ObjectiveTo study the clinical distribution and the change of drug resistance of Acinetobacter baumannii from different inpatient specimens sources during 2008 to 2012, and to provide guidance for rational use of antibiotics. MethodsThe identification of Acinetobacter baumannii was conducted by VITEK-2 based on clinical and laboratory standards institute (CLSI) guideline between January 2008 and December 2012. The susceptibility of antibiotics was determined by K-B test, and data analysis was conducted by Excel and SAS. ResultsA total of 3 139 stains of Acinetobacter baumannii were isolated from 2013 patients during this period. The Acinetobacter baumannii was mainly obtained from the Burn ward, Intensive Care Unit ward and Thoracic ward. Sputum was the most specimens of Acinetobacter baumannii, accounting for 48.4%. The drug resistance rates of Acinetobacter baumannii to most of the antimicrobial agents were more than 55%. Compound antibacterial is more effective than the single drug ingredient. Compared with other antimicrobial agents, β-lactams/β-lactamase inhibitor compound and carbapenems antimicrobial agents were more sensitive. ConclusionThe drug resistance of Acinetobacter baumannii is serious and has differences among hospitals. Clinicians should monitor the drug resistance of Acinetobacter baumannii timely and choose proper antibiotics according to the results of drug sensitivity.
There is a worldwide consensus that urgent action is needed to prevent and control multi-drug resistant organisms in health care settings, especially carbapenem-resistant Enterobacteriaceae (CRE), carbapenem-resistant Acinetobacter baumannii (CRAB) and carbapenem-resistant Pseudomonas aeruginosa (CRPsA). In 2017, to focus on this topic, World Health Organization organized experts worldwide to develop guidelines for the prevention and control of CRE, CRPsA and CRAB. In this paper, we introduced the background, development process, main measures, advantages and disadvantages of the guidelines to help infection prevention and control practitioners take actions properly based on the guidelines.
ObjectiveTo explore the infection condition of Acinetobacter baumannii at the Neurosurgery Intensive Care Unit (NICU), and analyze the possible risk factors. MethodsWe retrospectively analyzed the clinical data of Acinetobacter baumannii infection patients with craniocerebral injury treated at the NICU between January 2011 and June 2013. We collected such information as infection patients' population distribution, infection site, invasive operations and patients' nurse-in-charge level and so on, and analyzed the possible risk factors for the infection. ResultsThirty-one patients were infected with Acinetobacter baumannii, and they were mainly distributed between 60 and 80 years old. The main infection site was lower respiratory tract, followed in order by urinary tract, gastrointestinal tract, skin and soft tissue. The risk factors might be related to age, invasive operation, nurse working ability, etc. ConclusionThe patients at the NICU are vulnerable to infection of Acinetobacter baumannii. Reducing invasive diagnosis and nursing procedures, providing optimal care, and carrying out specialized nurse standardization training may be the important means to effectively reduce the infection.
ObjectiveTo evaluate the diagnostic value of soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) level in bronchoalveolar lavage fluid (BALF) for discrimination of Acinetobacter baumannii (A. baumannii) colonization from infection.MethodsSixty patients with tracheal intubation or tracheotomy who were admitted in intensive care unit from July 2016 to July 2018, were divided into an infection group (n=20), a colonization group (n=20) and a control group (n=20). The serum and BALF samples were collected from the patients on the day when lower respiratory tract sample culture was positive so as to detect sTREM-1, serum procalcitonin (PCT) and interleukin-6 (IL-6). The value of serum PCT, IL-6, sTREM-1 and BALF sTREM-1 in differentiation of infection or colonization for A. baumannii was analyzed by mean of receiver operating characteristic (ROC) curve.ResultsThere were no significant differences in gender composition, age or Glasgow coma score among the three groups (P>0.05). The clinical pulmonary infection score (CPIS) of the infection group was higher than that in the control group (P<0.05). Compared with the control group, while the sTREM-1 concentration of BALF with A. baumannii colonization increased significantly but levels of PCT, IL-6 and sTREM-1 remained unchanged in serum. The levels of PCT, IL-6 and sTREM-1 in serum, and sTREM-1 in BALF increased significantly in the infection group (P<0.001). Compared with the colonization group, the levels of PCT, IL-6 and sTREM-1 in serum, and sTREM-1 in BALF increased significantly in the infection group (P<0.05). The area under the ROC curve (AUC) of serum PCT was 0.67 with the sensitivity of 0.55 and the specificity of 0.90 (95%CI 0.52 - 0.82). AUC of serum IL-6 was 0.72 with the sensitivity of 0.60 and the specificity of 0.95 (95%CI 0.58 - 0.85). AUC of serum sTREM-1 was 0.72 with the sensitivity of 0.75 and the specificity of 0.60 (95%CI 0.55 - 0.85). AUC of sTREM-1 in BALF was 0.92 with the sensitivity of 0.95 and the specificity of 0.70 (95%CI 0.79 - 0.98). The diagnostic accuracy of sTREM-1 in BALF was higher than that of PCT, IL-6 and sTREM-1 in serum (P<0.05).ConclusionssTREM-1 in BALF has good diagnostic performance in differentiating patients with infection of colonization for A. baumannii. Its sensitivity and specificity are higher than serum PCT, IL-6 and sTREM-1.
Objective To evaluate the clinical effects and safety of polymyxin B on ventilator-associated pneumonia caused by pandrug-resistant Acinetobacter baumannii (PDR-AB) in patients with chronic obstructive pulmonary disease (COPD). Methods COPD patients who were diagnosed as ventilator-associated pneumonia caused by PDR-AB and treated with polymyxin B between January 2015 and August 2016 in this hospital were included in this retrospective study. The patients’ symptoms, vital signs, and the results of laboratory examinations were recorded before and after treatment. The clinical cure rates, microbiological eradication rates, mortality and safety were also measured. Results A total of 11 cases were included in this study. Mean time of therapy was 10 days, ranged 8-13 days. After treatment with polymyxin B, most of the patients’ clinical symptoms, signs, and results of laboratory tests as well as imaging examinations were significantly improved. Seven cases had clinical response, and the clinical efficacy rate was 63.6%; 8 cases achieved bacteriological eradication, with the bacteriological eradication rate of 72.7%. Four patients died, and the overall mortality was 36.4%. Only 1 case discontinued treatment with polymyxin B because of the drug fever. Conclusions Polymyxin B might be an alternative option for COPD patients with ventilator-associated pneumonia caused by PDR-AB, who is non-responder to prior antimicrobial therapy. However, this method should be evaluated cautiously in prospective well-controlled studies.
Objective To investigate the predictors for carbapenem-resistant Acinetobacter baumannii, Enterobacteriaceae and Pseudomonas aeruginosa (CR-AEP) as the pathogens of bloodstream infection (BSI) for intensive care unit (ICU) patients. Methods A retrospective case-control study based on ICU- healthcare-associated infection (HAI) research database was carried out. The patients who have been admitted to the central ICU between 2015 and 2019 in the ICU-HAI research database of West China Hospital of Sichuan University were selected. The included patients were divided into two groups, of which the patients with ICU-acquired BSI due to CR-AEP were the case group and the patients with BSI due to the pathogens other than CR-AEP were the control group. The clinical features of the two groups of patients were compared. Logistic regression model was used to identify the predictors of BSI due to CR-AEP.ResultsA total of 197 patients with BSI were included, including 83 cases in the case group and 114 cases in the control group. A total of 214 strains of pathogenic bacteria were isolated from the 197 BSI cases, including 86 CR-AEP strains. The results of multivariate logistic regression analysis showed that previous use of tigecycline [odds ratio (OR)=2.490, 95% confidence interval (CI) (1.141, 5.436), P=0.022] was associated with higher possibility for CR-AEP as the pathogens of BSI in ICU patients with BSI, while previous use of antipseudomonal penicillin [OR=0.497, 95%CI (0.256, 0.964), P=0.039] was associated with lower possibility for that. Conclusion Previous use of tigecycline or antipseudomonal penicillin is the predictor for CR-AEP as the pathogens of BSI in ICU patients with BSI.
Intracranial Acinetobacter baumannii infection is a rare clinical disease with a gradual increase in incidence and extremely high mortality. With the continuous enhancement of bacterial resistance, more and more intracranial infections of multidrug-resistant and extensively drug-resistant Acinetobacter baumannii have appeared in the clinic, and its treatment has become a major challenge and problem faced by neurosurgeons. The treatment difficulties include the selection, usage and dosage of antimicrobial agents, as well as whether cerebrospinal fluid drainage is needed. A standardized treatment plan is still needed. In this paper, combining domestic and foreign literature, the treatment of intracranial infection of multidrug-resistant and extensively drug-resistant Acinetobacter baumannii will be reviewed in order to provide a reference for clinical treatment.
Objective To study the risk factors and prognosis of hospital acquired pneumonia( HAP)caused by carbapenem-resistant Acinetobacter baumannii( CRAB) . Methods By a case-control study, the data of 44 cases of HAP caused by CRAB fromJan 2005 to Dec 2007 in Nanfang Hospital were analyzed. 66 cases of HAP caused by Carbapenem-susceptible A. baumannii ( CSAB) were selected randomly at the same time as control. Univariate analysis( T test and chi-square test) and multivariate logistic regression were used for statistics analysis. Results Univariate analysis revealed that five factors associated with the infection caused by CRAB were APACHE Ⅱ score ≥ 16, chronic pulmonary disease ( COPD/ bronchiectasis ) , imipenem/meropenem and fluoroquinolone used 15 days before isolation of CRAB, and early combination therapy of antibiotics. Multivariate logistic regression analysis identified two independent factors as APACHEⅡ score ≥16( OR=6. 41, 95% CI 2. 20-18. 67) and imipenem/meropenemused 15 days before isolation of CRAB( OR =6. 33,95% CI 1. 83-21. 87) . Of 44 cases of CRAB infections, 14 patients died and 30 patients survived. Univariate analysis revealed that two factors associated with poor prognosis were organ failure and clinical pulmonary infection score( CPIS) rise after three-day treatment. According to multivariate logistic regression analysis, only CPIS rise after three-day treatment ( OR =7. 01, 95% CI 1. 23-40. 03) was an independent predictive factor. Conclusions APACHEⅡ score ≥ 16 and imipenem/meropenem used 15 days before isolation of CRAB were independent risk factors for CRAB infection. CPIS rise after three-day treatment was a predictive factor for the prognosis of CRAB infection.
ObjectiveTo detect the in vitro susceptibility of common clinical multidrug-resistant bacteria to tigecycline by disk diffusion (KB), minimum inhibitory concentrations (MIC) test strip (MTS) and Vitek 2 Compact methods, in order to evaluate the accuracy of the three different susceptibility testing methods. MethodsA total of 140 multidrug-resistant isolates (excluding Pseudomonas aeruginosa) were collected retrospectively from West China Hospital between January 2014 and March 2015. The inhibitory zone diameters and MIC of tigecycline were determined by KB, Vitek 2 Compact system and MTS respectively. The results of Vitek 2 Compact system and KB method were compared with that of MTS. ResultsAmong the 140 multidrug-resistant isolates, 119 were Acinetobacter baumannii, and 21 were Enterobacteriaceae. According to the US Food and Drug Administration standards, the sensitivity rates of 119 Acinetobacter baumannii isolates to tigecycline were 88.2%, 85.7%, and 90.8% respectively for KB method, Vitek 2 Compact system and MTS, and those of 21 Enterobacteriaceae were 76.2%, 81.0%, and 81.0%, respectively. ConclusionsTigecycline displays effective in vitro antibacterial activity to clinical common multidrug-resistant bacteria (excluding Pseudomonas aeruginosa), but different susceptibility testing methods have shown different susceptibility rates. For Acinetobacter baumannii, KB method is superior to Vitek 2 Compact system, and for Enterobacteriaceae, Vitek 2 Compact system is superior to KB method.