Mortality Of Bloodstream Infections Research Articles

Bloodstream infections caused by Enterococcus spp: A 10-year retrospective analysis at a tertiary hospital in China

In order to discover the risk factors for 30-day mortality in bloodstream infections (BSI) caused by Enterococcus spp. strains, we explored the clinical and therapeutic profile of patients with Enterococcus spp. BSI and the characteristics of this condition. A total of 64 patients with BSI caused by Enterococcus spp. who were treated in our hospital between 2006 and 2015 were included in the study. The clinical features of patients, microbiology, and 30-day mortality were collected from the electronic medical records database and analyzed. The results showed that there were 38 patients infected by Enterococcus faecalis (E. faecalis), 24 by Enterococcus faecium (E. faecium), 1 by Enterococcus casseliflavus (E. casseliflavus), and 1 by Enterococcus gallinarum (E. gallinarum). A Charlson comorbidity score ≥5, corticosteroid treatment, placement of catheters or other prosthetic devices and history of antibiotic use were found more frequently in E. faecium BSI patients than in E. faecalis patients (P=0.017, P=0.027, P=0.008 and P=0.027, respectively). Furthermore, the univariate and multivariate analysis showed that corticosteroid treatment (OR=17.385, P=0.008), hospital acquisition (OR=16.328, P=0.038), and vascular catheter infection (OR=14.788, P=0.025) were all independently associated with 30-day mortality. Our results indicate that E. faecalis and E. faecium are two different pathogens with unique microbiologic characteristics, which cause different clinical features in BSI, and the empiric antimicrobial treatments are paramount for patients with enterococcal BSI.

The Use of Bloodstream Infection Mortality to Measure the Impact of Antimicrobial Stewardship Interventions: Assessing the Evidence

This review sets out to evaluate the current evidence on the impact of inappropriate therapy on bloodstream infections (BSI) and associated mortality. Based on the premise that better prescribing practices should result in better patient outcomes, BSI mortality may be a useful metric to evaluate antimicrobial stewardship (AMS) interventions. A systematic search was performed in key medical databases to identify papers published in English between 2005 and 2015 that examined the association between inappropriate prescribing and BSI mortality in adult patients. Only studies that included BSIs caused by ESKAPE (Enterococcus faecium/faecalis, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter species) organisms were included. Study quality was assessed using the GRADE criteria and results combined using a narrative synthesis. We included 46 studies. Inappropriate prescribing was associated with an overall increase in mortality in BSI. In BSI caused by resistant gram positive organisms, such as methicillin resistant S. aureus, inappropriate therapy resulted in up to a 3-fold increase in mortality. In BSI caused by gram negative (GN) resistant organisms a much greater impact ranging from 3 to 25 fold increase in the risk of mortality was observed. While the overall quality of the studies is limited by design and the variation in the definition of appropriate prescribing, there appears to be some evidence to suggest that inappropriate prescribing leads to increased mortality in patients due to GN BSI. The highest impact of inappropriate prescribing was seen in patients with GN BSI, which may be a useful metric to monitor the impact of AMS interventions.

Burden of bloodstream infection in an area of Mid-Norway 2002-2013: a prospective population-based observational study

BackgroundStudies from several countries indicate that the incidence and mortality of bloodstream infection (BSI) have been increasing over time.MethodsWe studied the burden of disease and death related to BSI in a defined geographical area of Mid-Norway, where BSI episodes were prospectively recorded by the same microbiological department during 12 consecutive years. Death from BSI was defined as death within 30 days of BSI detection. Age and sex standardized incidence and mortality rates and case fatality rates were calculated.ResultsBetween 2002 and 2013, 1995 episodes of BSI in 1719 patients aged 16 to 99 years were included. The overall incidence of BSI was 215 per 100,000 person-years. The incidence increased exponentially with age, particularly in males. The incidence increased from 205 to 223 per 100,000 person-years from 2002–07 to 2008–13. Escherichia coli was the most frequently isolated infective agent, followed by Streptococcus pneumoniae and Staphylococcus aureus. The rate of S. pneumoniae BSI decreased over time in males (on average by 9.2% annually), but not in females. The total rate of BSI microbes with acquired resistance increased slightly over time, but did not exceed 2 episodes per 100,000 person-years. The mortality of BSI was 32 per 100,000 person-years, higher in males than in females (36 vs. 28 per 100,000 person-years) and was significantly higher in old age, particularly in males. The total BSI mortality was similar in the first and second halves of the study period, but the mortality of S. pneumoniae BSI decreased in males (15.0% annually). The crude case fatality decreased from the first to the second half of the study period (17.2% to 13.1%; p = 0.014). The rate of blood culture sampling increased more than twofold during the study period.ConclusionsThe mortality of BSI remained stable during 2002–2013. At the same time, BSI incidence increased and case fatality rate decreased, perhaps because an increased rate of blood culture sampling may have led to improved detection of milder BSI episodes. Very low, yet slightly increasing rates of microbes with acquired resistance were observed.

Escherichia coli ST131 is Associated With Increased Mortality In Bloodstream Infections From Urinary Tract Source

Escherichia coli ST131 is Associated With Increased Mortality In Bloodstream Infections From Urinary Tract Source

Clinical and Mortality Risk Factors in Bloodstream Infections with Carbapenem-Resistant Enterobacteriaceae.

Objective To investigate the risk factors underlying the occurrence and mortality of bloodstream infections (BSIs) with carbapenem-resistant Enterobacteriaceae (CRE). Methods Medical information was retrospectively analyzed from 148 cases of patients with Enterobacteriaceae BSIs at a medical center in China, between 2013 and 2015. Results The 30-day mortality rate in the CRE group was 65.4%. Indwelling urethral catheterization, admission to the ICU, use of antibiotics within 30 days, and BSIs from the respiratory system were associated with CRE BSIs. Lung infection, abdominal infection, central venous catheterization, and use of hormones within 30 days were associated with mortality. Conclusion The 30-day mortality rate of CRE BSIs was high. Lung infections, abdominal infections, central venous catheterization, and use of hormones within 30 days increased the mortality rate of Enterobacteriaceae BSIs.

Outcome of bloodstream infections among spinal cord injury patients and impact of multidrug-resistant organisms.

Retrospective cohort study. Our study aimed to describe the outcome of bloodstream infection (BSI) in spinal cord injury (SCI) patients and their associated risk factors for severity and mortality. A French University Hospital. We conducted a retrospective cohort study of all BSIs occurring in hospitalized SCI patients. We analyzed their outcome and risk factors especially the impact of multidrug-resistant organisms (MDROs). Overall, 318 BSIs occurring among 256 patients were included in the analysis. Mean age was 50.8 years and gender ratio (M/F) was 2.70, with a mean injury duration of 11.6 years.Severity and 30-day mortality of BSI episodes were, respectively, 43.4% and 7.9%. BSI severity was significantly more frequent when caused by respiratory tract infections (RTIs) (odds ratio (OR)=1.38; 95% confidence interval (CI): 1.13-1.44) and significantly lower when caused by urinary tract infections (UTIs) (OR=0.47; 95% CI: 0.28-0.76). BSI mortality was significantly higher when caused by RTIs (OR=3.08; 95% CI: 1.05-8.99), catheter-related bloodstream infections (OR=3.54; 95% CI: 1.36-9.18) or Pseudomonas aeruginosa infections (OR=3.79; 95% CI: 1.14-12.55).MDROs were responsible for 41.2% of all BSI. They have no impact on severity and mortality, whichever be the primary site of infection.In multivariate analysis, mortality was higher when BSI episodes were due to RTIs (OR=3.26; 95% CI: 1.29-8.22) and Pseudomonas aeruginosa infections (OR=3.53; 95% CI: 1.06-11.70), or when associated with immunosuppressive therapy (OR=2.57; 95% CI: 1.14-5.78) or initial severity signs (OR=1.68; 95% CI: 1.01-2.81). BSI occurring in SCI population were often severe but mortality remained low. MDROs were frequent but not associated with severity or mortality of BSI episodes. Risk factors associated with mortality were initial severe presentation, RTI, immunosuppressive therapy and BSI due to Pseudomonas aeruginosa.

Predictors of mortality in bloodstream infections caused by multidrug-resistant gram-negative bacteria: 4 years of collection.

The study was undertaken to describe the profile of patients and the characteristics of all multidrug-resistant gram-negative bacteria (MDR-GNB) and to assess mortality. We examined 138 patients with bloodstream infections (BSIs) caused by MDR-GNB. Clinical characteristics, antibiotic therapy, and in-hospital mortality were analyzed. Survivor and nonsurvivor subgroups were compared to identify predictors of mortality. The in-hospital mortality rate was 25.4%. Univariate analysis revealed that comorbidities and inadequate initial antimicrobial treatment could increase risk of death. In Cox regression analysis, mortality was independently associated with the age (P = .034), hospitalization in an intensive care unit (ICU) (P = .04), invasive procedures (P < .001), and Acute Physiology and Chronic Health Evaluation II scores (P < .001), whereas combination therapy or monotherapy was not associated with mortality (P = .829). Postantibiogram therapy was associated with hospitalization in an ICU (P = .006), Charlson comorbidity index score (P = .003), and inadequate initial antimicrobial treatment (P < .001). MDR-GNB strains and antimicrobial regimens were not the major risk factors of mortality. Inadequate initial antimicrobial treatment, invasive procedures, high Acute Physiology And Chronic Health Evaluation II scores, hospitalization in an ICU, and comorbidities were the important factors responsible for mortality. Although there was no difference between combination therapy and monotherapy in mortality, combined treatment may be more effective than monotherapy for patients in an ICU, with a Charlson comorbidity index score < 4, or inadequate initial antimicrobial treatment.

Association between inappropriate empirical antimicrobial therapy and hospital length of stay in Gram-negative bloodstream infections: stratification by prognosis.

The potential benefit from appropriate empirical antimicrobial therapy in patients with favourable prognosis at initial presentation with Gram-negative bloodstream infection (BSI) remains unclear. This retrospective cohort study examined the impact of inappropriate empirical antimicrobial therapy on hospital length of stay (HLOS) following Gram-negative BSI after stratification by predicted prognosis using the BSI mortality risk score (BSIMRS). Hospitalized adults with first episodes of Gram-negative BSI from 1 January 2010 to 31 December 2013 at Palmetto Health Hospitals in Columbia, SC, USA were identified. Multivariate Cox proportional hazards regression was used to examine the association between inappropriate empirical antimicrobial therapy and HLOS overall and within each predefined BSIMRS category (<5 and ≥5). Among 830 unique patients with Gram-negative BSI, 469 and 361 had BSIMRS <5 and ≥5, respectively. Overall, the median age was 65 years, 448 (54%) were women, Escherichia coli (444; 53%) was the most common bloodstream isolate and 444 (53%) had a urinary source of infection. After adjustments in the multivariate model, BSIMRS (HR = 1.14 per point, 95% CI = 1.11-1.17, P < 0.001) and inappropriate empirical antimicrobial therapy (HR = 1.41, 95% CI = 1.07-1.91, P = 0.01) were independently associated with increased risk of remaining hospitalized following Gram-negative BSI. Median HLOS with appropriate and inappropriate empirical antimicrobial therapy was 7 and 10 days, respectively, in patients with BSIMRS <5 (P = 0.03) and 13 and 17 days, respectively, in those with BSIMRS ≥5 (P = 0.02). Inappropriate empirical antimicrobial therapy is associated with prolonged HLOS following Gram-negative BSI in patients with both good and guarded prognosis.

An analysis of 181 cases with blood stream infection caused by Streptococcus agalactiae in children from 2011 to 2015: a multi-center retrospective study

To analyze the clinical characteristics of blood stream infection caused by Streptococcus agalactiae in children and the drug-resistance of the isolates. All cases with Streptococcus agalactiae growth in blood or cerebrospinal fluid cultures from January 1, 2011 to December 31, 2015 were enrolled by checking the laboratory information system (LIS) from 7 Class 3 Grade A hospitals (4 in Zhejiang, 2 in Shanghai and 1 in Chongqing). Clinical data were collected for analysis. χ(2) test, t test and non parametric test were used in the study. One hundred and eighty-one pediatric cases of blood stream infection caused by Streptococcus agalactiae were included in current study. Eighty-six cases (47.5%) were male, and with age range from one day to 9 years (media 13 days). Thirty cases (16.6%) were premature infants and 127 cases (70.2%) were born via vaginal delivery. Seventy-one cases (39.2%) had early onset (<7 d) infections, and 106 cases (58.6%) had late onset (7-89 d) infections. Seventy-eight cases (43.1%) were complicated with purulent meningitis. Incidences of vaginal delivery(81.7%(58/71) vs. 62.3%(66/106)), shortness of breath moaning (43.7%(31/71) vs. 15.1%(16/106)) and preterm premature rupture of membranes (25.4%(18/71) vs. 3.8%(4/106)) were higher in the early onset infection group compared with the late onset group(P all<0.05). However, the number of cases who had fever(25.4%(18/71)vs.85.8%(91/106)) and complicated with purulent meningitis (29.6%(21/71) vs. 53.8%(57/106)) in early onset infections group was less than that in the late onset group(P both<0.05). The blood cultures of most patients (87.8%) were performed before the use of antibiotics. Drug-resistant tests showed that the sensitive rates to penicillin G, ceftriaxone and cefotaxime were 98.9%, 99.0% and 99.0% respectively. All strains were sensitive to vancomucine. The rates of resistance to clindamycin and erythromycin were 68.0% and 34.0%, respectively. Only 39 cases (22.0%) were treated with single antibiotics of either penicillins or cephalosporins, 80 cases (45.2%) were treated with antibiotics containing β lactamase inhibitor, 61 cases (34.5%) were treated with either meropenem or cefoperazone-sulbactam. One hundred and fifty-four cases were cured, while 19 died (including 13 complicated with purulent meningitis) and 8 lost to follow up after giving up of treatment. The incidence and mortality of blood stream infection caused by Streptococcus agalactiae complicated with purulent meningitis are high in children. Penicillin is the first choice in treatment. Antibiotics should be selected accorrding to the drug-resistance test.

Low-Dose Acetylsalicylic Acid Treatment and Impact on Short-Term Mortality in Staphylococcus aureus Bloodstream Infection: A Propensity Score-Matched Cohort Study.

Staphylococcus aureus bloodstream infection is associated with considerable mortality. Experimental models suggest a direct antistaphylococcal effect of acetylsalicylic acid, but evidence from human studies is scarce. We aimed to estimate the effect of low-dose acetylsalicylic acid therapy on mortality in bloodstream infections caused by S. aureus compared with Escherichia coli. Retrospective cohort study based on observational data from 838 and 602 episodes of S. aureus and E. coli bloodstream infection, respectively. Swiss tertiary referral center. Adult patients with S. aureus and E. coli bloodstream infection, respectively, categorized according to low-dose acetylsalicylic acid therapy as outpatient or inpatient before bacteremia. None. Thirty-day all-cause mortality was analyzed in a total of 314 propensity score-matched S. aureus bloodstream infection and in 268 E. coli bloodstream infection patients, respectively (1:1 match of low-dose acetylsalicylic acid users and nonusers). S. aureus bloodstream infection cases and controls were equally matched for relevant confounders except treatment with statins, which was strongly associated with a low-dose acetylsalicylic acid use (p < 0.001). At day 30, 12.1% of cases and 27.4% of controls had died (hazard ratio, 0.40; p < 0.001). Low-dose acetylsalicylic acid use was associated with a reduced 30-day all-cause mortality in multivariate analysis (hazard ratio, 0.38; 95% CI, 0.21-0.69; p = 0.001) of matched patients and also of the entire cohort (n = 689) after adjustment for the propensity score (hazard ratio, 0.58, 95% CI, 0.34-0.98; p = 0.04). In contrast, low-dose acetylsalicylic acid use was not associated with the primary endpoint in patients with E. coli bloodstream infection (hazard ratio, 0.78; 95% CI, 0.40-1.55; p = 0.8). Low-dose acetylsalicylic acid at the time of bloodstream infection was strongly associated with a reduced short-term mortality in patients with S. aureus bloodstream infection. Future studies are required to investigate if early low-dose acetylsalicylic acid is a suitable treatment in patients with S. aureus bloodstream infection.

Use of Tigecycline in Pediatric Patients With Infections Predominantly Due to Extensively Drug-Resistant Gram-Negative Bacteria.

Emergence of extensively drug-resistant (XDR) bacteria has forced clinicians to use off-label antimicrobial agents such as tigecycline. We present our experience on salvage use of tigecycline for the treatment of infections caused by XDR Gram-negative bacteria in critically ill children and review published cases. We conducted a retrospective chart review in pediatric departments of a tertiary level hospital from January 2009 to May 2014. Patients were identified using pharmacy database. For the literature review, relevant articles were identified from PubMed. In our case series, 13 children (7 males) with a median age of 8 years (range, 2.5 months-14 years) received tigecycline for ≥2 days as treatment for healthcare-associated infections including 5 bacteremias, 6 lower respiratory tract infections, and 3 other infections. Isolated pathogens were XDR Gram-negative bacteria except 1. A loading dose (range, 1.8-6.5 mg/kg) was given in all except 2 cases. Maintenance dose was given at 1-3.2 mg/kg q12 h. Other antimicrobials including colistin and aminoglycosides (85% and 62%, respectively) were coadministered to all patients. No serious adverse events were detected in these very ill children. Twenty cases of children treated with tigecycline were previously published, mostly for multidrug-resistant/XDR bacteria. An episode of acute pancreatitis and neutrophil engraftment delay in 2 cases were reported during tigecycline treatment. Analyzing reported and all our cases together, mortality in bloodstream infections was 86%, whereas in nonbacteremic cases it was 24% (P = .009). Tigecycline, given at the range of administered doses as salvage therapy and in combination with other antimicrobial agents, seemed to be well tolerated in a series of mainly critically ill pediatric patients and demonstrated relatively good clinical response in nonbacteremic patients.

Antifungal Activity of Cinnamon Oil and Olive Oil against Candida Spp. Isolated from Blood Stream Infections.

Recently non-albicans Candida has emerged as a major cause of morbidity and mortality in blood stream infections. Some species of the Candida are becoming increasingly resistant to first line and second line antifungals such as echinocandins and fluconazole. In view of increasing global antifungal resistance, role of alternative and better antifungals like natural plant products need to be explored. Essential oils are known to exhibit antimicrobial activity against various fungi. Hence, we evaluated the efficacy of cinnamon oil and olive oil against Candida spp. To evaluate the invitro antifungal activity of olive oil and cinnamon oil against blood stream Candida isolates. The present prospective observational study was conducted in the Department of Microbiology at a tertiary care teaching hospital during one year June 2011-July 2012. Blood samples were collected from 1376 patients clinically suspected to have fungal septicaemia, out of which 100 (7.2%) Candida isolates obtained, were speciated by conventional methods. Antifungal susceptibility testing of all the isolates was done against fluconazole, voriconazole as per NCCL (M27-A2) and against olive oil and cinnamon oil by agar well diffusion method. Prevalence of Candidemia was 7.26%. C. albicans (85.3%) and C. parapsilosis (85.7%) were most sensitive to fluconazole followed by C. tropicalis (67.4%). All isolates were 100% sensitive to voriconazole. Both oils were found to be effective against nearly 50% of the Candida isolates. About 55.5% of fluconazole resistant C. krusei strains were sensitive to olive and cinnamon oil. Fluconazole resistant non-albicans Candida has emerged as major cause of Candidemia. Cinnamon and olive oil show marked sensitivity against albicans and non-albicans spp.

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

Risk factors for bloodstream infections due to colistin-resistant KPC-producing Klebsiella pneumoniae: results from a multicenter case–control–control study

The increasing prevalence of colistin resistance (ColR) Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (Kp) is a matter of concern because of its unfavourable impact on mortality of KPC-Kp bloodstream infections (BSI) and the shortage of alternative therapeutic options. A matched case–control–control analysis was conducted. The primary study end point was to assess risk factors for ColR KPC-Kp BSI. The secondary end point was to describe mortality and clinical characteristics of these infections. To assess risk factors for ColR, 142 patients with ColR KPC-Kp BSI were compared to two controls groups: 284 controls without infections caused by KPC-Kp (control group A) and 284 controls with colistin-susceptible (ColS) KPC-Kp BSI (control group B). In the first multivariate analysis (cases vs. group A), previous colistin therapy, previous KPC-Kp colonization, ≥3 previous hospitalizations, Charlson score ≥3 and neutropenia were found to be associated with the development of ColR KPC-Kp BSI. In the second multivariate analysis (cases vs. group B), only previous colistin therapy, previous KPC-Kp colonization and Charlson score ≥3 were associated with ColR. Overall, ColR among KPC-Kp blood isolates increased more than threefold during the 4.5-year study period, and 30-day mortality of ColR KPC-Kp BSI was as high as 51%. Strict rules for the use of colistin are mandatory to staunch the dissemination of ColR in KPC-Kp-endemic hospitals.

Microbiologic characteristics and predictors of mortality in bloodstream infections in intensive care unit patients: A 1-year, large, prospective surveillance study in 5 Italian hospitals

Bloodstream infections (BSIs) from multidrug-resistant (MDR) bacteria cause morbidity and mortality in intensive care unit (ICU) patients worldwide. This study investigated the incidence of BSIs in 5 adult general ICUs in Rome, Italy, and evaluated the mortality rate and risk factors associated with these infections. Over a 12-month period, 1,318 patients were enrolled. Demographic characteristics, Simplified Acute Physiology Score II (SAPS II), comorbidities, and BSI isolate data were collected. After stratification for the outcome, statistical analysis was performed to assess the impact of patient risk factors on in-hospital mortality. There were 324 BSIs in 175 patients recorded, with an in-hospital mortality rate of 46%. Univariate analysis revealed that SAPS II, cardiac comorbidity, and Klebsiella pneumoniae BSI were significantly associated with a higher risk of death. Having a K pneumoniae BSI and cardiac illness at admission were both confirmed to be associated with death by multivariate analysis (P=.0162 and P=.0158, respectively). Most of the K pneumoniae isolates showed high resistance rates to carbapenems. BSIs caused by K pneumoniae and cardiovascular comorbidity in ICU patients are associated with a higher risk of death. Thorough surveillance for MDR pathogens and stratification of the patients' risk on admission into the ICU are key to improving the outcomes of these infections.

Neonatal nosocomial bloodstream infections at a referral hospital in a middle-income country: burden, pathogens, antimicrobial resistance and mortality

Background:Data on nosocomial bloodstream infection (BSI) rates, pathogens, mortality and antimicrobial resistance in African neonates are limited.Methods:Nosocomial neonatal BSI at Tygerberg Hospital, Cape Town were retrospectively reviewed between 1 January 2009 and 31 December 2013. Laboratory and hospital data were used to determine BSI rates, pathogen profile, mortality and antimicrobial resistance in selected nosocomial pathogens.Results:Of 6521 blood cultures taken over 5 years, 1145 (17.6%) were culture-positive, and 717 (62.6%) discrete nosocomial BSI episodes were identified. Nosocomial BSI rates remained unchanged over time (overall 3.9/1000 patient days, 95% CI 3.6–4.2, χ2 for trend P = 0.23). Contamination rates were relatively high (5.1%, 95% CI 4.6–5.7%). Among BSI pathogens, Gram-negatives predominated (65% vs 31% Gram-positives and 4% fungal); Klebsiella pneumoniae (235, 30%), Staphylococcus aureus (112, 14%) and Enterococci (88, 11%) were most prevalent. Overall crude BSI mortality was 16% (112/717); Gram-negative BSI was significantly associated with mortality (P = 0.007). Mortality occurred mostly in neonates of very low (33/112, 29%) or extremely low (53/112, 47%) birthweight. Deaths attributed to nosocomial BSI declined significantly over time (χ2 for trend P = 0.01). The prevalence of antibiotic-resistant pathogens was high: methicillin-resistant Staphylococcus aureus 66%, multidrug-resistant A. baumanni 90% and extended-spectrum β-lactamase-producing K. pneumoniae 73%.Conclusion:The burden of nosocomial neonatal BSI at this middle-income country referral neonatal unit is substantial and remained unchanged over the study period, although attributable mortality declined significantly. Nosocomial BSI pathogens exhibited high levels of antimicrobial resistance.

Trends in paediatric bloodstream infections at a South African referral hospital.

BackgroundThe epidemiology of paediatric bloodstream infection (BSI) in Sub-Saharan Africa is poorly documented with limited data on hospital-acquired sepsis, impact of HIV infection, BSI trends and antimicrobial resistance.MethodsWe retrospectively reviewed paediatric BSI (0–14 years) at Tygerberg Children’s Hospital between 1 January 2008 and 31 December 2013 (excluding neonatal wards). Laboratory and hospital data were used to determine BSI rates, blood culture contamination, pathogen profile, patient demographics, antimicrobial resistance and factors associated with mortality. Fluconazole resistant Candida species, methicillin-resistant Staphylococcus aureus (MRSA), multi-drug resistant Acinetobacter baumannii and extended-spectrum beta-lactamase (ESBL) producing Enterobacteriaceae were classified as antimicrobial resistant pathogens.ResultsOf 17001 blood cultures over 6 years, 935 cultures isolated 979 pathogens (5.5% yield; 95% CI 5.3-5.7%). Contamination rates were high (6.6%, 95% CI 6.4-6.8%), increasing over time (p = 0.003). Discrete BSI episodes were identified (n = 864) with median patient age of 7.5 months, male predominance (57%) and 13% HIV prevalence. BSI rates declined significantly over time (4.6–3.1, overall rate 3.5 per 1000 patient days; 95% CI 3.3–3.7; Chi square for trend p = 0.02). Gram negative pathogens predominated (60% vs 33% Gram positives and 7% fungal); Klebsiella pneumoniae (154; 17%), Staphylococcus aureus (131; 14%) and Escherichia coli (97; 11%) were most prevalent. Crude BSI mortality was 20% (176/864); HIV infection, fungal, Gram negative and hospital-acquired sepsis were significantly associated with mortality on multivariate analysis. Hospital-acquired BSI was common (404/864; 47%). Overall antimicrobial resistance rates were high (70% in hospital vs 25% in community-acquired infections; p < 0.0001); hospital-acquired infection, infancy, HIV-infection and Gram negative sepsis were associated with resistance. S. pneumoniae BSI declined significantly over time (58/465 [12.5%] to 33/399 [8.3%]; p =0.04).ConclusionAlthough BSI rates declined over time, children with BSI had high mortality and pathogens exhibited substantial antimicrobial resistance in both community and hospital-acquired infections. Blood culture sampling technique and local options for empiric antimicrobial therapy require re-evaluation.

Prior statin use and 90-day mortality in Gram-negative and Gram-positive bloodstream infection: a prospective observational study.

In several studies on patients with bloodstream infection (BSI), prior use of statins has been associated with improved survival. Gram-positive and Gram-negative bacteria alert the innate immune system in different ways. We, therefore, studied whether the relation between prior statin use and 90-day total mortality differed between Gram-positive and Gram-negative BSI. We conducted a prospective observational cohort study of 1,408 adults with BSI admitted to Levanger Hospital between January 1, 2002, and December 31, 2011. Data on the use of statins and other medications at admission, comorbidities, functional status, treatment, and outcome were obtained from the patients’ hospital records. The relation of statin use with 90-day mortality differed between Gram-negative and Gram-positive BSI (p-value for interaction 0.01). Among patients with Gram-negative BSI, statin users had significantly lower 90-day total mortality [odds ratio (OR) 0.42, 95 % confidence interval (CI) 0.23–0.75, p = 0.003]. The association remained essentially unchanged after adjusting for the effect of sex, age, functional status before the infection, and underlying diseases that were considered confounders (adjusted OR 0.38, 95 % CI 0.20–0.72, p = 0.003). A similar analysis of patients with Gram-positive BSI showed no association of statin use with mortality (adjusted OR 1.22, 95 % CI 0.69–2.17, p = 0.49). The present study suggests that prior statin use is associated with a lower 90-day total mortality in Gram-negative BSI, but not in Gram-positive BSI.

Stratification of the impact of inappropriate empirical antimicrobial therapy for Gram-negative bloodstream infections by predicted prognosis.

The bloodstream infection mortality risk score (BSIMRS) predicts the outcome of patients with Gram-negative bloodstream infections (BSI) with high discrimination. This retrospective cohort study examined the impact of inappropriate antimicrobial therapy on mortality in adult patients with Gram-negative BSI admitted to Palmetto Health Hospitals in Columbia, SC, USA, from 1 January 2011 to 31 December 2012 after stratification by predicted prognosis at initial presentation using BSIMRS. A multivariate Cox regression model was used to identify independent risk factors for 28-day mortality overall and within each predefined BSIMRS category (<5, 5 to 9, and ≥ 10). Relative risk reduction (RRR), absolute risk reduction (ARR), and number needed to treat (NNT) were calculated from a predictive logistic regression model of mortality. Overall, 390 unique patients with first episodes of Gram-negative BSI were identified. The median age was 66 years, and 229 (59%) were women. There was significant association between inappropriate antimicrobial therapy and mortality in patients with BSIMRS of 5 to 9 (adjusted hazard ratio [aHR], 3.55; 95% confidence intervals [CI], 1.22 to 8.31; P = 0.02) and BSIMRS of ≥ 10 (aHR, 4.99; 95% CI, 1.09 to 22.87; P = 0.04) but not in those with BSIMRS of <5 (aHR, 3.34; 95% CI, 0.17 to 22.77; P = 0.34). RRR, ARR, and NNT were 0.25, 0.02, and 63 for BSIMRS of <5; 0.56, 0.32, and 3 for BSIMRS of 5 to 9; and 0.39, 0.39, and 3 for BSIMRS of ≥ 10, respectively. There is a significant benefit from appropriate antimicrobial therapy in patients with Gram-negative BSI with guarded (BSIMRS of 5 to 9) and poor (BSIMRS of ≥ 10) predicted prognosis. Survival difference remains unclear among those with good predicted prognosis (BSIMRS of <5) at initial presentation.

An outbreak of extremely drug-resistant Pseudomonas aeruginosa in a tertiary care pediatric hospital in Italy.

BackgroundExtensively drug-resistant Pseudomonas aeruginosa (XDR-PA) isolates are susceptible to only one or two classes of antibiotics. In 2011–2012, we investigated an outbreak of XDR-PA affecting children with onco-hematological diseases.MethodsOutbreak investigation included ascertainment of cases, tracing of intestinal carriers and environmental surveillance. Contact precautions were adopted for patients with infection or colonization. Isolates were tested for antimicrobial susceptibility; phenotypic confirmation of carbapenemase production was performed, and carbapenemase genes were tested by multiplex polymerase-chain-reaction (PCR). Genotypes were determined by pulsed-field gel electrophoresis (PFGE).ResultsXDR-PA was isolated from 27 patients; 12 had bacteremia, 6 other infections and 9 were colonized. Severe neutropenia was significantly associated with bacteremia. Bloodstream-infection mortality rate was 67%. All isolates were resistant to carbapenems, cephalosporins and penicillins + β-lactamase inhibitors. Isolates were susceptible only to colistin in 22 patients, to colistin and amikacin in 4, and to ciprofloxacin and colistin in 1. PFGE results identified 6 subtypes of a single genotype, associated with clusters of cases, and 4 sporadic genotypes. Two sporadic isolates were metallo-β-lactamase producers, negative to PCR. All other isolates were metallo-β-lactamase producers due to the presence of a VIM carbapenemase. Incidence of XDR-PA infections decreased from 0.72 cases/1,000 inpatient-days in March 2011-March 2012, to 0.34/1,000 in April-December 2012, after implementation of active finding of intestinal carriers on all onco-hematological inpatients.ConclusionsControl measures targeting intestinal carriers are crucial in limiting in-hospital transmission of XDR-PA polyclonal strains, protecting more vulnerable patients, such as severely neutropenic children, from developing clinical infections.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2334-14-494) contains supplementary material, which is available to authorized users.