Risk Factors For Bloodstream Infections Research Articles

In-Hospital Surgery as a Risk Factor for Onset of AmpC-Producing Escherichia coli Blood Stream Infections

There has been a progressive rise in the incidence of blood stream infections (BSI) caused by multidrug-resistant Gram-negative organisms (MDR GN), which cause increased morbidity and mortality. For this reason, recent studies have focused on risk factors of acquisition of carbapenemase-producing Enterobacteriaceae and extended-spectrum beta-lactamase producers. However, there is limited data on risk factors for BSI caused by AmpC-producing Enterobacteriaceae (AmpC EC), especially in low prevalence settings such as Australia. This study was performed to identify risk factors for acquisition of AmpC E. coli, using a retrospective matched case control design over a 3-year period. Patients with BSI caused by AmpC E. coli were matched with controls (third generation cephalosporin susceptible E. coli) by age and site of infection (n = 21). There was no significant difference in age, sex, clinical outcome, time to onset of BSI, recent antibiotic use (last 3 months), comorbidities (type 2 diabetes mellitus, renal failure) intensive care unit admission, underlying hematological condition, immunosuppressant use, APACHE II score, or any recent urological procedures (within last 3 months) between the two groups. On univariate analysis, the AmpC E. coli group were more likely to have had a surgical procedure in hospital and lived in a residential aged care facility. On multivariate logistic regression analysis, a recent surgical procedure was associated with the onset of AmpC E. coli BSI (Odd’s Ratio (OR) 4.78, p = 0.034). We concluded that in a relatively low prevalence setting such as Australia, AmpC E. coli BSI is potentially associated with surgery performed in hospital due to previous antibiotic exposure and longer hospitalization.

Temporal Dynamics and Risk Factors for Bloodstream Infection With Extended-spectrum β-Lactamase-producing Bacteria in Previously-colonized Individuals: National Population-based Cohort Study.

Little is known of the long-term risks of bloodstream infection (BSI) with extended spectrum β-lactamase-producing Enterobacteriaceae (EPE) in previously-colonized individuals. We investigated EPE-BSI risks and associated risk factors during 6 years following EPE colonization. We performed a population-based cohort study in Sweden using national health registers. Subjects were followed from their first EPE finding in feces (n = 5513) or urine (n = 17189). The effects of co-morbidity, sociodemography, and outpatient antibiotic dispensation on EPE-BSI risks were assessed. The EPE-BSI risks were compared to those of 45161 matched population-based reference subjects. The cumulative 6-year EPE-BSI incidences were 3.8%, 1.6%, and 0.02% in the urine, feces, and reference cohorts, respectively. The incidences decreased exponentially during the first 6-12 months. Among EPE-exposed subjects, urological disorders were associated with the highest adjusted cause-specific hazard ratio (aCSHR) for subsequent EPE-BSIs (3.40, 95% confidence interval 2.47-4.69). The aCSHRs were between 1.62-2.20 for male sex, immunosuppression, diabetes, malignancy, lung disease, baseline urine source, and Klebsiella pneumoniae, compared to the Escherichia coli baseline sample. Antibiotics with selective activity against gram-negative bacilli-but mostly not EPE (trimethoprim-sulfamethoxazole, fluoroquinolones, oral cephalosporins, and penicillins with extended spectrums)-and pivmecillinam were associated with doubled EPE BSI risk during the 3 months after antibiotic dispensation in EPE-colonized subjects. EPE in urine or feces is a substantial risk factor for subsequent EPE-BSIs, but the risk declines rapidly during the first year after detection. In EPE-colonized individuals, specific risk factors can be used to identify subgroups for targeted interventions, such as eradication therapy.

Risk factors for blood stream infections in multiple myeloma: A population-based study of 1154 patients in Denmark.

Multiple myeloma (MM) patients are at high risk of developing infections. The risk factors for blood stream infections (BSI) in MM patients are, however, less described. The aim of this study was to analyze the epidemiology of and risk factors for BSI in an unselected MM population. Nationwide Danish MM data of 1154 patients diagnosed from 2010 to 2013 were linked with nationwide data on blood cultures (BCs; from 2010 to 2016) to assess the peak period of having a BC taken and BC positive for pathogenic microorganisms. The highest number of BC was taken in the period from day -30 to day +180 from date of MM diagnosis. Risk factors for having a BC sampling within the peak period were as follows: immunoparesis (HR 1.5 [1.1-2.1]; P=.007), ISS-III (HR 1.3 [1.0-1.7]; P=.035), high creatinine (HR 1.4 (1.0-2.0); P=.046), and high lactate dehydrogenase (LDH) (HR 2.8 (1.6-4.7; P<.001). Risk factors for positive BC during the peak period were ISS-III (HR 2.0 (1.1-3.7); P=.023) and high LDH (HR 3.4 [1.1-10.3]; P=.028). Our results show that MM patients with aggressive disease presentation are at the highest risk of developing BSI. Furthermore, our study implies that MM is diagnosed in relation to a serious infection for a large number of patients.

Risk factors for bloodstream infections due to extended-spectrum β-lactamase producing Enterobacteriaceae in cancer patients.

Bloodstream infection (BSI) caused by Enterobacteriaceae is associated with mortality in cancer patients receiving chemotherapy. The aim of this study is to identify the risk factors and outcomes related to BSIs caused by extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae in cancer patients. Hematology/oncology patients, who were diagnosed with BSIs caused by Enterobacteriaceae by positive blood cultures were evaluated retrospectively. Patients were divided into two groups by ESBL-positive and ESBL-negative Enterobacteriaceae bacteremia. Patients' demographic features, underlying conditions, comorbidity, neutrophil count, duration of neutropenia, antibiotic use in the previous three months before infection, mechanical ventilation, steroid use, central venous catheter implementation, total parenteral nutrition (TPN), hospitalization in the past three months, stay in intensive care unit, quinolone prophylaxis, and history of infection with ESBL-producing Enterobactericeae were evaluated. Risk factors related to BSIs caused by ESBL-producing Enterobacteriaceae and mortality were assessed. A total of 122 patients were evaluated retrospectively. Quinolone propyhlaxis, TPN, infection with Extended Spectrum Beta-Lactamase positive ESBL-P Enterobacteriaceae during the previous three months, treatment with piperasillin-tazobactam or carbapenems in the previous three months were found to be independent risk factors for ESBL-P BSIs. Longer duration of neutropenia before BSI and complication at the beginning of BSI were found to be independent risk factors for mortality related to infection. ESBL-producing Enterobacteriacea should be treated with an appropriate antibiotic that is associated with better outcomes in hematology/oncology patients with BSIs. History of broad-spectrum antibiotic use and stay in hospital in the previous three months should be taken into consideration upon commencing antibiotic therapy.

Incidence of risk factors for bloodstream infections in patients with major burns receiving intensive care: A retrospective single-center cohort study

ObjectivesThe objective was primarily to identify risk factors for bloodstream infections (BSI) caused by different pathogens. MethodsA retrospective single-center cohort study was performed on 472 burn patients with an abbreviated burn severity index (ABSI)≥3, a total burn surface area (TBSA)≥10%, and an ICU stay of at least 24h. Risk factors for different BSI pathogens were analyzed by competing risks regression model of Fine and Gray. ResultsA total of 114 burn patients developed 171 episodes of BSIs caused by gram-negative bacteria (n=78;46%), gram-positive bacteria (n=69;40%), and fungi (n=24;14%) median after 14days (range, 1–164), 16days (range, 1–170), and 16days (range, 0–89), respectively. A total of 24/114 patients (21%) had fatal outcomes. Isolation of the most common bloodstream isolates Enterococcus sp. (n=26), followed by Candida sp. and Pseudomonas sp. (n=22 for both) was significantly associated with increased TBSA (p≤0.006) and ABSI (p<0.0001) and need for fasciotomy (p<0.01). The death risk of patients with MDR gram-negative bacteremia was significantly increased by a hazard ratio of 12.6 (95% CI:4.8–32.8; p<0.0001). ConclusionsA greater TBSA and ABSI were associated with a significantly higher incidence of BSIs caused by Pseudomonas sp., Enterococcus sp. and Candida sp.

Risk factors for central venous catheter‐related infections in a neonatal population – systematic review

ObjectiveThis was a systematic review of the incidence density and risk factors for central venous catheter‐related infections in a neonatal population. Data sourceThe MEDLINE, Embase, Cochrane, BDENF, SciELO, and LILACS databases were used without date or language restriction. Studies that analyzed risk factors for bloodstream infections in newborns were identified. Data synthesisA total of 134 articles were found that met the eligibility criteria. Of these articles, 14 were selected that addressed risk factors for central venous catheter‐related infection in neonates. Catheter‐related bloodstream infections remain an important complication, as shown by the incidence rates reported in the studies included in this review. The observed risk factors indicate that low birth weight, prematurity, and longer catheter permanence are related to a higher incidence of bloodstream infections. It has been observed that low rates of catheter‐related infections, i.e., close to zero, are already a reality in health institutions in developed countries, since they use infection surveillance and control programs. ConclusionCatheter‐related bloodstream infections still show high incidence density rates in developing countries. The authors emphasize the need for further longitudinal studies and the need for better strategies to prevent risk factors, aiming at the reduction of catheter‐related infections.

Risk factors for central venous catheter-related infections in a neonatal population – systematic review

ObjectiveThis was a systematic review of the incidence density and risk factors for central venous catheter-related infections in a neonatal population. Data sourceThe MEDLINE, Embase, Cochrane, BDENF, SciELO, and LILACS databases were used without date or language restriction. Studies that analyzed risk factors for bloodstream infections in newborns were identified. Data synthesisA total of 134 articles were found that met the eligibility criteria. Of these articles, 14 were selected that addressed risk factors for central venous catheter-related infection in neonates. Catheter-related bloodstream infections remain an important complication, as shown by the incidence rates reported in the studies included in this review. The observed risk factors indicate that low birth weight, prematurity, and longer catheter permanence are related to a higher incidence of bloodstream infections. It has been observed that low rates of catheter-related infections, i.e., close to zero, are already a reality in health institutions in developed countries, since they use infection surveillance and control programs. ConclusionCatheter-related bloodstream infections still show high incidence density rates in developing countries. The authors emphasize the need for further longitudinal studies and the need for better strategies to prevent risk factors, aiming at the reduction of catheter-related infections.

Extracorporeal Membrane Oxygenation–Associated Bloodstream Infections In Children

This was a case-control study of extracorporeal membrane oxygenation cases spanning 5 years. Bloodstream infection (BSI) occurred in 12/207 subjects, with Candida spp.-4, Pseudomonas spp.-2 and Staphylococcal spp.-2 being predominant. No risk factors for BSI were identified. Exposure to broad spectrum antibiotics was common in both BSI and control patients. Prophylactic antimicrobials did not decrease the risk of BSI.

Risk Factors for Bloodstream Infection in Children with Intestinal Insufficiency on Parenteral Nutrition

BackgroundBloodstream infection (BSI) is a major cause of morbidity and mortality in children with intestinal insufficiency, but studies defining risk factors are lacking. We aim to identify risk factors of BSI in children with intestinal insufficiency on parenteral nutrition (PN).MethodsRetrospective cohort study of children ≤ 18 years of age with intestinal insufficiency dependent on PN, who were followed at Lucile Packard Children’s Hospital (LPCH). The outcome of interest was rate of BSI. We studied proposed risk factors for BSI including sex, age, small intestine length at the time of surgery, diagnosis of short bowel syndrome (SBS), citrulline level (a marker of functioning enterocytes mass), central line (CL) days and CL breaks within 3 months. Data were represented in 6-monthintervals to study time dependent variables. Univariate analyses using t-test and regression analysis were conducted.ResultsRecords between 2014 and 2016 were reviewed identifying 43 children who met the inclusion criteria. The rate of infection was 3.39 per 1000 CL days. Younger age increased rate of BSI by 0.23/1000 CL days per year (95% confidence interval (CI): 0.14–0.32; P = 0.015) and shorter small bowel increased it by 0.27/1000 CL days for every 10-cm of small bowel (95% CI: 0.14–0.4; P = 0.045). Recent line breaks increased BSI rate by 3.47/1000 CL days (95% CI: 2.1–4.8; P = 0.014), and diagnosis of SBS increased it by 2.69/1000 CL days (95% CI: 2.02–3.36); P < 0.001). Rates of BSI increased by 0.33/1000 CL days for every 5 nmol/ml decrease in citrulline level, but this did not reach statistical significance (P = 0.059). We found no significant association between CVL days and the rate of BSI.ConclusionFactors associated with disturbance in intestinal integrity such as shorter small intestine and diagnosis with SBS are significant risk factors for BSI, highlighting the importance of intestinal translocation in its pathogenesis. Recent line breaks are important risk factor for BSI; an opportunity for prevention. BSI rates are higher in younger children likely due to immature bowel and/or difficult compliance with hygienic precautions handling CLs. No association was found between CL days and rate of BSI, which could guide the decision of CL removal vs. salvage.Disclosures All authors: No reported disclosures.

Outcomes and Predictive Factors Associated with Adequacy of Antimicrobial Therapy in Patients with Central Line-Associated Bloodstream Infection.

Central venous catheters are significant risk factors for bloodstream infection (BSI), which are directly associated with increased morbidity and mortality. This study was a retrospective cohort study for the time period of July 2011-June 2014 in patients with central line-associated bloodstream infection (CLABSI) to determine the microbiological profile and antimicrobial adequacy of patients with CLABSI in a tertiary hospital. One hundred and twenty-one CLABSI cases were identified. Ninety-two percent (n = 111) of patients had monomicrobial BSI. Gram-negative bacteria were the most prevalent (49%, n = 63), with Klebsiella spp. predominating (30%, n = 19). Among the Gram-positive bacteria (n = 43, 33%), coagulase-negative staphylococci was the major pathogen (58%, n = 25), and all isolates were methicillin resistant. Antimicrobial therapy was assessed as adequate in 81% (n = 98) of cases. In-hospital mortality was 36% (n = 43 cases). Our CLABSI patients had a high mortality, although antimicrobial therapy was appropriate. Gram-negative bacteria were responsible for almost half of the cases and there was a high rate of bacteria resistance to extended-spectrum antibiotics.

African American Race Is a Newly Identified Risk Factor for Postengraftment Blood Stream Infections in Pediatric Allogeneic Blood and Marrow Transplantation

Blood stream infections (BSI) are a major source of morbidity and mortality both in allogeneic blood and marrow transplant (BMT) recipients. Various risk factors for BSI in BMT have been identified. The impact of race and cytomegalovirus (CMV) viremia, a common complication after engraftment, however, has not been rigorously assessed. This is important because both CMV infection and ganciclovir, the mainstay of pre-emptive therapy, have myelosuppressive and immunosuppressive effects. We conducted a retrospective analysis to test the hypothesis that race and CMV viremia predispose allogeneic BMT patients to postengraftment BSI. We analyzed 278 allogeneic BMT performed at Children's Healthcare of Atlanta between January 1, 2005 and December 31, 2014 that met eligibility criteria. We performed a multivariate analysis to estimate the effect of CMV viremia on risk for BSI in the postengraftment period (days +30 to 100). Risk for BSI was associated with CMV viremia (hazard ratio [HR], 3.34; 95% confidence interval [CI], 1.51 to 7.36; P = .003); grade III and IV acute graft-versus-host disease (HR, 3.28; 95% CI, 1.55 to 6.92; P = .002), and African American race (HR, 2.22; 95% CI, 1.09 to 4.51; P = .027). The results of our study highlight the importance of a novel risk factor for postengraftment BSI, not previously considered—African American race.

Differential effect of prior β-lactams and fluoroquinolones on risk of bloodstream infections secondary to Pseudomonas aeruginosa

ObjectiveThis retrospective case–control study examines risk factors for bloodstream infections (BSI) due to Pseudomonas aeruginosa (PSA). MethodsHospitalized adults with Gram-negative BSI at Palmetto Health from 2010 to 2015 were identified. Multivariate logistic regression was used to examine PSA BSI risk factors. ResultsSeventy and 910 patients with PSA and Enterobacteriaceae BSI, respectively, were included. Prior use of β-lactams (adjusted odds ratio [aOR] 3.9, 95% confidence intervals [CI]: 2.3–6.9), but not fluoroquinolones (aOR 1.0, 95% CI: 0.4–2.2), was a risk factor for PSA BSI. Immune compromised status (aOR 3.7, 95% CI: 2.0–6.7), respiratory source (aOR 4.4, 95% CI: 2.1–8.9), and prolonged hospitalization (aOR 1.9, 95% CI: 1.1–3.5), were predictors of PSA BSI. ConclusionsDetermination of class of previously used antibiotics among other clinical variables helps identify patients at risk of PSA BSI and offers opportunities to optimize empirical antimicrobial therapy.

Association between chronic hemodialysis and bloodstream infections caused by chromosomally mediated AmpC-producing Enterobacteriaceae.

The combination of inherent antimicrobial resistance and high mortality after bloodstream infections (BSIs) caused by chromosomally mediated AmpC-producing Enterobacteriaceae (CAE) emphasizes the importance of identifying patients at risk of BSI because of these bacteria. This retrospective case-control study examines chronic hemodialysis among other risk factors for BSI caused by CAE. Hospitalized adults with Enterobacteriaceae BSI from January 1, 2010-June 30, 2014, at 2 large community hospitals in the Southeastern United States were identified. Multivariate logistic regression was used to examine risk factors for CAE BSI. Among 831 Enterobacteriaceae bloodstream isolates, 106 (13%) met the phenotypic definition of CAE. Enterobacter spp accounted for 47% (50/106) of CAE BSIs. Chronic hemodialysis was an independent risk factor for CAE BSI (adjusted odds ratio [aOR], 2.34; 95% confidence interval [CI], 1.21-4.44). Other predictors of CAE BSI included nosocomial acquisition (aOR, 1.72; 95% CI, 1.02-2.87) and exposure to β-lactam antibiotics within the last 30 days (aOR, 2.39; 95% CI, 1.37-4.14). To our knowledge, this is the first study to demonstrate an increased risk of CAE BSI in patients with end-stage renal disease undergoing chronic hemodialysis. This highlights the importance of effective infection prevention and antimicrobial stewardship interventions in hemodialysis clinics. Further studies to examine the impact of antibiotics on intestinal microbiota and rates of CAE colonization in this patient population are warranted.

Characteristics of Multidrug-Resistant Corynebacterium spp. Isolated from Blood Cultures of Hospitalized Patients in Japan.

Corynebacterium is a genus consisting of Gram-positive, rod-shaped bacteria, that is wildly distributed in nature. We report the epidemiological characterization of Corynebacterium spp. isolated from blood specimens at the Kurume University Hospital, between June 2008 and November 2011. Twenty-two strains that were likely Corynebacterium spp. were isolated from 22 hospitalized patients, of which 12 (54.5%) were identified as Corynebacterium striatum. Minimum inhibitory concentration tests were performed after biochemical and genotypic identifications. Biofilm production was detected using a 96-well microplate assay. The dissemination of C. striatum was investigated using pulsed-field gel electrophoresis (PFGE). All strains showed the tendency to be resistant to multiple drugs except vancomycin. Fourteen (82.4%) strains, including 9 C. striatum strains were capable of producing biofilms. Four distinct PFGE patterns were detected among C. striatum strains; 6 of which were identified as dominant pattern A (defined in this study) and had high biofilm production ability. During the 3-year monitoring period, these strains might have repeatedly infected the patients or could have readily colonized the hospital environments. C. striatum appeared to be a potential risk factor for bloodstream infections in hospitalized patients. More surveillance and enhanced control strategies are necessary to decrease Corynebacterium spp. infections in hospitals.

Fatores de risco para infecção de corrente sanguínea associada ao cateter central de inserção periférica em neonatos

Resumo Objetivo Identificar os fatores de risco para infecção de corrente sanguínea associada ao cateter central de inserção periférica em neonatos. Métodos Estudo de coorte prospectivo conduzido em unidade de terapia intensiva com recém-nascidos submetidos à instalação de 401 cateteres centrais de inserção periférica. Características clínicas do neonato, técnica de inserção do cateter, terapia intravenosa e tempo de permanência do cateter foram testados como fatores de risco para remoção por infecção de corrente sanguínea associada ao cateter, por meio de análise bivariada e análise multivariada com regressão de Poisson. Resultados Os dados sugerem que as menores médias de peso e idade gestacional corrigida, bem como o maior tempo de permanência do cateter estiveram associados à ocorrência de infecção de corrente sanguínea associada ao cateter. A menor idade gestacional corrigida, os diagnósticos clínicos de transtorno transitório do metabolismo e apneia, e o uso do cateter de duas vias foram identificados como fatores de risco. Conclusão A menor idade gestacional corrigida do neonato, os diagnósticos clínicos de transtorno transitório do metabolismo e apneia, e o uso do cateter de duas vias foram identificados como fatores de risco para infecção de corrente sanguínea associada ao cateter central de inserção periférica em neonatos.

Epidemiology and Microbiologic Characterization of Nosocomial Candidemia from a Brazilian National Surveillance Program.

Candidemia is a growing problem in hospitals all over the world. Despite advances in the medical support of critically ill patients, candidiasis leads to prolonged hospitalization, and has a crude mortality rate around 50%. We conducted a multicenter surveillance study in 16 hospitals distributed across five regions of Brazil to assess the incidence, species distribution, antifungal susceptibility, and risk factors for bloodstream infections due to Candida species. From June 2007 to March 2010, we studied a total of 2,563 nosocomial bloodstream infection (nBSI) episodes. Candida spp. was the 7th most prevalent agent. Most of the patients were male, with a median age of 56 years. A total of 64 patients (46.7%) were in the ICU when candidemia occurred. Malignancies were the most common underlying condition (32%). The crude mortality rate of candidemia during the hospital admission was 72.2%. Non-albicans species of Candida accounted for 65.7% of the 137 yeast isolates. C. albicans (34.3%), Candida parapsilosis (24.1%), Candida tropicalis (15.3%) and Candida glabrata (10.2%) were the most prevalent species. Only 47 out of 137 Candida isolates were sent to the reference laboratory for antifungal susceptibility testing. All C. albicans, C. tropicalis and C. parapsilosis isolates were susceptible to the 5 antifungal drugs tested. Among 11 C. glabrata isolates, 36% were resistant to fluconazole, and 64% SDD. All of them were susceptible to anidulafungin and amphotericin B. We observed that C. glabrata is emerging as a major player among non-albicans Candida spp. and fluconazole resistance was primarily confined to C. glabrata and C. krusei strains. Candida resistance to echinocandins and amphotericin B remains rare in Brazil.Mortality rates remain increasingly higher than that observed in the Northern Hemisphere countries, emphasizing the need for improving local practices of clinical management of candidemia, including early diagnosis, source control and precise antifungal therapy.

Bloodstream infections caused by multi-drug resistant Proteus mirabilis: Epidemiology, risk factors and impact of multi-drug resistance

ABSTRACTBackground The prevalence of antimicrobial co-resistance among ESBL-producing Enterobactereaceae is extremely high in Israel. Multidrug-resistant Proteus mirabilis strains (MDR-PM), resistant to almost all antibiotic classes have been described. The aim was to determine the risk factors for bloodstream infections caused by MDR-PM and clinical outcomes. Methods A retrospective case-control study. Adult patients with PM bacteremia during 7 years were identified retrospectively and their files reviewed for demographics, underlying diseases, Charlson Comorbidity Index, treatment and outcome. Results One hundred and eighty patients with PM-bloodstream infection (BSI) were included; 90 cases with MDR-PM and 90 controls with sensitive PM (S-PM). Compared to controls, cases more frequently were from nursing homes, had recurrent hospital admissions in the past year and received antibiotic therapy in the previous 3 months, were bedridden and suffered from peripheral vascular disease and peptic ulcer disease (p < 0.001). Two-thirds of the MDR-PM isolates were ESBL-producers vs 4.4% of S-PM isolates (p < 0.001, OR = 47.6, 95% CI = 15.9–142.6). In-hospital crude mortality rate of patients with MDR-PM BSI was 37.7% vs 23.3% in those with S-PM BSI (p = 0.0359, OR = 2, 95% CI = 1.4–3.81). Conclusions PM bacteremia in elderly and functionally-dependent patients is likely to be caused by nearly pan-resistant PM strains in the institution; 51.8% of the patients received inappropriate empiric antibiotic treatment. The crude mortality rate of patients with MDR-PM BSI was significantly higher than that of patients with S-PM BSI.

Extracorporeal Membrane Oxygenation-Associated Bloodstream Infections in Children

This was a case-control study of extracorporeal membrane oxygenation cases spanning 5 years. Bloodstream infection (BSI) occurred in 12/207 subjects, with Candida spp.-4, Pseudomonas spp.-2 and Staphylococcal spp.-2 being predominant. No risk factors for BSI were identified. Exposure to broad spectrum antibiotics was common in both BSI and control patients. Prophylactic antimicrobials did not decrease the risk of BSI.

Risk factors and prognosis of bloodstream infection in the ICU patients

Objective To investigate the risk factors and prognosis of blood stream infection in patients of intensive care unit (ICU). Methods Clinical data of all patients with culture-positive sepsis were collected from all ICUs of Guangdong General Hospital from October 12th, 2012 to December 1st, 2014 for retrospective study. Physiological characteristics and laboratory data were compared between patients with blood culture-positive sepsis group and patients without sepsis of control group. Logistic regression analysis was made to identify the risk factors for blood stream infection. Patients with blood culture-positive sepsis group were further divided into survivor and non-survivor groups according to the clinical outcomes. Physiological and laboratory data were compared between two groups. Logistic regression analysis was also performed to identify the risk factors for mortality. Results There were 299 patients with positive blood culture sepsis admitted in the ICUs in two years. Of them, 250 patients infected with Gram positive cocci including staphylococcus haemolyticus, staphylococcus epidermidis, staphylococcus capitis and staphylococcusaureus accounting for the majority. There were 174 patients infected with Gram negative bacilli including acinetobacter baumannii, Escherichia coli and Klebsiella pneumoniaesubsp. pneumoniae accounting for the majority. A univariate analysis demonstrated that there were significant differences in hypertension (P =0.001) , diabetes (P=0.01) , coronary heart diseases and heart failure (P=0.000) , chronic renal insufficiency (P=0.000) , prolonged mechanical ventilation (P=0.000) , pre-admission intravenous administration of antibiotics (P=0.000) , and hypoalbuminemia (P=0.008) between culture positive group and control group. A logistic regression analysis demonstrated that diabetes [ OR=2.158, 95% CI(1.230, 3.787) , P=0.007] , chronic renal insufficiency [ OR=13.410, 95% CI (1.715, 104.879) , P=0.013] , pre-admission intravenous administration of antibiotics [ OR=8.375, 95% CI (5.267, 13.317) , P=0.000] were independent risk factors for bloodstream infections in ICU. In patients with positive blood culture, the non-survivor group had patients with higher advance of old age, higher rate of hypertension, coronary heart diseases or congestive heart failure, tumor and chronic renal insufficiency, prolonged mechanical ventilation and higher incidence of surgery and pre-admission intravenous administration of antibiotics compared with the survivor group. The advance of old age [ OR=1.023, 95% CI (1.008-1.037) , P=0.002] , prolonged mechanical ventilation [ OR=1.055, 95% CI (1.024, 1.088) , P=0.000] and hypoalbuminemia [ OR=0.933, 95% CI (0.898, 0.971) , P=0.001] were independently associated with mortality of bloodstream infection in ICU. Conclusions Diabetes, chronic renal insufficiency and pre-admission intravenous administration of antibiotics were associated with the development of blood stream infection in ICU. The advance of old age, prolonged mechanical ventilation and hypoalbuminemia were independent risk factors for mortality in patients with culture-positive sepsis in ICU. Key words: Descriptive retrospective study; Logistic regression analysis; Blood stream infection; Culture-positive sepsis; Intensive care unit; Risk factor; Prognosis; Mortality

Multidrug-resistant Acinetobacter Baumannii infection in Intensive Care Unit: A retrospective analysis

To analyze the clinical characteristics of patients with bloodstream Acinetobacter baumannii infection in Intensive Care Unit (ICU). Eighty-three ICU patients with bloodstream Acinetobacter baumannii infection from January 2012 to March 2015 were retrospectively analyzed, including infection-related risk factors, drug-resistant bacteria, treatments and prognosis. Among 83 patients, 60 patients (72.29%) were male, 23 (27.71%) were female. The youngest patient was 40 days old, the oldest was 92 years old, the age was (46.23±19.22) years old. In total, there were 20 patients (24.10%) with plural bacterial infection in blood, 60 (72.29%) with more than 3 kinds of disorders, 52 patients suffered homologous bacterial infection in blood and other organs. Among these cases, lower respiratory tract had the highest percentage of homologous bacteria (29 cases), followed by catheter (11 cases), wound secretion (8 cases), cerebrospinal fluid (3 cases) and ascites (1 case). The risk factors of bloodstream infection by Acinetobacter baumannii included catheterization, serious primary disease and basic disease, usage of corticosteroids, surgery and invasive operation and so on. Acinetobacter baumannii were highly resistant. Most of them were multi-drug resistance, and some were pan-drug resistance. It showed more than 80% drug resistant rate to antibiotics except sulbactam, cefopcrazone and amikacin. Among 83 patients, 55 cases (66.26%) were dead, 25 cases (30.12%) were improved and 3 cases (3.62%) were cured. Acinetobacter baumannii are highly and multidrug-resistant to commonly used antibiotics. Patients in ICU suffering serious basic diseases should be shorten hospitalization time, restricted the use of breathing machine and immunosuppressant. It must carry out disinfection for invasive operation to reduce the risk of bloodstream infections, and the abuse of antibiotics must be avoided to slow bacteria resistance.