Analysis Of Clinical Characteristics And Antibacterial Therapy Of Post-neurosurgical Intracranial Infection Due To Drug-resistant Acinetobacter Baumannii In NCU Patients

Objective:To provide basis for the prevention and antibacterial therapy of drug-resistant Acinetobacter baumannii postoperative intracranial infection(AbPII)through analyzing the clinical characteristics and antibacterial therapy in NCU patients diagnosed with drug-resistant AbPII,Methods:36 patients diagnosed with drug-resistant AbPII from the Department of Neuro Science Care Unit,Second Affiliated Hospital Zhejiang University School of Medicine during January 2014 and December 2018 were enrolled.The clinical characteristics of included patients were collected and summarized.Antibacterial effect was analyzed.Binary logistic regression was used to analyzing the independent factors influencing the prognosis of patients.Results:1. There were 86 PII patients,with 36 PII patients caused by drug-resistant Ab.Antibiotic susceptibility test suggested drug-resistant Ab was highly sensitive to polymyxin B(100%)and tigecycline(83%),but resistant to carbapenems(0%).2.36 patients with 21(58.33%)males fulfilled the inclusion criteria were enrolled.The average age was 51.77±14.90 and the average APACHE II score was 21.63±3.19.The main causes of surgical treatment were cerebral hemorrhage(52.78%)and traumatic brain injury(33.33%).26(72.22%)patients underwent craniotomy.28(77.78%)patients underwent emergency operation.20(55.56%)patients underwent multiple operations.26(72.22%)patients were placed with drainage device.There were 21(58.33%)patients with comorbidities and 35(97.22%)with coinfections.3.The period between first operation and PII were 6.61±2.91 days.All patients had fever,and 35 patients(97.22%)had decreased consciousness.The number of nucleated cells(2251.60±1681.25×10~6cells/L),the percentage of neutrophils(96.58±2.36%),the level of glucose(0.45±0.21 mmol/L)and protein(256.70±71.83 mg/dl)of cerebrospinal fluid test were far beyond the normal range.4.In the terms of antimicrobial therapy,6 patients were treated with monotherapy and 30 patients were treated with combined antibiotics therapy.Among the patients with combined antibiotics therapy,there were 5 patients with combination based on intravenous polymyxin B,13 patients with combination based on intravenous tigecycline,8 patients with combination based on intravenous plus intrathecal of polymyxin B,and 4 patients with intravenous plus intrathecal polymyxin B combined with intravenous tigecycline.As a result,16(44.44%)patients achieved clinical cure,The cure rate of combined antibiotics therapy was higher than monotherapy(P=0.024).The cure rate of intravenous plus intrathecal polymyxin B combined with intravenous tigecycline(100%)and the combination therapy based on intravenous plus intrathecal polymyxin B(75%)were relatively high.Multivariate regression analysis suggested that the treatment of intravenous plus intrathecal polymyxin B(OR=0.023 P=0.008)was an independent protective factor for prognosis.The levels of serum creatinine(P=0.001)and urea nitrogen(P=0.012)in patients treated with intravenous polymyxin B increased significantly after treatment.For patients with treatment failure,8 patients died in hospital and 12 patients died after giving up treatment due to poor prognosis.Conclusions:1.Ab is the most important gram-negative bacteria causing PII in NCU patients and highly sensitive to polymyxin B and tigecycline.2.Drug-resistant AbPII are more common in patients with cerebral hemorrhage and traumatic brain injury.Cerebrospinal fluid drainage,multiple operations,craniotomy,emergency operation,coinfection and comorbidity are important clinical features of drug-resistant AbPII patients.3.Drug-resistant AbPII always occur about 1 week after operation.Fever and decreased consciousness are the main clinical manifestations.Significant abnormality are found in cerebrospinal fluid test.4.The combined antibiotics therapy is more effective than monotherapy.The antibacterial effect of intravenous plus intrathecal polymyxin B combined with intravenous tigecycline and the combination therapy based on intravenous plus intrathecal polymyxin B are significant.The treatment of intravenous plus intrathecal polymyxin B may improve the prognosis of patients.The renal function should be closely monitored in the patients treated with intravenous polymyxin B.5.Drug-resistant AbPII has a great impact on the prognosis,and the mortality of patients with poor infection control is really high.The incidence of drug-resistant AbPII should be minimized as much as possible.