颅脑术后继发颅内感染细菌革兰染色特征的临床意义

The significance of clinical indicators of different Gram-stained bacteria resulted in secondary intracranial infection after craniocerebral operation

目的比较分析颅脑术后不同革兰染色细菌引起的中枢神经系统感染的临床特征与其他感染检验参数的差异，为早期抗感染治疗提供依据，减少超广谱抗菌药的使用及耐药菌株的产生。方法采取单中心回顾性研究，调查2012年1月至2016年12月解放军总医院颅脑手术后诊断为颅内感染的病历资料，分析病例的一般情况、临床特征、实验室检查结果、抗感染疗程及预后。结果5年期间颅脑手术后继发颅内感染813例，发病率为5．43％（813／14986），脑脊髓液培养阳性率9．72％（79／813），根据诊断标准，纳入本研究的病例数量为71例，其中46例检出革兰阳性菌（G＋菌组），占64．8％（46／71），25例检出革兰阴性菌（G-菌组），占35．2％（25／71）。G＋菌组的发病距离手术时间及抗感染疗程分别为5．0（4．0，6．0）d、（18．3±6．8）d，均短于G-菌组的9．0（7．0，11．0）d、（29．2±9．9）d，差异均有统计学意义（Z=-6．184、t=-5．245，均P〈0．01）。G＋菌组的血清降钙素原浓度为1．02（0．83，1．27）μg／L，低于G-菌组的2．68（1．97，5．07）μg／L，差异有统计学意义（Z=-5．719，P〈0．01）；脑脊髓液葡萄糖含量为（2．13±1．30）mmol／L，高于G-菌组的（1．09±0．95）mmol／L，差异有统计学意义（t=3．512，P〈0．01）；蛋白含量为（1615．93±848．83）mg／L，低于G-菌组的（2480．60±1105．28）mg／L，差异有统计学意义（t=-3．679，P〈0．01）；两组的血清C-反应蛋白浓度分别为（96．2±46．1）、（117．8±46．3）mg／L，差异无统计学意义（t=-1，884，P〉0．05）。G-菌感染组死亡率为16．0％（4／25），G＋菌感染组无死亡病例。结论G＋菌与G-菌引起的颅脑术后颅内感染的发病时间、血清降钙素原浓度、脑脊髓液葡萄糖与蛋白的含量有明显差异。在未获得病原学报告时可根据这些指标，指导早期经验性抗感染治疗的药物选择。

Objective To compare and analyze the clinical characteristics and laboratory parameters of central nervous system （CNS） infection caused by different Gram-stained bacteria after craniocerebral surgery, and to provide a preliminary basis for early anti-infection treatment to reduce the use of extended-spectrum antibiotics and the generation of resistant strains. Methods A single center retrospective study was conducted to investigate the clinical data of patients with intracranial infection after craniocerebral surgery from January 2012 to December 2016 in PLA general hospital. The general conditions, clinical features, laboratory parameters, antibiotic treatments and prognosis were analyzed. Results A toal of 813 cases of CNS infection after eraniocerebral surgery were found during the 5-year period, with an incidence rate of 5.43% （813/14 986）. The positive rate of cerebrospinal fluid （CSF）culture was 9. 72% （79/ 813 ）. According to the criteria, 71 cases were included in the study. Among all the cases ,64. 8% （46/71） of which were Gram-positive bacteria （ G＋ ） and 35. 2% （25/71） were identified as Gram-negative bacteria （ G- ）. The duration between surgery and meningitis events, as well as the period of antibiotic treatment for G＋ bacteria group were 5.0 （4. 0, 6. 0） days and （ 18.3 ± 6. 8 ） days, which were shorter than those of the G- bacteria group 9.0 （7.0, 11.0） days and （29. 2 ± 9. 9） days （Z = - 6. 184, t = - 5. 245, both P 〈 0. 01 ） , and the differences were statistically significant. The serum procalcitonin concentration in the G＋ group was lower than that in G- group [ 1.02 （0. 83,1.27 ） μg/L vs 2. 68 （ 1.97,5.07 ） μg/L, Z = -5.719, P 〈 0. 01 ）. The cerebrospinal fluid glucose content was higher than that of G- bacteria group [ （2. 13 ± 1.30） mmol/L vs （ 1.09 ±0. 95） mmol/L, t =3. 512, P 〈0. 01 ]. The protein level was lower than that of G- bacteria group [（1 615.93 ±848.83） mg/L vs （2 480. 60 ±1 105.28） mg/L, t= -3.679, P〈 0. 01 ]. Serum C-reactive protein concentrations in the two groups did not show any statistical significance [ （96. 2 ± 46. 1 ） mg/L vs （ 117.8 ± 46. 3 ） mg/L, t = - 1. 884, P 〉 0. 05 ]. In addition, the mortality rate of the G- bacteria group was 16. 0% （4/25）, and 0 in G＋ bacteria group. Conclusion The time of onset of intracranial infection, serum PCT concentration, and cerebrospinal fluid glucose and protein content caused by Gram-positive bacteria and Gram-negative bacteria are found to be significantly different, and these findings could serve as a preliminary guide for the selection of antibiotics in early experiential anti-infective treatments without the etiology report.