different groups based on the type of pathogenic bacteria and recent incidence of intracranial complications. Subsequently，the differences in LDH levels in CSF among the groups were analyzed. The value of LDH in predicting intracranial complications was assessed using ROC curve analysis. Results    Out of the 213 children，90 had unknown pathogens and there were 123 tested positive for pathogen detection， including 59（48.0%）cases of Gram-positive（G +）bacteria and 64（52.0%）cases of Gram-negative（G-）bacteria.Among the children，122（57.3%）were successfully cured without any complications，while 91（42.7%）had complications， of whom 11（5.2%）died. The CSF-LDH level was significantly higher in children with intracranial complications than in those without complications （Z = -9.125， P<0.001）. The LDH level in the CSF was also statistically different in predicting the occurrence of intracranial complications （OR = 1.004， 95% CI 1.006-1.012， P<0.001）. The children in the death group had significantly higher LDH levels in their CSF compared to children with complications but survived （Z = -4.066， P<0.001）， with a significant difference in predicting the occurrence of death （OR = 1.002， 95% CI 1.001-1.004， P<0.001）. Furthermore， among children in the complication group， those aged ≥ 1 y had higher LDH level in their CSF compared to those aged <3 m and 3 m to <1 y （Z = -2.405， -2.927， P < 0.05， respectively）. There was no significant difference in LDH levels in the CSF between children with G+ bacterial infections and those with G- bacterial infections （Z = -1.805， P>0.05）. Receiver operating characteristic （ROC） curves were drown based on LDH， PRO， and GLU  concentrations in the CSF of children with or without complications during the acute phase， and the AUC values were 0.866， 0.790， and 0.742， respectively. LDH level showed higher predictive efficiency for intracranial complications compared to PRO and GLU （Z = 2.52 and 3.45， both P<0.05）， while PRO and GLU did not significantly differ in predictive efficiency （Z = 1.22， P>0.05）. Conclusion    The level of LDH in CSF of children with purulent meningitis at the early stage is related to the short-term prognosis.The higher the level，the higher the incidence of intracranial complications.

Key words: purulent meningitis, child, lactate dehydrogenase, complications

摘要： 目的    对化脓性脑膜炎患儿脑脊液中乳酸脱氢酶（LDH）水平和所感染病原菌及预后进行回顾性研究，分析LDH水平对预测颅内并发症的价值，以期指导临床诊治。方法    回顾性分析2016年1月至2018年12月浙江大学医学院附属儿童医院收治的213例0～14岁化脓性脑膜炎患儿临床资料。按患儿所感染病原菌及有无近期颅内并发症进行分组，分析各组患儿脑脊液中LDH差异，并用ROC曲线分析LDH对预测颅内并发症的价值。结果    213例中病原菌不明90例；病原菌检测阳性123例，其中革兰阳性（G+）菌59例（48.0%）、革兰阴性（G-）菌64例（52.0%）。治愈且无任何并发症122例（57.3%），有并发症91例（42.7%），其中死亡11例（5.2%）。有颅内并发症组脑脊液中LDH水平明显高于无并发症组（Z =-9.125，P<0.001），LDH水平对是否发生颅内并发症风险差异有统计学意义（OR = 1.004，95% CI 1.006～1.012，P<0.001）；死亡组脑脊液中LDH水平明显高于有并发症但存活组患儿（Z=-4.066，P<0.001），脑脊液LDH对死亡发生风险差异有统计学意义（OR=1.002，95% CI 1.001～1.004；P<0.001）；有并发症组中≥1岁组脑脊液LDH水平高于<3月龄组及3月龄至<1岁组（Z分别为-2.405、-2.927，P均<0.05）；G+菌感染组和G-菌感染组比较，两组脑脊液LDH差异无统计学意义（Z =-1.805，P>0.05）；根据有无并发症患儿急性期脑脊液中LDH、蛋白质、葡萄糖水平绘制ROC曲线，曲线下面积分别为0.866、0.790、0.742。LDH水平对颅内并发症的预测效能高于蛋白质和葡萄糖（Z值分别为 2.52和3.45，P 均<0.05），蛋白质与葡萄糖预测效能比较差异无统计学意义（Z=1.22，P>0.05）。结论    化脓性脑膜炎患儿病程早期脑脊液中LDH水平和近期预后相关，LDH越高合并颅内并发症发生风险越高。

关键词: 化脓性脑膜炎, 儿童, 乳酸脱氢酶, 并发症