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.
自上世纪90 年代以来, 多耐药非发酵革兰阴性杆菌开始成为医院感染的重要病原菌, 并迅速增加, 其中不动杆菌( Acinetobacter) 尤其令人关注。鲍曼不动杆菌( Acinetobacter baumannii) 或称鲍曼-醋酸钙不动杆菌复合群, 占不动杆菌的80% ～90% , 是不动杆菌中引起人类感染的主要菌群, 具有极强的环境适应能力、获得外源性耐药基因的能力及播散性, 因而被称为21 世纪革兰阴性菌中的“耐甲氧西林金黄色葡萄球菌( MRSA) ”, 值得引起临床医生的重视。
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 efficacy and safety of colistin in the treatment of severe infections. Methods PubMed, ISI Web of Knowledge and Wanfang databases were searched. The initial literatures and references listed in the literature were manually searched. Controlled studies were analyzed using RevMan 5. 0 software.Results Eleven studies were enrolled, including five prospective studies and six retrospective studies. Pooled analysis showed that, compared with other therapies, treatment with colistin in severe infections did not improve 28 or 30-day mortality, clinical symptoms, or bacteria clearance,however, increased the risk of kidney damage. Subgroup analysis showed that colistin did not improve symptoms, mortality ( which was even higher in the patients with drug resistant bacteria infection) , or kidney damage in drug resistant bacteria infections and ventilator associated pneumonia ( VAP) compared with the other antibiotic group. Conclusions Colistin is not superior to the other antibiotics in severe infections.However, there are some shortcomings in our meta-analysis due to limited high-quality RCTs, thus welldesigned RCTs are still needed before final conclusion is made.
ObjectiveTo investigate the distribution and drug resistance of Acinetobacter baumannii (AB) in a women and children's hospital. MethodsStrains of AB isolated from clinical specimens between January 2011 and December 2013 were identified with Vitek2-compact microbiology analyzer; antimicrobial susceptibility test was performed by Kirby-Bauer disk diffusion method. The resistant rate, intermediate rate and susceptibility rate of drugs were calculated according to the criteria in guidelines of Clinical and Laboratory Standards Institute. WHONET 5.6 software was used to analyze the data. ResultsA total of 167 strains of AB were isolated and tested. Neonatal ward had the highest detection proportion. Most strains of AB were isolated from sputum. The drug resistance rate of AB to piperacillin tazobactam, cefepime and carbapenem was<25%. ConclusionThe drug sensitivity rate of AB to piperacillin/tazobactam, cefepime and carbapenems was high, but drug resistence to antimicrobial drugs increased continuously in three years. Medical institutions should strengthen the monitoring of AB resistance, implement rational use of antibiotics, and carry out hand hygiene education, to reduce the generation and dissemination of AB resistant strains.
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.
Objective To review the clinical features and trend in antimicrobial resistance of Acinetobacter baumannii (A. baumannii) bloodstream infections. Methods Retrospective analysis was performed by collecting data of underlying diseases, potential risk factors, clinical characteristics, blood test results, Acute Physiology and Chronic Health EvaluationⅡ (APACHEⅡ) scores at onset, bacterial resistance to antibiotics and antimicrobial therapy were collected in Hunan Provincial People’s Hospital from January 2010 to June 2016. Results There were 114 non-duplicated A. baumannii complex blood isolates identified in this research. All patients had at least one underlying disease and accepted at least one surgery or invasive operation within the past 14 days. Multidrug-resistant A. baumannii (MDRAB) was isolated from 89 (78.1%) patients. Of the 114 strains of A. baumannii, 12.3% were resistant to tigecycline, 55.3% to amikacin and 61.4% to cefoperazone-sulbactam. The overall mortality was 51.8% (59/114). The patients with MDRAB had higher mortality rate than those with non-MDRAB (62.9% vs. 12.0%, χ2=20.268, P<0.001). With higher incidence of being in the intensive care unit, intubation/tracheotomy and increased APACHEⅡ score among patients with MDRAB bacteremia (P<0.05). Compared with subjects treated with tigecycline based regimen, those treated with non tigecycline for multidrug resistantA. baumannii had a higher mortality (64.8% vs. 60.0%) but there was no statistical significance (P>0.05). Conclusions The isolated A. baumannii are mainly multidrug resistant and with high mortality. Being in the intensive care unit, increased APACHEⅡ score and intubation/tracheotomy were risk factors for higher mortality among patients with MDRAB bloodstream infection. Tigecycline based regimen doesn’t improve patients’ prognosis.
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.
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.