Causative bacteria of ventilator-associated pneumonia in intensive care unit in Bahrain:Prevalence and antibiotics susceptibility pattern

BACKGROUND Ventilator-associated pneumonia(VAP)is defined as pneumonia that occurs two calendar days following endotracheal intubation or after that.It is the most common infection encountered among intubated patients.VAP incidence showed wide variability between countries.AIM To define the VAP incidence in the intensive care unit(ICU)in the central gove-rnment hospital in Bahrain and review the risk factors and the predominant bacterial pathogens with their antimicrobial susceptibility pattern.METHODS The research was a prospective cross-sectional observational study over six months from November 2019 to June 2020.It included adult and adolescent patients(>14 years old)admitted to the ICU and required intubation and mechanical ventilation.VAP was diagnosed when it occurred after 48 h after endotracheal intubation using the clinical pulmonary infection score,which considers the clinical,laboratory,microbiological,and radiographic evidence.RESULTS The total number of adult patients admitted to the ICU who required intubation and mechanical ventilation during the study period was 155.Forty-six patients developed VAP during their ICU stay(29.7%).The calculated VAP rate was 22.14 events per 1000 ventilator days during the study period,with a mean age of 52 years±20.Most VAP cases had late-onset VAP with a mean number of ICU days before the development of VAP of 9.96±6.55.Gram-negative contributed to most VAP cases in our unit,with multidrug-resistant Acinetobacter being the most identified pathogen.CONCLUSION The reported VAP rate in our ICU was relatively high compared to the international benchmark,which should trigger a vital action plan for reinforcing the implementation of the VAP prevention bundle.

Risk factors for ventilator-associated pneumonia in trauma patients:A descriptive analysis

BACKGROUND:We sought to evaluate the risk factors for developing ventilator-associated pneumonia(VAP)and whether the location of intubation posed a risk in trauma patients.METHODS:Data were retrospectively reviewed for adult trauma patients requiring intubation for>48 hours,admitted between 2010 and 2013.Patients’demographics,clinical presentations and outcomes were compared according to intubation location(prehospital intubation[PHI]vs.trauma room[TRI])and presence vs.absence of VAP.Multivariate regression analysis was performed to identify predictors of VAP.RESULTS:Of 471 intubated patients,332 patients met the inclusion criteria(124 had PHI and208 had TRI)with a mean age of 30.7±14.8 years.PHI group had lower GCS(P=0.001),respiratory rate(P=0.001),and higher frequency of head(P=0.02)and chest injuries(P=0.04).The rate of VAP in PHI group was comparable to the TRI group(P=0.60).Patients who developed VAP were 6 years older,had significantly lower GCS and higher ISS,head AIS,and higher rates of polytrauma.The overall mortality was 7.5%,and was not associated with intubation location or pneumonia rates.In the early-VAP group,gram-positive pathogens were more common,while gram-negative microorganisms were more frequently encountered in the late VAP group.Logistic regression analysis and modeling showed that the impact of the location of intubation in predicting the risk of VAP appeared only when chest injury was included in the models.CONCLUSION:In trauma,the risk of developing VAP is multifactorial.However,the location of intubation and presence of chest injury could play an important role.

Distribution and antibiotic resistance of pathogens isolated from ventilator-associated pneumonia patients in pediatric intensive care unit

BACKGROUND： With mechanical ventilation widely used in intensive care unit, the ventilator associated pneumonia （VAP） has become a common and serious complication in critically ill patients. Compared with adults, the incidence of VAP and the mortality are higher in children in pediatric intensive care unit （PICU） because of immune deficiency, severe basic diseases, and increased use of artificial airway or mechanical ventilation. Hence it is of significance to study the epidemiology and changes of antibacterial susceptibility in order to reduce the incidence and mortality of VAP in children.METHODS： From January 2008 to June 2010, 2758 children were treated in PICU of Wuhan Children＇s Hospital. Among them, 171 received mechanical ventilation over 48 hours in PICU, and 46 developed VAP. The distribution and drug-resistance pattern of the pathogenic bacteria isolated from lower respiratory tract aspirations were analyzed. RESULTS：A total of 119 pathogenic microbial strains were isolated. Gram-negative bacilli （G-） were the most （65.55%）, followed by fungi （21.01%） and gram-positive cocci （G~, 13.45%）. Among them, the most common pathogens were Acinetobacter baummannii, Escherichia coli, Klebsiella pneumoniae, candida albicans and coagulase-negative staphylococci. Antibiotic susceptibility tests indicated that the multiple drug-resistances of G- and G＋to antibiotics were serious. Most of G- was sensitive to ciprofloxacin, amikacin, imipenem, meropenem, cefoperazone-sulbactam and piperacillin-tazobactam. The susceptibility of G＋ to vancomycin, teicoplanin and linezolid were 100%. Fungi were almost sensitive to all the antifungal agents. The primary pathogens of VAP were G-, and their multiple drug-resistances were serious. CONCLUSION： In clinical practice we should choose the most sensitive drug for VAP according to pathogenic test.

Effect of traditional Chinese preparation Xuebijing on inflammatory markers in patients with ventilator-associated pneumonia

Objective:To observe the effect of Xuebijing,a complex traditional Chinese preparation,on inflammation and prognosis of patients with pneumonia.Methods:The patients with ventilator-associated pneumonia in the intensive care unit(ICU)were randomly divided into the control group and the treatment group with 35 cases in each group.Both groups were given routine treatment such as anti-inflammatory drugs,rehydration,expectorant,and nutritional support,while the treatment group was additionally given Xuebijing injection.Serum C-reactive protein(CRP),clinical pulmonary infection score(CPIS),acute physiology,and chronic health scoreⅡ(APACHEⅡ)were recorded before treatment,the 3rd and 7th day after treatment.The duration of antibiotic use,mechanical ventilation,ICU stay,and mortality during 28 days was recorded.Results:There was no significant difference in CRP,CPIS,and APACHEⅡbetween the two groups before treatment(P>0.05).The improvement of CRP,CPIS,and APACHEⅡin the treatment group was better than those in the control group on the 3 and 7 days after treatment,and the differences were statistically significant(P<0.05).The duration of antibiotic use,mechanical ventilation,and ICU stay in the treatment group were less than those in the control group(P<0.05).The 28-day mortality of the treatment group was lower than that of the control group,but the difference was not statistically significant(P>0.05).Conclusions:Xuebijing injection can improve the inflammatory indexes of patients with ventilator-associated pneumonia,and can partly improve the prognosis.

Respiratory mechanics,ventilator-associated pneumonia and outcomes in intensive care unit

AIM To evaluate the predictive capability of respiratory mechanics for the development of ventilator-associated pneumonia (VAP) and mortality in the intensive care unit(ICU) of a hospital in southern Brazil. METHODS A cohort study was conducted between, involving a sample of 120 individuals. Static measurements of compliance and resistance of the respiratory system in pressure-controlled ventilation (PCV) and volumecontrolled ventilation(VCV) modes in the 1 st and 5 th days of hospitalization were performed to monitor respiratory mechanics. The severity of the patients' illness was quantified by the Acute Physiology and Chronic Health Evaluation Ⅱ (APACHE Ⅱ). The diagnosis of VAP was made based on clinical, radiological and laboratory parameters.RESULTS The significant associations found for the development of VAP were APACHE Ⅱ scores above the average(P = 0.016), duration of MV (P = 0.001) and ICU length of stay above the average(P = 0.003), male gender(P = 0.004), and worsening of respiratory resistance in PCV mode(P = 0.010). Age above the average(P < 0.001), low level of oxygenation on day 1(P = 0.003) and day 5 (P = 0.004) and low lung compliance during VCV on day 1 (P = 0.032) were associated with death as the outcome.CONCLUSION The worsening of airway resistance in PCV mode indicated the possibility of early diagnosis of VAP. Low lung compliance during VCV and low oxygenation index were death-related prognostic indicators.

Antimicrobial resistance pattern in ventilator-associated pneumonia in an intensive care unit of Babol, northern Iran

Objective:To investigate antibiotic resistance pattern of ventilator-assiated pneumonia (VAP) generating microorganisms,and quantitative culture and determining antibiotic sensitivity.Methods:This cross sectional study was performed on 50 patients suffering from VAP in intensive care unit of Ayatollah Rouhani Hospital,Babol,Iran during 2014-2015.VAP was probable for them based on clinical signs and the criteria of Clinical Pulmonary Infection Score standards.Lower respiratory samples were given under bronchoalveolar lavage and quantitative culture was done on them.Afterwards by microdilution method,minimal inhibitory concentration based on respective microorganisms,considering clinical pulmonary infection score were determined.Results:From 50 investigated samples in this study,the most common microorganisms were Acinetobacter baumannii (A.baumannii) (70%) then Pseudomonas aeruginosa (12%),Staphylococcus aureus (8%) and Klebsiella pneumonia (3%).In our study A.baummannii showed approximate 100% resistance to all antibiotics,in a way that A.baumannii resistance to imipenem and meropenem and piperacillin/tazobactam each was 97.1%.The most resistance of Pseudomonas aeruginosa was 66.7% to each cefepime and ceftazidime and clavulanate/ticarcillin.Staphylococcus aureus showed 75% resistance to nafcillin,cloxacillin and resistance in case of vancomycin was not seen.Conclusion:In current study,A.baumannii had the most prevalence among VAP and this species is resistant to most of antibiotics.Using ceftazidime,cefepime and clavulanate/ticarcillin,in treatment of the patients suffering VAP is not reasonable.

Ventilator-associated pneumonia in patients with cancer: Impact of multidrug resistant bacteria

BACKGROUND Patients with cancer have several risk factors for developing respiratory failure requiring mechanical ventilation(MV).The emergence of multidrug resistant bacteria(MDRB)has become a public health problem,creating a new burden on medical care in hospitals,particularly for patients admitted to the intensive care unit(ICU).AIM To describe risk factors for ventilator-acquired pneumonia(VAP)in patients with cancer and to evaluate the impact of MDRB.METHODS A retrospective study was performed from January 2016 to December 2018 at a cancer referral center in Mexico City,which included all patients who were admitted to the ICU and required MV≥48 h.They were classified as those who developed VAP versus those who did not;pathogens isolated,including MDRB.Clinical evolution at 60-d was assessed.Descriptive analysis was carried out;comparison was performed between VAP vs non-VAP and MDRB vs non-MDRB.RESULTS Two hundred sixty-three patients were included in the study;mean age was 51.9 years;52.1%were male;68.4%had solid tumors.There were 32 episodes of VAP with a rate of 12.2%;11.5 episodes/1000 ventilation-days.The most frequent bacteria isolated were the following:Klebsiella spp.[n=9,four were Extended-Spectrum Beta-Lactamase(ESBL)producers,one was Carbapenem-resistant(CR)];Escherichia coli(n=5,one was ESBL),and Pseudomonas aeruginosa(n=8,two were CR).One Methicillin-susceptible Staphylococcus aureus was identified.In multivariate analysis,the sole risk factor associated for VAP was length of ICU stay(OR=1.1;95%CI:1.03-1.17;P=0.003).Sixty-day mortality was 53%in VAP and 43%without VAP(P=0.342).There was not higher mortality in those patients with MDRB.CONCLUSION This study highlights the high percentage of Gram-negative bacteria,which allows the initiation of empiric antibiotic coverage for these pathogens.In this retrospective,single center,observational study,MDRB VAP was not directly linked to increased mortality at 60 days.

Natural History, Outcomes and Antibiotic Treatment for Ventilator-Associated Tracheobronchitis in Critical Ill Patients

We assessed incidence and outcomes of patients with ventilator-associated respiratory infections (VARI) due to tracheobronchitis (VAT) and pneumonia (VAP), including length of intensive care unit (ICU) stay and ventilator days. We also examined pathogens, rate of progression from VAT to VAP, and impact of antibiotic therapy for VAT. Data analysis included 234 patients, 100 patients (43%) had at least moderate (+++) bacterial growth in their semi-quantitative endotracheal aspirate (SQ-ETA) cultures. VAT and VAP were each diagnosed in 34 (15%) patients. Staphylococcus aureus was the most common pathogen isolated and had the highest rate of progression from VAT to VAP. Seven (21%) of the 34 patients were diagnosed with VAT that later progressed to VAP in averaged 3 days. Patients diagnosed with VAT had significantly more ventilator days (9 vs 6, p p < 0.001) and hospital days (22 vs 17, p < 0.001). No significant difference was observed in the clinical outcomes of the 25 VAT patients with timely, appropriate antibiotics compared to the 9 VAT patients who did not receive timely appropriate antibiotics. VAT was a risk factor for increased ventilator days, longer length of ICU and hospital stay. The time window from VAT to VAP allowed physicians to identify the pathogens and sensitivity profile needed to treat VAT with appropriate antibiotics. Data from well-designed studies were needed to assess the impact of early, appropriate antibiotic therapy for VAT, the choice of antibiotics, as well as the duration and route of administration.

Ventilator-associated events: From surveillance to optimizing management

Mechanical ventilation(MV)is a life-support therapy that may predispose to morbid and lethal complications,with ventilator-associated pneumonia(VAP)being the most prevalent.In 2013,the Center for Disease Control(CDC)defined criteria for ventilator-associated events(VAE).Ten years later,a growing number of studies assessing or validating its clinical applicability and the potential benefits of its inclusion have been published.Surveillance with VAE criteria is retrospective and the focus is often on a subset of patients with higher thanlower severity.To date,it is estimated that around 30%of ventilated patients in the intensive care unit(ICU)develop VAE.While surveillance enhances the detection of infectious and non-infectious MV-related complicationsthat are severe enough to impact the patient’s outcomes,there are still many gaps in its classification and management.In this review,we provide an update by discussing VAE etiologies,epidemiology,and classification.Preventive strategies on optimizing ventilation,sedative and neuromuscular blockade therapy,and restrictivefluid management are warranted.An ideal VAE bundle is likely to minimize the period of intubation.We believethat it is time to progress from just surveillance to clinical care.Therefore,with this review,we have aimed toprovide a roadmap for future research on the subject.

新建综合性ICU呼吸机相关性肺炎病原菌分析

目的了解新建综合性重症监护病房(ICU)中呼吸机相关性肺炎(VAP)病原菌的分布及耐药性特点,为临床用药提供参考资料。方法对2005年9月-2007年1月确诊VAP患者分离到的病原菌进行鉴定,并采用纸片扩散法进行药物敏感试验。结果VAP病原菌中革兰阴性菌为主,占70.5%,革兰阳性菌其次占24.6%,真菌占4.9%;位于前5位的病原菌依次为铜绿假单胞菌、金黄色葡萄球菌、鲍氏不动杆菌、大肠埃希菌、嗜麦芽寡养单胞菌;亚胺培南、美罗培南对主要的革兰阴性菌具有相对较好的敏感性,哌拉西林/他唑巴坦对铜绿假单胞菌有较好的敏感性;革兰阳性菌主要为MRSA,成为VAP病原菌的第2位,对万古霉素100.0%敏感。结论革兰阴性杆菌仍是新建ICU导致VAP的主要病原菌,且对多种抗菌药物耐药,MRSA成为VAP第2位的病原菌。

腹部手术后肺部感染痰涂片、培养及药敏分析

目的 :了解腹部手术后肺部感染的细菌分布及药敏情况。方法 :对 1997年 1月～ 2 0 0 0年 8月期间属腹部手术后肺部感染获送检的 738个痰标本进行回顾性调查分析。结果 :腹部手术后肺部感染的最常见病原体依次为鲍曼不动杆菌、铜绿假单胞菌、金黄色葡萄球菌、肺炎克雷伯菌、表皮葡萄球菌和阴沟肠杆菌。大多数细菌均有较高程度的耐药性。革兰阳性菌对万古霉素的敏感率达 98.9% ,革兰阴性杆菌对头孢拉啶的敏感率为 5 1.3%。痰标本合格率为 71.7%。结论 :万古霉素和(或 )头孢拉啶可作为经验性治疗腹部手术后严重肺部感染的首选用药。痰涂片不但可以判断痰标本是否合格 ,还可以判断肺部感染是否被控制。

三种方案治疗金黄色葡萄球菌肺炎临床及实验室研究

目的探讨阿奇霉素、阿奇霉素分别与痰热清、炎琥宁联合治疗金黄色葡萄球菌肺炎临床及实验室疗效。方法将49例患儿随机分成3组,分别给予静脉滴注阿奇霉素5～10mg·kg-1·d-1;阿奇霉素+痰热清0.5mg·kg-1·d-1;阿奇霉素+炎琥宁8～10mg·kg-1·d-1;7d为1个疗程。实验室将健康家兔30只分为3组,3组按临床同样方法给药,按生物法测定抑菌圈。结果 3种方案退热时间、咳嗽消失时间、肺内音消失时间、住院时间比较差异有统计学意义(P<0.05)。结论阿奇霉素与痰热清联合协同作用强,与炎琥宁联合协同作用弱。

玉屏风颗粒辅助治疗小儿难治性支原体肺炎的临床观察

目的探讨玉屏风颗粒辅助治疗小儿难治性支原体肺炎(RMPP)的临床效果及对炎症因子和免疫功能的影响。方法将80例RMPP患儿随机分为观察组和对照组各40例,其中对照组给予大环内酯类抗生素序贯治疗,观察组在此基础上给予玉屏风颗粒进行辅助治疗,观察两组临床治疗效果、炎症因子和免疫功能变化情况。结果治疗组患儿在咳嗽咳痰消失时间(6.25±1.63)d、喘息消失时间(5.38±1.34)d、高热消退时间(3.36±0.39)d、肺部啰音消失时间(4.34±2.45)d,以及肺阴影消失时间(8.23±3.96)d,明显低于对照组(8.44±2.22、7.85±1.43、4.56±0.56、5.86±2.57、10.43±3.85)d,差异均有显著的统计学意义(P<0.01);观察组TNF-α、IL-4、IL-6、IL-10和CD+8明显低于对照组,而IL-2、CD_3^+,CD_4^+和CD_4^+/CD_8^+水平明显高于对照组,差异均有显著的统计学意义(P<0.01),两组患儿免疫球蛋白水平治疗前后水平差异无统计学意义(P>0.05),两组患儿均未发生明显的不良反应。结论玉屏风颗粒辅助治疗RMPP临床疗效确切,抑制患儿炎症因子和改善患儿的免疫功能紊乱可能是作用机制之一。

Outcomes and risk factors of ventilator-associated pneumonia in neonates

Background:Ventilator-associated pneumonia (VAP) in neonates has been associated with high mortality and poor outcome.This study aimed to compare the incidence,risk factors,and outcomes of VAP and nonVAP conditions in neonates.Methods:We performed a prospective cohort study in a neonatal intensive care unit (NICU) in Thailand from January 2014 to December 2014.All neonatal patients who were ventilated more than 48 hours were enrolled.Results:There were 128 enrolled patients.The median (inter quartile range) gestational age and birthweight were 35 (30.2,37.8) weeks and 2380 (1323.8,3020.0) g.There were 17 VAP patients (19 episodes) and 111 non-VAP ones.The VAP rate was 13.3% or 10.1 per 1000 ventilator days.According to the multivariate analysis,a birthweight less than 750 g [adjusted odds ratio (aOR)=10.75,95% confidence interval (CI)=2.35-49.16;P=0.002] and sedative medication use (aOR=4.00,95% CI=1.23-12.50;P=0.021)were independent risk factors for VAP.Compared with the non-VAP group,the median difference in the VAP group yielded a significantly longer duration of NICU stay (18 days,P=0.001),total length of hospital stay (16 days,P=0.002) and higher hospital costs ($5113,P=0.001).The inhospital mortality rate in the VAP and non-VAP groups was 17.6% and 15.3% (P=0.73),respectively.Conclusions:A neonatal birthweight less than 750 g and sedative medication use were independent risk factors for VAP.Our VAP patients experienced a longer duration of both NICU and hospital stay,and incurred higher hospitalization costs.

Antibiotics De-Escalation in the Treatment of Ventilator-Associated Pneumonia in Trauma Patients： A Retrospective Study on Propensity Score Matching Method

Background： Antimicrobial de-escalation refers to starting the antimicrobial treatment with broad-spectrum antibiotics, followed by narrowing the drug spectrum according to culture results. The present study evaluated the effect of de-escalation on ventilator-associated pneumonia （VAP） in trauma patients. Methods： This retrospective study was conducted on trauma patients with VAP, who received de-escalation therapy （de-escalation group） or non-de-escalation therapy （non-de-escalation group）. Propensity score matching method was used to balance the baseline characteristics between both groups. The 28-day mortality, length of hospitalization and Intensive Care Unit stay, and expense of antibiotics and hospitalization between both groups were compared. Multivariable analysis explored the factors that influenced the 28-day mortality and implementation of de-escalation. Results： Among the 156 patients, 62 patients received de-escalation therapy and 94 patients received non-de-escalation therapy. No significant difference was observed in 28-day mortality between both groups （28.6% vs. 23.8%, P = 0.620）. The duration of antibiotics treatment in the de-escalation group was shorter than that in the non-de-escalation group （11 [8-13] vs. 14 [8-19] days, P = 0.045）. The expenses of antibiotics and hospitalization in de-escalation group were significantly lower than that in the non-de-escalation group （6430 ± 2730 vs. 7618 ± 2568 RMB Yuan, P = 0.043 and 19,173 ± 16,861 vs. 24,184 ± 12,039 RMB Yuan, P = 0.024, respectively）. Multivariate analysis showed that high Acute Physiology and Chronic Health Evaluation Ⅱ （APACHE Ⅱ） score, high injury severity score, multi-drug resistant （MDR） infection, and inappropriate initial antibiotics were associated with patients＇ 28-day mortality, while high APACHEⅡ score, MDR infection and inappropriate initial antibiotics were independent factors that prevented the implementation of de-escalation. Conclusions： De-escalation strategy in the treatment of trauma patients with VAP could reduce the duration of antibiotics treatments and expense of hospitalization, without increasing the 28-day mortality and MDR infection.

Aerosolized Amikacin as Adjunctive Therapy of Ventilator-associated Pneumonia Caused by Multidrug-resistant Gram-negative Bacteria： A Single-center Randomized Controlled Trial

Background： Aerosolized amikacin （AA） is a current option for the management of ventilator-associated pneumonia （VAP） caused by multidrug-resistant Gram-negative bacteria （MDR-GNB）, as it is reported that AA could increase the alveolar level of the drug without increasing systemic toxicity. This study aimed to evaluate the efficacy and safety of AA as an adjunctive therapy for VAP caused by MDR-GNB. Methods： In this single-center, double-blind study conducted in a 36-bed general Intensive Care Unit （ICU） in a tertiary hospital from June 2014 to June 2016, 52 ICU patients with confirmed MDR-GNB VAP were randomized to two groups （AA group, n - 27 and placebo group, n = 25）. Amikacin （400 rag, q8h） or saline placebo （4 ml, q8h） was aerosolized for 7 days. The attending physician determined the administration of systemic antibiotics for VAP. Patients were tbllowed up for 28 days. Bacteriological eradication, clinical pulmonary infection score （CP1S）, and serum creatinine were assessed on day 7 of therapy. New resistance to amikacin, cure rate of VAP, weaning rate, and mortality were assessed on day 28. Results： The baseline characteristics of patients in both groups were similar. At the end of the treatment, 13 of the 32 initially detected bacterial isolates were eradicated in AA group, compared to 4 of 28 in placebo group （41% vs. 14%, P - 0.024）. As for patients, 11 of 27 patients treated with AA and 4 of 25 patients treated with placebo have eradication （41% vs. 16%, P = 0.049）. The adjunction of AA reduced CPIS （4.2 ± 1.6 vs. 5.8 ± 2.1, P = 0.007）. New drug resistance to amikacin and the change in serum creatinine were not detected in AA group. No significant differences in the clinical cure rate in survivors （48% vs. 35%, P = 0.444）, weaning rate （48% vs. 32%, P = 0.236）, and mortality （22% vs. 32%, P = 0.427） were detected between the two groups on day 28. Conclusions： As an adjunctive therapy of MDR-GNB VAP, AA successfully eradicated existing MDR organisms without inducing new resistance to amikacin or change in serum creatinine. However, the improvement of mortality was not found.

Risk factors and clinical responses of pneumonia patients with colistin-resistant Acinetobacter baumannii-calcoaceticus

BACKGROUND Nosocomial infections with carbapenem-resistant Acinetobacter baumanniicalcoaceticus complex(ABC)strains are great problem for intensive care units.ABC strains can develop resistance to all the antibiotics available.Carbapenem resistance is common and colistin resistance is rare in our country.Knowing the risk factors for colistin resistance is important since colistin seems to be the only remaining therapeutic option for the patients with pneumonia due to extensively drug resistant ABC for our country.AIM To investigate the comparison of clinical responses and outcomes between pneumonia patients with colistin-susceptible and-resistant Acinetobacter sp.Strains.METHODS During the study period,108 patients with pneumonia due to colistin-susceptible strains and 16 patients with colistin-resistant strains were included retrospectively.Continuous variables were compared with the Mann-Whitney U test,and categorical variables were compared using Pearson’s chi-square test or Fisher’s Exact chi-square test for two groups.A binary logistic regression model was developed to identify the potential independent factors associated with colistin resistance in patients with colistin-resistant strains.RESULTS High Acute Physiology and Chronic Health Evaluation II scores(OR=1.9,95%CI:1.4-2.7;P<0.001)and prior receipt of teicoplanin(OR=8.1,95%CI:1.0-63.3;P=0.045)were found to be independent risk factors for infection with colistin-resistant Acinetobacter sp.Different combinations of antibiotics including colistin,meropenem,ampicillin/sulbactam,amikacin and trimethoprim/sulfamethoxazole were used for the treatment of patients with colistin-resistant strains.Although the median duration of microbiological cure(P<0.001)was longer in the colistin-resistant group,clinical(P=0.703),laboratory(P=0.277),radiological(P=0.551),microbiological response(P=1.000)and infection related mortality rates(P=0.603)did not differ between the two groups.Among the patients with infections due to colistin-resistant strains,seven were treated with antibiotic combinations that included sulbactam.Clinical(6/7)and microbiological(5/7)response rates were quite high in these patients.CONCLUSION The optimal therapy regimen is unclear for colistin-resistant Acinetobacter sp.infections.Although combinations with sulbactam seems to be more effective in our study patients,data supporting the usefulness of combinations with sulbactam is very limited.

Microscopic examination of intracellular organisms in bronchoalveolar lavage fluid for the diagnosis of ventilator-associated pneumonia：a prospective multi-center study

Background The presence of intracellular organisms （ICOs） in polymorphonuclear leukocytes obtained from bronchoalveolar lavage fluid （BALF） is a possible method for rapid diagnosis of ventilator-associated pneumonia （VAP）.However,the validity of this diagnostic method remains controversial and the diagnostic thresholds reported by investigators were different.Our objective was to evaluate the accuracy of quantification of ICOs in BALF for the diagnosis of VAP,and to detect the best cutoff percentage of PMNs containing ICOs （PIC） in the microscopic examination of BALF for the diagnosis of VAP.Methods This was a prospective multi-center study conducted in 4 ICUs in Wuhan,China,which involved 181 patients suspected of first episode of VAP.BALF was obtained from all enrolled patients.The BALF samples underwent quantitative culture,cytological and bacteriological analysis to detect the culture results,PIC values and the morphological features of microorganisms.Definite diagnosis of VAP was based on pre-set criteria.The receiver-operating characteristic curve was used to detect the best cutoff point for PIG to diagnose VAP,and the diagnostic accuracy was calculated.Moreover,quantitative culture and Gram＇s stain of BALF were adopted to diagnose VAP,and their diagnostic accuracy was evaluated as well.Results There were 102 patients definitely diagnosed with VAP （VAP group）,and 60 patients definitely diagnosed without VAP （no VAP group）.We found that ICOs were present in 96.08％ （98 out of 102） of VAP patients and 20.00％ （12 out of 60） of no VAP patients.The PICs were significantly higher （（9.53±6.65）％ vs.（0.52±1.33）％,P＜0.01） in VAP group.In our study,the best cutoff point for PIC to diagnose VAP was 1.5％,which had a sensitivity of 94.12％,a specificity of 88.33％,a positive predictive value （PPV） of 93.20％ and a negative predictive value （NPV） of 89.83％.The area under the receiveroperating characteristic curve was 0.956 （95％ confidence interval,0.925-0.986; P＜0.01）.When the positive quantitative culture results of BALF were used to diagnose VAP,the sensitivity,specificity,PPV and NPV were 65.69％,95.00％,95.71％ and 61.96％,respectively.Whereas they were 70.59％,76.67％,83.72％ and 60.53％,respectively,when the positive Gram＇s stain results of BALF were used to diagnose VAP.The concordance between the results of Gram＇s stain and quantitative cultures was poor,only 32.10％ （52 out of 162） was totally right,and 17.28％ （28 out of 162） was partially right.Conclusions PIC＞1.5％ has good diagnostic performance in the microscopic examination of BALF for the diagnosis of VAP.However,Gram＇s stain is not reliable for the early application of antibiotic therapy,due to the poor bacteriological predictive value.

Interpretation for practice guidelines for prevention, diagnosis, and treatment of ventilator-associated pneumonia in burn patients by american burn association

"American Burn Association Practice Guidelines for Prevention,Diagnosis,and Treatment of Ventilator-Associated Pneumonia in Burn Patients"was published to provide recommendation for the prevention,diagnosis,and treatment of ventilator-associated pneumonia in burn patients.This article makes interpretations and conclusions for prevention,diagnosis and treatment from this guideline in the combination of domestic burn patients.

Device-associated infection rates, mortality, length of stay and bacterial resistance in intensive care units in Ecuador: International Nosocomial Infection Control Consortium's findings

AIM To report the results of the International Nosocomial Infection Control Consortium(INICC) study conducted in Quito, Ecuador.METHODS A device-associated healthcare-acquired infection(DAHAI) prospective surveillance study conducted from October 2013 to January 2015 in 2 adult intensive care units(ICUs) from 2 hospitals using the United States Centers for Disease Control/National Healthcare Safety Network(CDC/NHSN) definitions and INICC methods. RESULTS We followed 776 ICU patients for 4818 bed-days. The central line-associated bloodstream infection(CLABSI) rate was 6.5 per 1000 central line(CL)-days, the ventilator-associated pneumonia(VAP) rate was 44.3 per 1000 mechanical ventilator(MV)-days, and the catheterassociated urinary tract infection(CAUTI) rate was 5.7 per 1000 urinary catheter(UC)-days. CLABSI and CAUTI rates in our ICUs were similar to INICC rates [4.9(CLABSI) and 5.3(CAUTI)] and higher than NHSN rates [0.8(CLABSI) and 1.3(CAUTI)]- although device use ratios for CL and UC were higher than INICC and CDC/NSHN's ratios. By contrast, despite the VAP rate was higher than INICC(16.5) and NHSN's rates(1.1), MV DUR was lower in our ICUs. Resistance of A. baumannii to imipenem and meropenem was 75.0%, and of Pseudomonas aeruginosa to ciprofloxacin and piperacillin-tazobactam was higher than 72.7%, all them higher than CDC/NHSN rates. Excess length of stay was 7.4 d for patients with CLABSI, 4.8 for patients with VAP and 9.2 for patients CAUTI. Excess crude mortality in ICUs was 30.9% for CLABSI, 14.5% for VAP and 17.6% for CAUTI. CONCLUSION DA-HAI rates in our ICUs from Ecuador are higher than United States CDC/NSHN rates and similar to INICC international rates.