中性粒细胞/淋巴细胞比值对血流感染的诊断价值

目的探讨5项感染标志物对血流感染的诊断价值。方法随机选取望京医院血培养阳性的血流感染患者110例为研究组,血培养阴性的细菌感染患者30例为对照组。在血培养的同1天抽取静脉血,检测全血细胞计数和C反应蛋白(CRP)。比较两组白细胞(WBC)、中性粒细胞(NEU)、淋巴细胞(LYM)、中性粒细胞/淋巴细胞比值(NLCR)和CRP的差异。结果血流感染组WBC、NEU、NLCR、CRP均显著高于对照组(P0.05),而LYM显著低于对照组(P0.05)。5项感染标志物中,NLCR和LYM诊断血流感染的受试者工作特征曲线下面积(ROC-AUC)分别为0.808和0.756。当NLCR取临界值为9.33时,敏感性为63.6%,特异性为93.3%;LYM小于等于0.97为临界值时,敏感性为58.2%,特异性为86.7%。进一步,在血培养阳性患者中,革兰氏阴性菌所致的血流感染组的NLCR高于革兰氏阳性菌血流感染组,NLCR在区分血流感染的类型中具有重要的临床意义。结论 NLCR优于其他常规感染指标,有助于血流感染的诊断。     

Nosocomial bloodstream infections caused by Streptococcus pneumoniae

A retrospective study of Streptococcus pneumoniae bacteraemia among adult patients in two large teaching hospitals in Spain identified 108 (10.6%) of 1,020 episodes as nosocomial pneumococcal bloodstream infections (NPBIs). Seventy-seven clinical records with sufficient data were available for analysis. The interval between admission and a positive blood culture was 3--135 days (median 17 days; interquartile range 8--27). The main underlying and predisposing conditions for NPBI were malignancy (31%), chronic obstructive pulmonary disease (28.6%), heart failure (16.9%), chronic renal failure (15.6%), liver cirrhosis (13%) and infection with human immunodeficiency virus (13%). Overall, 31.2% of patients developed severe sepsis, 11.7% septic shock, and 3.9% multi-organ failure. The main portals of entry were pneumonia (70.1%), meningitis (5.2%) and primary peritonitis (5.2%). Of the responsible serogroups, 78% were included in the 23-valent polysaccharide vaccine. Thirty-five (45.5%) patients died, with death considered to be related to the NPBI in 21 (27.3%) cases. Following multivariate analysis, factors that independently predicted death after adjusting for age were: ultimately fatal underlying disease (OR, 8.9; 95% CI, 0.8--94.3; p<0.001); rapidly fatal underlying disease (OR, 15.0; 95% CI, 2.8--81.3; p<0.001); heart failure (OR, 8.11; 95% CI, 1.1--60.8; p<0.03); inadequate empirical therapy (OR, 10.6; 95% CI, 1.2--97; p<0.003); a severe sepsis score (OR, 9.5; 95% CI, 1.9--47.0; p<0.001); and septic shock or multi-organ failure (OR, 63.7; 95% CI, 4.9--820.7; p<0.001). Adequate empirical therapy was an independent protective factor (OR, 0.05; 95% CI, 0.04--0.58; p<0.005), but the use of more than one antimicrobial agent was not.     

Risk-adjusted comparisons of bloodstream infection rates in neonatal intensive-care units

Comparisons of bloodstream infection (BSI) rates between neonatal intensive-care units (NICUs) should take into account differences in babies' vulnerability and invasive procedures that can introduce infection. Our aim was to investigate which risk factors recorded in routine records should be adjusted for when NICUs are compared. This was a retrospective cohort study using routine records for two London NICUs. We analysed rates of BSI with Poisson regression models. The level of neonatal care used by the National Health Service was the strongest predictor of BSI incidence. The rate ratios for BSI, adjusted for birthweight, inborn/outborn status, and postnatal age, were 3.15 (95% CI 2.01–4.94) for intensive care and 6.58 (95% CI 4.18-10.36) for high-dependency care, relative to special care. Total parenteral nutrition was significantly associated with BSI incidence, but explained less of the variance among babies than level of care. A case—control study with the same dataset gave similar results. Further multicentre studies are required to confirm our predictive model. Until then, we recommend that comparisons of BSI rates between NICUs should include adjustments for level of care, birthweight, inborn/outborn status, and postnatal age, with the use of routinely recorded standardized measures in hospital administrative data.     

肝移植术后耐甲氧西林金黄色葡萄球菌血流感染危险因素的17年回顾性分析

目的探讨本院肝移植术后耐甲氧西林金黄色葡萄球菌（MRSA）血流感染的危险因素及临床结果。方法回顾分析1993年1月至2010年5月肝移植术后血液MRSA阳性感染者的资料。结果 695例肝移植患者中,53例（7.6%）出现革兰氏阳性球菌血流感染,以肠球菌最为常见,7例病人发生7次MRSA血流感染。分析肝移植术后MRSA血流感染的危险因素发现,急性排斥（P=0.03）是出现MRSA血流感染的危险因素。肝移植术后MRSA血流感染与非MRSA血流感染的15d、30d、1年病死率差异无统计学意义。结论急性排斥是出现肝移植术后MRSA血流感染的危险因素,但肝移植术后MRSA血流感染后15d、30d、1年的死亡率未明显增加。     

Evolution and aetiological shift of catheter-related bloodstream infection in a whole institution: the microbiology department may act as a watchtower

The incidence of central-line-associated bloodstream infection (CLA-BSI) is reported per 1000 days of catheter exposure, mainly in the intensive care unit (ICU), because recording exposure throughout an institution is not always feasible. Confirmation of catheter-related bloodstream infection (CR-BSI) requires specific laboratory testing that identifies the catheter as the source of infection. This information is available in microbiology laboratories and can be assessed using a denominator of 1000 admissions. We evaluated recent trends in the incidence and aetiology of CR-BSI and compared adult ICUs with the remaining areas of the hospital in a retrospective cohort analysis of all confirmed CR-BSIs. During the 8-year study period, we recorded 1208 episodes (8.2% of BSIs) of CR-BSI. After adjusting for the blood cultures drawn, a significant reduction in incidence was observed in adult ICUs (47%), where care bundles had been applied. The reduction was similar irrespective of whether CLA-BSI or CR-BSI was assessed. We recorded a significant reduction in the incidence of Staphylococcus aureus CR-BSI, and a significant increase in the incidence of CR-BSI caused by Enterococcus sp., Gram-negative microorganisms and fungi. The microbiology department may complement CLA-BSI/1000 catheter-days by providing CR-BSI when days of exposure are not available, because both figures are parallel. We demonstrated a significant reduction in the incidence of CR-BSI in recent years in the population admitted to adult ICUs but not in the remaining areas of the hospital. A shift in the aetiological spectrum of CR-BSI may be occurring.     

Prognostic value of central venous-to-arterial carbon dioxide difference in patients with bloodstream infection

Background: Bloodstream infection (BSI) are prone to circulation disorders, which portend poor outcome. The central venous-to-arterial carbon dioxide difference (Pcv-aCO₂) is a biomarker for circulation disorders, but the prognostic value of Pcv-aCO₂ in BSI patients remains unclear. This study was to investigate the association of Pcv-aCO₂ with adverse events in BSI patients.Methods: The patients with BSI between August 2014 and August 2017 were prospectively enrolled. Clinical characteristic and laboratory results were collected. We analyzed the association of the level of Pcv-aCO₂ with clinical variables and 28-day mortality.Results: A total of 152 patients were enrolled. The Pcv-aCO₂ was positively correlated with white blood cell count (r=0.241, p=0.003), procalcitonin (r=0.471, p<0.001), C-reactive protein (r=0.192, p=0.018), lactate (r=0.179, p=0.027), Sequential Organ Failure Assessment (r=0.318, p<0.001) and Acute Physiology And Chronic Health Evaluation II score (r=0.377, p<0.001), while that was negatively correlated with central venous oxygen saturation (r=-0.242, p<0.001) and platelet (r=-0.205, p=0.011). Kaplan-Meier curves demonstrated that patients with Pcv-aCO₂ >6mmHg had a worse prognosis than those without (log rank=32.10, p<0.001). Multivariate analysis showed Level of Pcv-aCO₂ was an independent risk factor for 28-day mortality (HR: 3.10, 95% CI: 1.43-6.74, p=0.004). The area under the receiver operating characteristic curve of Pcv-aCO₂ for prediction of 28-day mortality in patients with BSI was 0.794. Pcv-aCO₂>6 mmHg had 81.1% sensitivity and 78.8% specificity for predicting 28-day mortality.Conclusion: Pcv-aCO₂ may be a simple and valuable biomarker to assessment of 28-day mortality in patients with BSI.     

Evaluation of matrix-assisted laser desorption ionization-time-of-flight mass spectrometry in comparison to rpoB gene sequencing for species identification of bloodstream infection staphylococcal isolates

As a result of variable expression of biochemical characters, misidentification by conventional phenotypic means often occurs with clinical isolates belonging to Staphylococcus species. Therefore, we evaluated the use of matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) for the identification of 450 blood isolates of the most relevant staphylococcal species, using sequence analysis of the rpoB gene as the reference method. A correct species identification by MALDI-TOF was obtained in 99.3% (447/450), with only three isolates being misidentified. In addition, MALDI-TOF correctly identified all the staphylococcal subspecies studied, including Staphylococcus capitis subsp. capitis and subsp. urealyticus, Staphylococcus cohnii subsp. urealyticus, Staphylococcus hominis subsp. novobiosepticus and subsp. hominis, Staphylococcus saprophyticus subsp. saprophyticus, Staphylococcus schleiferi subsp. schleiferi and Staphylococcus sciurisubsp. sciuri. Thus, MALDI-TOF MS-based species identification of staphylococci can be routinely achieved without any substantial costs for consumables or the time needed for labour-intensive DNA sequence analysis.     

Population-based burden of bloodstream infections in Finland

Bloodstream infections (BSI) are a major cause of mortality, morbidity and medical cost, but few population-based studies have concomitantly evaluated BSI incidence and mortality. Data on BSI episodes reported to national, population-based surveillance by all clinical microbiology laboratories in Finland during 2004–07 were linked to vital statistics. Age-, sex and microbe-specific incidence and mortality rates were calculated. During 2004–07, 33 473 BSI episodes were identified; BSI incidence increased from 147 to 168 per 100 000 population (average annual increase, 4.4%; p <0.001). Rates were highest among persons ≥65 years and <1 year, and higher among male patients than female patients (166 versus 152 per 100 000). The most common aetiologies were Escherichia coli (27%) and Staphylococcus aureus (13%). Among male patients, 52% of BSI were caused by gram-positive bacteria compared with 42% among female patients (p <0.001). The overall 30-day case-fatality was 13%. Of the deaths, 32% occurred within 2 days, 70% were among people aged 65 years or more and 33% were caused by E. coli or S. aureus infections. The BSI mortality rate increased from 19 to 22 per 100 000 (average annual increase: 4.0%, p 0.01). Among people aged 25 years or more, the mortality rate was 1.4-fold higher in men than women (34 versus 25 per 100 000 population). Overall excess annual mortality from BSI in the population was 18 per 100 000. The substantial BSI burden among the elderly and among adult men highlights the need for developing and implementing effective interventions, particularly for BSI caused by E. coli and S. aureus. One-third of BSI deaths occurred early, emphasizing the importance of early identification and treatment.     

Predictive factors for mortality in patients with methicillin-resistant Staphylococcus aureus bloodstream infection: impact on outcome of host,microorganism and therapy

Mortality related to methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infection (BSI) remains high, despite changes in the epidemiology. To analyze the current predictive factors for mortality we conducted a prospective study in a large cohort of patients with MRSA-BSI from 21 Spanish hospitals. Epidemiology, clinical data, therapy and outcome were recorded. All MRSAstrains were analysed, including susceptibility to antibiotics and molecular characterization. Vancomycin MICs (V-MIC) were tested by the E-test and microdilution methods. Time until death was the dependent variable in a Cox regression analysis. Overall, 579 episodes were included. Acquisition was nosocomial in 59% and vascular catheter was the most frequent source (38%). A dominant PFGE genotype was found in 368 (67%) isolates, which belonged to Clonal Complex (CC)5 and carried SCCmecIV and agr2. Microdilution V-MIC50 and V-MIC90 were 0.7 and 1.0 mg/L, respectively. Initial therapy was appropriate in 66% of episodes. Overall mortality was observed in 179 (32%) episodes. The Cox-regression analysis identified age >70 years (HR 1.88), previous fatal disease (HR 2.16), Pitt score >1 (HR 3.45), high-risk source (HR 1.85) and inappropriate initial treatment (HR 1.39) as independent predictive factors for mortality. CC5 and CC22 (HR 0.52 and 0.45) were associated with significantly lower mortality rates than CC8. V-MIC ≥ 1.5 did not have a significant impact on mortality, regardless of the method used to assess it.     

Changing aetiology,clinical features,antimicrobial resistance,and outcomes of bloodstream infection in neutropenic cancer patients

Recent changes in the management of patients with haematological malignancies might have influenced the aetiology, characteristics, antimicrobial resistance and outcomes of bloodstream infection (BSI) during neutropenia. We compared 272 episodes of BSI in adult neutropenic patients with cancer prospectively collected from January 1991 to December 1996 (first period), when quinolone prophylaxis was used, with 283 episodes recorded from January 2006 to March 2010 (second period), when antibacterial prophylaxis was stopped. Patients in the second period were significantly older and were more likely to have graft-versus-host disease and a urinary catheter in place, whereas the presence of a central venous catheter, parenteral nutrition, corticosteroids and antifungal and quinolone prophylaxis, were more frequent in the first period. More patients in the first period had mucositis and soft-tissue infection as the origin of BSI, but an endogenous source was more common during the second. Gram-positive BSI was more frequent in the first period (64% versus 41%; p <0.001), mainly due to coagulase-negative staphylococci and viridans group streptococci. In the second period gram-negative BSI increased (28% versus 49%; p <0.001), quinolone susceptibilities were recovered, but multidrug-resistant gram-negative BSI also increased (1% versus 6%; p <0.001). Although patients in the second period were more likely to need admission to the intensive-care unit, overall case-fatality rate was similar in the two periods (19% versus 15%). The aetiology of BSI in neutropenic patients with cancer has shifted from gram-positive to gram-negative organisms. Multidrug resistance among gram-negative bacilli is emerging as a therapeutic challenge. Overall case-fatality rate remains high.     

Monoclonal outbreak of Ralstonia solanacearum catheter-related bloodstream infection associated with contaminated package of normal saline solution in a tertiary care hospital

Background/aim Ralstonia solanacearum is a very rare cause of infection in humans. There is no described nosocomial outbreak due to R. solanacearum so far. We determined R. solanacearum as the source of catheter-related bloodstream infection (CRBSI) outbreak.Materials and methods This outbreak analysis was carried out in a 1000-bed tertiary care university hospital in Turkey. The outbreak analysis included hematology, oncology, nephrology, gastroenterology wards, emergency department, and intensive care units. The first case with R. solanacearum CRBSI was detected on May 20, 2019 and R. solanacearum was isolated in catheter blood cultures in 34 patients until October 3, 2019Results Standard outbreak analysis procedures were applied. Culture samples were taken from the fluids administered via catheters. The cultures did not yield any bacteria. As a result of the investigation in storage area, it was found that there were leaks, air bubbles, and water drops inside the packaging of saline solutions. R. solanacearum was yielded in the cultures obtained from the surface of saline bags and the inner sides of plastic packings. To validate our hypothesis, a clonal analysis was performed using arbitrarily primed-PCR method and Sanger sequencing of the 16S rRNA gene for identification among isolates. All R. solanacearum isolates were monoclonal and identical.ConclusionThis is the first outbreak of R. solanacearum CRBSI described in a hospital setting. The source of the outbreak was a contamination in the surface of saline bags and the inner sides of plastic packings. Efficacy of an active surveillance system, accurate and rapid conduction of microbiological identification are essential for outbreak management.     

A multicentre analysis of epidemiology of the nosocomial bloodstream infections in Japanese university hospitals

Nosocomial bloodstream infections (BSIs) are an important cause of morbidity and mortality. The current study analysed data from a concurrent surveillance programme to examine the current epidemiological trends for nosocomial BSIs at 22 Japanese university hospitals from 1 April 2008 to 31 March 2012. The number of blood culture sets taken, the rate of multiple blood culture sets and the rates of antibiotic-resistant isolates among six major nosocomial BSI pathogens (Staphylococcus aureus, Enterococcus spp., Escherichia coli, Klebsiella spp., Pseudomonas aeruginosa, and Candida spp.) not including coagulase-negative staphylococci, were evaluated. The clinical characteristics of nosocomial BSIs caused by these pathogens were also collected for 2941 patients. The number of blood culture sets taken per bed increased during the 4-year study period (from 4.07 in 2008 to 5.37 in 2011), and the rates of multiple blood culture sets also increased (from 29.9% in 2008 to 50.0% in 2011). Methicillin resistance was detected in 50.2% of S. aureus isolates. The prevalence rates of extendedspectrum beta-lactamase-producing E. coli and Klebsiella spp. isolates increased annually during the study period, and the average prevalence rates were 12.3% and 5.8%, respectively. The overall crude mortality of nosocomial BSIs due to the six pathogens evaluated was 24.5% (43.2% in ICU settings and 20.5% in non-ICU settings). Thus, our multicentre study evaluated the current epidemiological trends for nosocomial BSIs, and we found that further efforts are needed to increase the use of multiple blood culture sets and improve the prognosis of nosocomial BSIs in Japanese university hospitals.     

Predictive scoring model of mortality in Gram-negative bloodstream infection

Mortality is a well-recognized complication of Gram-negative bloodstream infection (BSI). The aim of this study was to develop a model to predict mortality in patients with Gram-negative BSI by using the Pitt bacteraemia score (PBS) and other clinical and laboratory variables. A cohort of 683 unique adult patients who were followed for at least 28 days after admission to Mayo Clinic Hospitals with Gram-negative BSI from 1 January 2001 to 31 October 2006 and who received clinically predefined appropriate empirical antimicrobial therapy was retrospectively identified. Multivariable logistic regression was used to identify independent risk factors for 28-day all-cause mortality. Regression coefficients from a multivariable model were used to develop a risk score to predict mortality following Gram-negative BSI. Malignancy (OR 3.48, 95% CI 1.94–6.22), liver cirrhosis (OR 5.42, 95% CI 2.52–11.65), source of BSI other than urinary tract or central venous catheter infection (OR 5.54, 95% CI 2.42–12.69), and PBS (OR 1.98, 95% CI 0.92–4.25 for PBS of 2–3 and OR 6.42, 95% CI 3.11–13.24 for PBS ≥ 4) were identified as independent risk factors for 28-day mortality in patients with Gram-negative BSI. A risk-score model was created by adding points for each independent risk factor, and had a c-statistic of 0.84. Patients with risk scores of 0, 4, 8, 12 and 16 had estimated 28-day mortality rates of approximately 0%, 3%, 14%, 45%, and 81%, respectively. The Gram-negative BSI risk score described herein estimated mortality risk with high discrimination in patients with Gram-negative BSI who received clinically adequate empirical antimicrobial therapy.     

Treatment duration for Escherichia coli bloodstream infection and outcomes: retrospective single-centre study

ObjectivesTo investigate the impact of treatment duration on mortality and on relapse in patients with Escherichia coli bloodstream infection (BSI).MethodsRetrospective single-centre study of patients diagnosed with E. coli BSI at our centre over a 4-year period. Exclusion criteria: age <18 years, clinical data not available, polymicrobial BSI, failure to receive in vitro active therapy, and death while receiving antibiotic therapy. Exposure variable was treatment duration dichotomized into short (≤10 days) and long (>10 days) therapy. Primary end point was all-cause mortality within 90 days after index BSI. Secondary end point was relapse, defined as repeat isolation of E. coli from blood cultures within 90 days after index BSI, in patients with documented clinical cure and completion of therapy for the initial episode.ResultsOf the 856 analysed patients: 426 received short and 430 received long therapy. All-cause mortality at day 90 occurred in 47 patients; on multivariate analysis, short therapy was not associated with a higher risk of mortality, also after adjusting the model for the propensity score of receiving short therapy. Relapse occurred in 42 patients. Independent risk factors for relapse using death as competing risk were immunosuppression (subhazard ratio 4.67, p < 0.001), and end-stage liver disease (subhazard ratio 2.58, p 0.013). The propensity-weighted estimation of the average treatment effect for relapse reduction with long therapy (>10 days) was –1.6% (p 0.26) in the total population, and –7.1% (p 0.18) in immunocompromised patients.ConclusionsWe could not identify shorter treatment duration as a risk factor for mortality and for relapse in patients with E. coli BSI.     

Cholinergic stimulation of the immune system protects against lethal infection by Salmonella enterica serovar Typhimurium

The cholinergic nervous system has been demonstrated to attenuate the inflammatory response during sepsis via the inhibitory action of acetylcholine (ACh) on macrophages. These findings were largely based on experimental sepsis models using endotoxin as the inducing agent. Herein, however, we report that the specific inhibition of acetylcholinesterase (AChE) renders animals more resistant to infection by a virulent strain of Salmonella enterica serovar Typhimurium, a Gram‐negative enteric pathogen. Inhibition of AChE was induced by a subchronic exposure to paraoxon, a potent anti‐cholinesterase metabolite of the organophosphorous compound parathion. Our findings indicate that inhibition of AChE enhanced survival of infected mice in a dose‐dependent fashion and this correlated with efficient control of bacterial proliferation in target organs. Immunologically, inhibition of AChE enabled the animals to mount a more effective inflammatory anti‐microbial response, and to secrete higher levels of interleukin‐12, a key T helper type 1‐promoting cytokine. The ACh‐induced enhancement in resistance to infection was abrogated by co‐administration of an oxime which can reactivate AChE. Hence, in a model of Gram‐negative bacterial infection, cholinergic stimulation is shown to enhance the anti‐microbial immune response leading to effective control of bacterial proliferation and enhanced animal survival.     

Unique blood culture for diagnosis of bloodstream infections in emergency departments: a prospective multicentre study

Detection of microorganisms by blood cultures (BCs) is essential in managing patients with bacteraemia. Rather than the number of punctures, the volume of blood drawn is considered paramount in efficient and reliable detection of microorganisms. We performed a 1-year prospective multicentre study in adult emergency departments of three French university hospitals comparing two methods for BCs: a unique blood culture (UBC) collecting a large volume of blood (40 mL) and the standard method of multiple blood cultures (MBC). The performances of both methods for bacterial contamination and efficient microbial detection were compared, each patient serving as his own control. Amongst the 2314 patients included, three hundred were positive for pathogens (n = 245) or contaminants (n = 55). Out of the 245 patients, 11 were positive for pathogens by UBC but negative by MBC and seven negative by UBC but positive by MBC (p 0.480). In the subgroup of 137 patients with only two BCs, UBC was superior to MBC (p 0.044). Seven and 17 patients had contaminated BCs by UBC and MBC only, respectively (p 0.062). Considering the sums of pathogens missed and contaminants, UBC significantly outperformed MBC (p 0.045). Considering the complete picture of cost savings, efficient detection of microorganisms and decrease in contaminations, UBC offers an interesting alternative to MBC.     

Blood culture gram stain,acridine orange stain and direct sensitivity-based antimicrobial therapy of bloodstream infection in patients with trauma

Purpose: The purpose of this study was to ascertain if the simple practice of Gram stain, acridine orange stain and direct sensitivity determination of positive blood culture bottles could be used to guide early and appropriate treatment in trauma patients with clinical suspicion of sepsis. The study also aimed to evaluate the error in interpreting antimicrobial sensitivity by direct method when compared to standard method and find out if specific antibiotic–organism combination had more discrepancies. Findings from consecutive episodes of blood stream infection at an Apex Trauma centre over a 12-month period are summarized. Materials and Methods: A total of 509 consecutive positive blood cultures were subjected to Gram staining. AO staining was done in BacT/ALERT-positive Gram-stain negative blood cultures. Direct sensitivity was performed from 369 blood culture broths, showing single type of growth in Gram and acridine orange staining. Results of direct sensitivity were compared to conventional sensitivity for errors. Results: No ‘very major’ discrepancy was found in this study. About 5.2 and 1.8% minor error rates were noted in gram-positive and gram-negative bacteria, respectively, while comparing the two methods. Most of the discrepancies in gram-negative bacteria were noted in β lactam – β lactamase inhibitor combinations. Direct sensitivity testing was not reliable for reporting of methicillin and vancomycin resistance in Staphylococci. Conclusions: Gram stain result together with direct sensitivity testing is required for optimizing initial antimicrobial therapy in trauma patients with clinical suspicion of sepsis. Gram staining and AO staining proved particularly helpful in the early detection of candidaemia.     

Inpatient costs,mortality and 30-day re-admission in patients with central-line-associated bloodstream infections

Previous work has suggested that central-line-associated bloodstream infection (CLABSI) is associated with increased costs and risk of mortality; however, no studies have looked at both total and variable costs, and information on outcomes outside of the intensive-care unit (ICU) is sparse. The aim of this study was to determine the excess in-hospital mortality and costs attributable to CLABSI in ICU and non-ICU patients. We conducted a retrospective cohort and cost-of-illness study from the hospital perspective of 398 patients at a tertiary-care academic medical centre from 1 January 2008 to 31 December 2010. All CLABSI patients and a simple random sample drawn from a list of all central lines inserted during the study period were included. Generalized linear models with log link and gamma distribution were used to model costs as a function of CLABSI and important covariates. Costs were adjusted to 2010 US dollars by use of the personal consumption expenditures for medical care index. We used multivariable logistic regression to identify independent predictors of in-hospital mortality. Among both ICU and non-ICU patients, adjusted variable costs for patients with CLABSI were c. $32 000 (2010 US dollars) higher on average than for patients without CLABSI. After we controlled for severity of illness and other healthcare-associated infections, CLABSI was associated with a 2.27-fold (95% CI 1.15–4.46) increased risk of mortality. Other healthcare-associated infections were also significantly associated with greater costs and mortality. Overall, CLABSI was associated with significantly higher adjusted in-hospital mortality and total and variable costs than those for patients without CLABSI.     

External validation of bloodstream infection mortality risk score in a population-based cohort

A risk score was recently derived to predict mortality in adult patients with Gram-negative bloodstream infection (BSI). The aim of this study was to provide external validation of the BSI mortality risk score (BSIMRS) in a population-based cohort. All residents of Olmsted County, Minnesota, with Escherichia coli and Pseudomonas aeruginosa BSI from 1 January 1998 to 31 December 2007 were identified. Logistic regression was used to examine the association between BSIMRS and mortality. Area under receiver operating characteristic curve (AUC) was calculated to quantify the discriminative ability of the BSIMRS to predict a variety of short-term and long-term outcomes. Overall, 424 unique Olmsted County residents with first episodes of E. coli and P. aeruginosa BSI were included in the study. Median age was 68 (range 0–99) years, 280 (66%) were women, 61 (14%) had cancer and 9 (2%) had liver cirrhosis. The BSIMRS was associated with 28-day mortality (p <0.001) with an AUC of 0.86. There was an almost 56% increase in 28-day mortality for each point increase in BSIMRS (OR 1.56, 95% CI 1.40–1.78). A BSIMRS ≥5 had a sensitivity of 74% and a specificity of 87% to predict 28-day mortality with a negative predictive value of 97%. The BSIMRS had AUC of 0.85, 0.85 and 0.81 for 7-, 14- and 365-day mortality, respectively. BSIMRS stratified mortality with high discrimination in a population-based cohort that included patients of all age groups who had a relatively low prevalence of cancer and liver cirrhosis.     

WU polyomavirus infection among children in South China

This study aimed at investigating the prevalence and clinical characteristics of children with respiratory infection by WU polyomavirus (WUPyV) in Southern China. Nasopharyngeal aspirate samples were collected from 771 children with acute respiratory tract infection admitted to hospital and 82 samples from healthy subjects for routine examination at the outpatient service at the Second Affiliated Hospital of Shantou University, Medical College from July 2008 to June 2009. WUPyV was detected by the polymerase chain reaction (PCR) and DNA sequencing. All WUPyV‐positive specimens were characterized further for nine viruses causing common respiratory infections, including in?uenza A and B, respiratory syncytial virus (RSV), parainfluenza virus (PIV) 1 and 3, human metapneumovirus, human bocavirus, adenovirus, and rhinovirus by PCR or real time (RT)‐PCR. Fifteen out of 771 specimens from patients with acute respiratory tract infection, but none from healthy subjects, were positive for WUPyV and the positivity rate was 2%. Patients with WUPyV infection were between 2 and 48 months of age, and nine of the patients were male while six female. Four out of 15 patients were co‐infected with RSV, one with adenovirus or rhinovirus, respectively. Patients with WUPyV infection displayed predominantly cough, moderate fever, and wheezing, and were diagnosed with pneumonia (n = 8), bronchiolitis (n = 4), upper respiratory tract infections (n = 2) and bronchitis (n = 1). One patient developed encephalitis. Therefore, WUPyV infection can cause acute respiratory tract infection with atypical symptoms, including severe complications, in children. J. Med. Virol. 83:1440–1445, 2011. © 2011 Wiley‐Liss, Inc.