脑脊液糖/乳酸、脑脊液糖/血糖比值对颅内感染的诊断价值

Diagnostic value of ratio of cerebrospinal fluid sugar to lactic acid and ratio of cerebrospinal fluid sugar to blood glucose in patients with intracranial infection

目的:分析脑脊液糖/乳酸、脑脊液糖/血糖比值对颅内感染的诊断价值。方法:选择64例颅内感染患者(感染组)和56例神经系统非感染性疾病患者(对照组),入院24 h内采集外周静脉血和脑脊液标本,检测脑脊液乳酸、脑脊液糖、血糖、血WBC、脑脊液WBC,计算脑脊液糖/乳酸、脑脊液糖/血糖比值。结果:与对照组相比,感染组脑脊液糖水平及脑脊液糖/乳酸、脑脊液糖/血糖比值降低,脑脊液乳酸、血糖水平、血WBC、脑脊液WBC升高(P<0.05)。与病毒性感染、结核性感染相比,细菌性感染患者脑脊液糖水平、脑脊液糖/乳酸、脑脊液糖/血糖比值降低,脑脊液乳酸、血糖水平、血WBC、脑脊液WBC升高(P<0.05)。颅内感染患者脑脊液糖/乳酸、脑脊液糖/血糖比值与脑脊液WBC、血WBC呈负相关(r脑脊液WBC=-0.546、-0.512,r血WBC=-0.480、-0.427,P<0.05)。脑脊液糖/乳酸、脑脊液糖/血糖比值及脑脊液、血WBC均具有诊断颅内感染价值[ROC曲线下面积(95%CI)分别为0.882(0.801-0.963)、0.828(0.741-0.915)、0.763(0.709-0.817)、0.705(0.578-0.832.],脑脊液糖/乳酸、脑脊液糖/血糖比值诊断价值更高,其诊断界点分别为0.56、0.58,灵敏度分别为91.18%、88.24%,特异度分别为91.86%、94.19%。结论:颅内感染患者脑脊液糖/乳酸、脑脊液糖/血糖比值下降,细菌性颅内感染下降程度更明显,对颅内感染早期诊断有一定价值。

Aim:To analyze the changes of ratio of cerebrospinal fluid sugar to lactic acid and ratio of cerebrospinal fluid sugar to blood glucose of patients with intracranial infection and their diagnostic efficiencies.Methods:Sixty-four patients with intracranial infection(infection group)and 56 patients with non-infectious diseases of nervous system(control group)were selected.Peripheral venous blood and cerebrospinal fluid samples were collected within 24 hours after admission.The cerebrospinal fluid lactic acid,cerebrospinal fluid sugar,blood sugar,blood WBC and cerebrospinal fluid WBC were determined,and the ratio of cerebrospinal fluid sugar to lactic acid and ratio of cerebrospinal fluid sugar to blood glucose were calculated.Results:Compared with the control group,the level of cerebrospinal fluid sugar,the ratio of cerebrospinal fluid sugar to lactic acid and the ratio of cerebrospinal fluid sugar to blood glucose in the infection group were significantly lower,while the levels of cerebrospinal fluid lactic acid,blood glucose,blood WBC and cerebrospinal fluid WBC were significantly higher(P<0.05).Compared with the patients with viral and tuberculosis infections,the sugar level of cerebrospinal fluid,the ratio of cerebrospinal fluid sugar to lactic acid and the ratio of cerebrospinal fluid sugar to blood glucose were significantly lower in patients with bacterial infection,while the levels of cerebrospinal fluid lactic acid,blood sugar,blood WBC and cerebrospinal fluid WBC were significantly higher(P<0.05).The ratio of cerebrospinal fluid sugar to lactic acid and ratio of cerebrospinal fluid sugar to blood glucose of patients with intracranial infection were negatively correlated with cerebrospinal fluid WBC and blood WBC(r cerebrospinal fluid WBC=-0.546 and-0.512,r blood WBC=-0.480 and-0.427,P<0.05).The ratio of cerebrospinal fluid sugar to lactic,the ratio of cerebrospinal fluid sugar to blood glucose,cerebrospinal fluid WBC,and blood WBC was valuable in diagnosis of intracranial infection[the areas under the curve(95%CI)were 0.882(0.801-0.963),0.828(0.741-0.915),0.763(0.709-0.817),0.705(0.578-0.832.].The diagnostic value of the ratio of cerebrospinal fluid sugar to lactic acid and the ratio of cerebrospinal fluid sugar to blood glucose were higher with diagnostic cutoff value of 0.56 and 0.58,the sensitivity was 91.18%and 88.24%,respectively,and the specificity was 91.86%and 94.19%,respectively.Conclusion:The ratio of cerebrospinal fluid sugar to lactic acid and the ratio of cerebrospinal fluid sugar to blood sugar decrease in patients with intracranial infection,especially in bacterial intracranial infection,which have certain value for early diagnosis of intracranial infection.