Nosocomial infection and antibiotic use: a second national prevalence study in Germany.

BACKGROUND: In 2011, seventeen years after the first national study on the prevalence of nosocomial infections and antibiotic use in German hospitals, a second national prevalence study was carried out according to the specifications of the European Centre for Disease Prevention and Control (ECDC). METHODS: The ECDC protocol, containing uniform surveillance definitions and ascertainment methods, was implemented. The only infections counted were those that were active or under treatment with antibiotics on the day of the study. In addition to the representative sample required by the ECDC, which consisted of 46 hospitals, further hospitals participated on a voluntary basis. RESULTS: Data on 41 539 patients in 132 hospitals were analyzed. The prevalence of infections that had arisen during the current hospital stay was 3.8% in the overall group and 3.4% in the representative sample of 9626 patients in 46 hospitals. The prevalence of all nosocomial infections, including those acquired before the current hospital stay and still present upon admission, was 5.1% in both the overall group and the representative sample. The prevalence of antibiotic use on the day of the study was 25.5% and 23.3% in the two groups, respectively. CONCLUSION: The prevalence of nosocomial infection has not changed since 1994, but the prevalence of antibiotic use has increased. In interpreting these findings, one should bear in mind that confounders may have influenced them in different directions: The mean length of hospital stay is now shorter than in 1994, but the mean age of hospitalized patients is higher.

Antibiotic usage in German hospitals: results of the second national prevalence study.

OBJECTIVES: Data on antibiotic usage (AU) are helpful for improvement of antibiotic stewardship. This study describes findings and targets for quality improvement in German hospitals identified in a national point prevalence survey of healthcare-associated infections and AU. METHODS: The survey was organized by the German National Reference Centre for Surveillance of Nosocomial Infections (NRZ) as part of a pan-European survey organized by the European Centre for Disease Prevention and Control (ECDC). Infection control personnel of participating hospitals were trained in methodology and performed the survey in September and October 2011. Data on the antimicrobials prescribed (e.g. compounds and indications) were analysed by the NRZ. In order to submit national data to the ECDC, a representative sample of 46 hospitals was generated, although other hospitals were invited to participate in the survey if interested. RESULTS: In total, 41,539 patients were surveyed in 132 hospitals. AU prevalence in these hospitals and in the representative sample did not differ significantly [25.5% (95% CI 24.5%-26.6%) and 23.3% (95% CI 21.3%-25.5%), respectively]. AU rates were higher compared with a previous survey in 1994. Antimicrobials were administered for treatment in 70% and prophylaxis in 30% of cases. Surgical prophylaxis (SP) was prolonged (>1 day) in 70% of cases. Indication was documented in patients' charts in 73% of administrations. The most frequently used agents were cefuroxime (14.3%), ciprofloxacin (9.8%) and ceftriaxone (7.5%). CONCLUSIONS: The study identified several points for improvement, e.g. the large amount of prolonged SP, the extensive use of broad-spectrum antibiotics and the high percentage of antibiotic administration without documented indication.

Attributable costs of ventilator-associated lower respiratory tract infection (LRTI) acquired on intensive care units: a retrospectively matched cohort study.

BACKGROUND: Lower respiratory tract infections (LRTI) are the most common hospital-acquired infections on ICUs. They have not only an impact on each patient's individual health but also result in a considerable financial burden for the healthcare system. Our aim was to determine the costs and the length of stay of patients with ICU-acquired LRTI. METHODS: We used a retrospectively matched cohort design, comparing patients with ICU-acquired LRTI and ICU patients without LRTI. LRTI was diagnosed using the definitions of the Centers for Disease Control and Prevention (CDC). Study period was from January to December 2010 analyzing patients from 10 different ICUs (medical, surgical, interdisciplinary). The device utilization ratio was defined as number of ventilator days divided by number of patient days and the device-associated LRTI rate was defined as number of ventilator associated LRTI divided by number of ventilator days. Patients were matched by age, sex, and prospectively obtained Simplified Acute Physiology Score II (SAPS II). The length of ICU stay of control patients needed to be at least as long as that of LRTI-patients before onset of LRTI. We used the Wilcoxon signed-rank test for continuous variables and the McNemar's test for categorical variables. RESULTS: The analyzed ICUs had 40,772 patient days in the study period with a median ventilation utilization ratio of 56 (IQR 42-65). The median device-associated LRTI rate was 3.35 (IQR 0.96-5.36) per 1,000 ventilation days. We analyzed 49 patients with ICU-acquired LRTI and 49 respective controls without LRTI. The median hospital costs for LRTI patients were significantly higher than for patients without LRTI (45,041 € vs. 26,467 €; p < .001). The attributable costs per LRTI patient were 17,015 € (p < .001). Patients with ICU acquired LRTI stayed longer in the hospital than patients without (36 days vs. 24 days; p = 0.011). An LRTI lead to an attributable increase in length of stay by 9 days (p = 0.011). CONCLUSIONS: ICU-acquired LRTI is associated with increased hospital costs and prolonged hospital stay. Hospital management should therefore implement control measurements to keep the incidence of ICU-acquired LRTI as low as possible.

Concordance between European and US case definitions of healthcare-associated infections.

BACKGROUND: Surveillance of healthcare-associated infections (HAI) is a valuable measure to decrease infection rates. Across Europe, inter-country comparisons of HAI rates seem limited because some countries use US definitions from the US Centers for Disease Control and Prevention (CDC/NHSN) while other countries use European definitions from the Hospitals in Europe Link for Infection Control through Surveillance (HELICS/IPSE) project. In this study, we analyzed the concordance between US and European definitions of HAI. METHODS: An international working group of experts from seven European countries was set up to identify differences between US and European definitions and then conduct surveillance using both sets of definitions during a three-month period (March 1st -May 31st, 2010). Concordance between case definitions was estimated with Cohen's kappa statistic (κ). RESULTS: Differences in HAI definitions were found for bloodstream infection (BSI), pneumonia (PN), urinary tract infection (UTI) and the two key terms "intensive care unit (ICU)-acquired infection" and "mechanical ventilation". Concordance was analyzed for these definitions and key terms with the exception of UTI. Surveillance was performed in 47 ICUs and 6,506 patients were assessed. One hundred and eighty PN and 123 BSI cases were identified. When all PN cases were considered, concordance for PN was κ = 0.99 [CI 95%: 0.98-1.00]. When PN cases were divided into subgroups, concordance was κ = 0.90 (CI 95%: 0.86-0.94) for clinically defined PN and κ = 0.72 (CI 95%: 0.63-0.82) for microbiologically defined PN. Concordance for BSI was κ = 0.73 [CI 95%: 0.66-0.80]. However, BSI cases secondary to another infection site (42% of all BSI cases) are excluded when using US definitions and concordance for BSI was κ = 1.00 when only primary BSI cases, i.e. Europe-defined BSI with "catheter" or "unknown" origin and US-defined laboratory-confirmed BSI (LCBI), were considered. CONCLUSIONS: Our study showed an excellent concordance between US and European definitions of PN and primary BSI. PN and primary BSI rates of countries using either US or European definitions can be compared if the points highlighted in this study are taken into account.

Viremia after lung transplant: a cohort study on risk factors and symptoms associated with detection of Epstein-Barr virus.

Background-The frequency and impact of detection of Epstein-Barr virus in the blood of lung and heart-lung transplant recipients in the postoperative period is poorly characterized.Objective-To investigate the frequency of virus detection, associated clinical symptoms and risk factors, and influence of virus detection on outcome.Methods-A cohort of 98 lung transplant recipients were monitored for Epstein-Barr virus in blood before transplant and during their posttransplant hospital stay (median 4 weeks, range 1-21 weeks). Patients were followed up for retransplant or death for a median of 17 months.Results-Epstein-Barr virus DNA was detected in 15 recipients (18.1%) before and in 39 recipients (41.5%) after transplant. Median viral load after transplant was 2300 copies per milliliter of blood (range, 900-45 000 copies/mL). Detection of Epstein-Barr virus DNA before transplant and mechanical ventilation before transplant were associated with detection of Epstein-Barr virus DNA after transplant. Shortness of breath, fatigue, and hoarseness were associated with detection of viral DNA after transplant. The incidence of retransplant or death was not increased in recipients who had viral DNA detected in their blood.Conclusions-Epstein-Barr virus DNA in the blood before transplant and mechanical ventilation before transplant were associated with detection of viral DNA after transplant. Detection of viral DNA after transplant was frequent and clinically relevant.

Laminar airflow ceiling size: no impact on infection rates following hip and knee prosthesis.

OBJECTIVE: Laminar airflow (LAF) systems are widely used, at least in orthopedic surgery. However, there is still controversial discussion about the influence of LAF on surgical site infection (SSI) rates. The size of the LAF ceiling is also often a question of debate. Our objective is to determine the effect of this technique under conditions of actual rather than ideal use. DESIGN: Cohort study using multivariate analysis with generalized estimating equations method. SETTING: Data for hip and knee prosthesis procedures from hospitals participating in the German national nosocomial infection surveillance system (KISS) from July 2004 to June 2009 were used for analysis. PATIENTS: A total of 33,463 elective hip prosthesis procedures due to arthrosis (HIP-A) from 48 hospitals, 7,749 urgent hip prosthesis procedures due to fracture (HIP-F) from 41 hospitals, and 20,554 knee prosthesis (KPRO) procedures from 38 hospitals were included. METHODS: The data were analyzed for hospitals with and without LAF in the operating rooms and by the size of the LAF ceiling. The endpoints were severe SSI rates. RESULTS: The overall severe SSI rate was 0.74 per 100 procedures for HIP-A, 2.39 for HIP-F, and 0.63 for KPRO. For all 3 prosthesis types, neither LAF nor the size of the LAF ceiling was associated with lower infection risk. CONCLUSIONS: The data demonstrate consistency and reproducibility with the results from earlier registry studies. Neither LAF nor ceiling size had an impact on severe SSI rates.

Impact of department volume on surgical site infections following arthroscopy, knee replacement or hip replacement.

OBJECTIVE: To examine the association between surgical department volume and the risk of surgical site infections (SSI) after orthopaedic procedures. BACKGROUND: A minimum volume regulation of at least 50 knee replacements per year was implemented in 2006 in German surgical departments. METHODS: SSI rates were obtained from Krankenhaus-Infektions-Surveillance-System, the German national nosocomial infections surveillance system (January 2003-June 2008). The authors analysed the data by linear regression models. The adjusted ORs were estimated based on general estimating equation models to assess the independent effect of department volume (low, ie, ≤ 50, medium, ie, >50 and ≤ 100, and high, ie, >100 procedures annually). RESULTS: A total of 206 surgical departments performed 14,339 arthroscopies, 63,045 knee replacements and 43,180 hip replacements during the 5.5-year study period. SSI rates were significantly higher in departments with a procedure volume of ≤ 50 arthroscopies and knee replacements. A higher threshold of 100 procedures per year did lead to a significant decrease in SSI rates for all three procedures in the univariate analysis. The multivariate analysis showed that the risk of SSI in low volume departments was sevenfold higher for arthroscopies and twofold higher for knee replacement than in medium volume departments. SSI risk after hip replacement was significantly lower in high volume centres. CONCLUSION: The authors' findings offer some support for recommendations to concentrate arthroscopy and knee replacement in surgical departments with more than 50 procedures and hip replacement in departments with more than 100 procedures per year in order to reduce SSI.

The microbiological quality of air improves when using air conditioning systems in cars.

BACKGROUND: Because of better comfort, air conditioning systems are a common feature in automobiles these days. However, its impact on the number of particles and microorganisms inside the vehicle--and by this its impact on the risk of an allergic reaction--is yet unknown. METHODS: Over a time period of 30 months, the quality of air was investigated in three different types of cars (VW Passat, VW Polo FSI, Seat Alhambra) that were all equipped with a automatic air conditioning system. Operation modes using fresh air from outside the car as well as circulating air from inside the car were examined. The total number of microorganisms and the number of mold spores were measured by impaction in a high flow air sampler. Particles of 0.5 to 5.0 microm diameter were counted by a laser particle counter device. RESULTS: Overall 32 occasions of sampling were performed. The concentration of microorganisms outside the cars was always higher than it was inside the cars. Few minutes after starting the air conditioning system the total number of microorganisms was reduced by 81.7%, the number of mold spores was reduced by 83.3%, and the number of particles was reduced by 87.8%. There were no significant differences neither between the types of cars nor between the types of operation mode of the air conditioning system (fresh air vs. circulating air). All parameters that were looked for in this study improved during utilization of the car's air conditioning system. CONCLUSIONS: We believe that the risk of an allergic reaction will be reduced during use also. Nevertheless, we recommend regular maintenance of the system and replacement of older filters after defined changing intervals.

Outbreak of carbapenem-resistant Acinetobacter baumannii carrying the carbapenemase OXA-23 in a German university medical centre.

A prolonged outbreak of carbapenem-resistant Acinetobacter baumannii in a German university medical centre in 2006 was investigated; the investigation included a descriptive epidemiological analysis, a case-control study, environmental sampling, molecular typing of A. baumannii isolates using PFGE and repetitive-sequence-based PCR (rep-PCR) typing, and detection of OXA-type carbapenemases by multiplex PCR. Thirty-two patients acquired the outbreak strain in five intensive care units (ICUs) and two regular wards at a tertiary care hospital within 10 months. The outbreak strain was resistant to penicillins, cephalosporins, ciprofloxacin, gentamicin, tobramycin, imipenem and meropenem, and carried the bla(OXA-23)-like gene. Based on PFGE and rep-PCR typing, it was shown to be related to the pan-European A. baumannii clone II. The most likely mode of transmission was cross-transmission from colonized or infected patients via the hands of health-care workers, with the severity of disease and intensity of care (therapeutic intervention scoring system 28 score >median) being independently associated with acquisition of the outbreak strain (odds ratio 6.67, 95 % confidence interval 1.55-36.56). Control of the outbreak was achieved by enforcement of standard precautions, education of personnel, screening of ICU patients for carbapenem-resistant A. baumannii and cohorting of patients. This is believed to be the first report of an outbreak of A. baumannii carrying the carbapenemase OXA-23 in Germany.

Decrease of deep sternal surgical site infection rates after cardiac surgery by a comprehensive infection control program.

When we noticed an increasing incidence of deep sternal surgical site infections (DSSI), a bundle of interdisciplinary infection control measures was initiated in order to prevent further cases of DSSI. Adherence to infection control measures was re-inforced, which included (1) methicillin-resistant Staphylococcus aureus (MRSA) screening, (2) bacterial decolonisation measures, (3) hair clipping instead of shaving, (4) education, (5) good stewardship for antibiotic prophylaxis, (6) change of surgical gloves after sternotomy and after sternal wiring, (7) new bandage techniques, (8) leaving the wound primarily covered for at least 48 h. We checked for potential risk factors in a case-control study (120 patients each) by multivariate analysis. A significant decrease of DSSI from 3.61% (CI 95: 2.98-4.35) down to 1.83% (CI 95: 1.08-2.90) occurred. Independent significant risk factors for DSSI were age >68 years (OR=2.47; CI 95: 1.33-4.60), diabetes mellitus (OR=4.84; CI 95: 2.25-10.4), and intra-operative blood glucose level >8 mmol/l (OR=2.27; CI 95: 1.17-4.42). Protective factors were preoperative antibiotic prophylaxis (OR=0.31; CI 95: 0.13-0.70) and extubation on the day of surgery (OR=0.25; CI 95: 0.11-0.55). Close co-operation between clinical physicians and the infection control team significantly reduced the rate of DSSI. Thus, cardiac surgeons should know the local baseline DSSI rate, e.g. by surveillance, and should be aware of the risk factors for DSSI cases.

Early- and late-onset pneumonia: is this still a useful classification?

The choice of empirical treatment of nosocomial pneumonia in the intensive-care unit (ICU) used to rely on the interval after the start of mechanical ventilation. Nowadays, however, the question of whether in fact there is a difference in the distribution of causative pathogens is under debate. Data from 308 ICUs from the German National Nosocomial Infection Surveillance System, including information on relevant pathogens isolated in 11,285 cases of nosocomial pneumonia from 1997 to 2004, were used for our evaluation. Each individual pneumonia case was allocated either to early- or to late-onset pneumonia, with three differentiation criteria: onset on the 4th day, the 5th day, or the 7th day in the ICU. The frequency of pathogens was evaluated according to these categories. A total of 5,066 additional cases of pneumonia were reported from 2005 to 2006, after the CDC criteria had been modified. From 1997 to 2004, the most frequent microorganisms were Staphylococcus aureus (2,718 cases, including 720 with methicillin [meticillin]-resistant S. aureus), followed by Pseudomonas aeruginosa (1,837 cases), Klebsiella pneumoniae (1,305 cases), Escherichia coli (1,137 cases), Enterobacter spp. (937 cases), streptococci (671 cases), Haemophilus influenzae (509 cases), Acinetobacter spp. (493 cases), and Stenotrophomonas maltophilia (308 cases). The order of the four most frequent pathogens (accounting for 53.7% of all pathogens) was the same in both groups and was independent of the cutoff categories applied: S. aureus was first, followed by P. aeruginosa, K. pneumoniae, and E. coli. Thus, the predictabilities of the occurrence of pathogens were similar for the earlier (1997-to-2004) and later (2005-to-2006) time frames. This classification is no longer helpful for empirical antibiotic therapy, since the pathogens are the same for both groups.

Surveillance with successful reduction of central line-associated bloodstream infections among neutropenic patients with hematologic or oncologic malignancies.

To determine nosocomial catheter-associated bloodstream infections (CA-BSIs) and to improve the prevention measures, we performed a prospective surveillance in our hematopoietic stem cell transplantation unit at our university hospital. During the 36-month study period all patients with at least two consecutive neutropenic days (NDs) were included. After the first 18 months the recorded data were analyzed and compared with reference data and were then presented to the clinical staff. An intensive training to improve the handling of central venous lines was performed afterwards. At the end of the last 18-month study period the data were evaluated and a multivariate analysis was conducted. Altogether 268 patients were treated for a period of 10,013 patient days including 4,286 NDs. A total of 202/268 (75.4%) patients underwent transplantation (157/76.6% allogeneic, 48/23.4% autologous). Eighty-seven CA-BSIs were identified. The incidence density was 24.3 CA-BSI episodes per 1,000 NDs in the first period and 16.2 in the second. A significant reduction in the CA-BSI rate of adults was achieved (OR 0.58; 95% CI 0.339-0.987; p < 0.05). Significant risk factors for nosocomial CA-BSIs during the neutropenic phase were AML as underlying disease as well as transplantations.

Ten years of KISS: the most important requirements for success.

Ten years ago, in January 1997, data collection for the German national nosocomial infection surveillance system was established, which is known by the acronym KISS (Krankenhaus-Infektions-Surveillance-System). Meanwhile KISS was able to demonstrate a beneficial effect from ongoing surveillance activities and appropriate feedback to the users in combination with reference data for ventilator associated pneumonia, primary bloodstream infections and surgical site infections. Significant reductions of infection rates between 20-30% over 3 years periods in the components for intensive care units, operative departments and neonatal intensive care units were demonstrated. Due to our experience the following requirements have to be fulfilled to keep a surveillance system successful over longer periods: close contact between the participating institutions, consideration of new developments, timely regular data feedback and constant reevaluation of the way of data presentation, data validity and demonstration of its contribution to the reduction of healthcare associated infections (HAI). The article describes in more detail how KISS tries to fulfill these requirements.

Mortality attributable to hospital-acquired infections among surgical patients.

We performed a multicenter prospective matched cohort study to evaluate the mortality attributable to hospital-acquired infections among 12,791 patients admitted to surgical departments. We were able to match 731 patients with 1 or more hospital-acquired infections (ie, case patients) with 731 patients without a hospital-acquired infection (ie, control patients) at a 1:1 ratio. Of the 731 case patients, 42 (5.7%) died; of the 731 control patients, 23 (3.1%) died--a significant difference of 2.6%.

Impact of a silver layer on the membrane of tap water filters on the microbiological quality of filtered water.

BACKGROUND: Bacteria in the hospital's drinking water system represent a risk for the acquisition of a nosocomial infection in the severely immunocompromised host. Terminal tap water filters may be used to prevent nosocomial Legionnaires' disease. We present data from water samples using an improved kind of tap water filters. METHODS: In a blinded study on an intermediate care unit of the thoracic surgery department, a modified type of the Germlyser water filter (Aqua-Free Membrane Technology) with a newly-introduced silver layer on the filtration membrane was compared to its preceding type without such a layer on 15 water outlets. We determined growth of Legionella, other pathogenic bacteria, and the total heterotrophic plate count in unfiltered water and filtered water samples after filter usage intervals of 1 through 4 weeks. RESULTS: A total of 299 water samples were tested. Twenty-nine of the 60 unfiltered water samples contained Legionella of various serogroups (baseline value). In contrast, all samples filtered by the original water filter and all but one of the water samples filtered by the modified filter type remained Legionella-free. No other pathogenic bacteria were detected in any filtered sample. The total plate count in water samples increased during use of both kinds of filters over time. However, for the first 7 days of use, there were significantly fewer water samples containing >100 CFU per mL when using the new filter device compared with the older filters or taps with no filter. No advantage was seen thereafter. CONCLUSION: The use of this type of terminal water filter is an appropriate method to protect immunocompromised patients from water-borne pathogens such as Legionella.

Operating room ventilation with laminar airflow shows no protective effect on the surgical site infection rate in orthopedic and abdominal surgery.

OBJECTIVE: To evaluate whether operating room (OR) ventilation with (vertical) laminar airflow impacts on surgical site infection (SSI) rates. DESIGN: Retrospective cohort-study based on routine surveillance data. PATIENTS AND METHODS: Sixty-three surgical departments participating voluntarily in the German national nosocomial infections surveillance system "KISS" were included (a total of 99,230 operations). Active SSI surveillance was performed according to the methods and definitions given by the US National Nosocomial Infection Surveillance system. Surgical departments were stratified according to type of OR ventilation used: (1) turbulent ventilation with high-efficiency particulate air-filtered air, and (2) HEPA-filtered (vertical) laminar airflow ventilation. Multivariate analyses were performed by the generalized estimating equations method to control for the following variables as possible confounders: (a) Patient-based: wound contamination class, ASA score, operation duration, patients' age and gender, endoscopic operation; (b) Hospital-based: the number of beds in the hospital, its academic status, operation frequency, and long-term participation in KISS. RESULTS: The risk for severe SSI after hip prosthesis implantation was significantly higher using laminar airflow OR ventilation (1.63 < 1.06; 2.52>), as compared with turbulent ventilation. The adjusted odds ratios for the other operative procedures analyzed were: knee prosthesis 1.76 < 0.80, 3.85>; appendectomy 1.52 < 0.91, 2.53>; cholecystectomy 1.37 < 0.63, 2.97>; colon surgery 0.85 < 0.49, 1.49>; and herniorrhaphy 1.48 < 0.67; 3.25>. CONCLUSIONS: Unexpectedly, in this analysis, which controlled for many patient and hospital-based confounders, OR ventilation with laminar airflow showed no benefit and was even associated with a significantly higher risk for severe SSI after hip prosthesis.

Clinical relevance of and risk factors for HSV-related tracheobronchitis or pneumonia: results of an outbreak investigation.

INTRODUCTION: Herpes simplex virus (HSV) type 1 was identified in respiratory specimens from a cluster of eight patients on a surgical intensive care unit within 8 weeks. Six of these patients suffered from HSV-related tracheobronchitis and one from HSV-related pneumonia only. Our outbreak investigation aimed to determine the clinical relevance of and risk factors associated with HSV-related tracheobronchitis or pneumonia in critically ill patients, and to investigate whether the cluster was caused by nosocomial transmission. METHODS: A retrospective cohort study was performed to identify risk factors for the outcomes of HSV-related tracheobronchitis or pneumonia and death using univariable analysis as well as logistic regression analysis. Viruses were typed by molecular analysis of a fragment of the HSV type 1 glycoprotein G. RESULTS: The cohort of patients covering the outbreak period comprised 53 patients, including six patients with HSV-related tracheobronchitis and one patient with pneumonia only. HSV-related tracheobronchitis or pneumonia was associated with increased mortality (100% in patients with versus 17.8% in patients without HSV-related tracheobronchitis or pneumonia; P < 0.0001). The interaction of longer duration of ventilation and tracheotomy was associated with HSV-related tracheobronchitis or pneumonia in multivariable analysis. Identical HSV type 1 glycoprotein G sequences were found in three patients and in two patients. The group of three identical viral sequences belonged to a widely circulating strain. The two identical viral sequences were recovered from bronchoalveolar lavages of one patient with HSV-related tracheobronchitis and of one patient without clinical symptoms. These viral sequences showed unique polymorphisms, indicating probable nosocomial transmission. CONCLUSION: HSV-related tracheobronchitis or pneumonia is associated with increased mortality in critically ill patients. Care should be taken to avoid nosocomial transmission and early diagnosis should be attempted.

Clinical impact of infections caused by ESBL-producing E. coli and K. pneumoniae.

The outcome of infections occurring at different anatomic sites caused by ESBL-producing E. coli or K. pneumoniae was retrospectively analysed for a 3-y period. 23 cases were compared to 46 controls with infections caused by third-generation cephalosporin-susceptible strains matched by age, severity of illness and duration of hospitalization before onset of infection. Only 27.8% of cases received appropriate empirical antimicrobial therapy compared with 79.6% of controls (OR(paired)=0.053, p=0.001). This did not result in higher costs of antibiotic therapy, a longer median post-infection hospital stay or higher mortality in cases of patients with urinary tract or wound infections. In cases of patients with respiratory tract and bloodstream infections (RTI/BSI), median costs of definitive antibiotic treatment were significantly higher than in controls (325 vs 58.9 Euros, p=0.002). Moreover, more case patients with RTI/BSI had a post-infection stay exceeding the 75th percentile of 15 d on ICU and of 18 d in hospital, respectively (50% vs 6.67%, p=0.034). There was no difference in in-hospital mortality between case and control patients with RTI/BSI (25% vs 20%, p=1.0).

Outbreaks in neonatal intensive care units - they are not like others.

BACKGROUND: Outbreaks of health care-associated infections in neonatal intensive care units (NICUs) are frequent and have received more attention in medical literature than outbreaks from other types of intensive care units (ICUs). The objective of this systematic review was to identify differences between outbreaks of health care-associated infections in NICUs and other ICUs as reported to date in the medical literature. METHODS: Screening the outbreak database (http://www.outbreak-database.com), a systematic comparison of outbreaks was performed with the following categories: causing pathogen, type of infection, sources identified, and measures taken to stop the outbreak. RESULTS: Two hundred and seventy-six outbreaks were reported from NICUs and 453 from other ICU types. Enterobacteriaceae were significantly more often responsible for NICU outbreaks, whereas nonfermenting bacteria are more frequently identified in other ICU types. On average, 23.9 patients and 1.8 health care workers were involved in NICU outbreaks. Average mortality in NICU outbreak was 6.4% (1.5 newborns on average). In 48.6% of NICU outbreaks the authors were unable to identify the sources compared with 38.0% in other ICU outbreaks. The most important infection control measures were significantly more often implemented in NICUs than in other ICUs. CONCLUSIONS: Systematic outbreak analysis is essential for gaining insights into the control of NICU outbreaks.

Post-operative nosocomial infections after lung and heart transplantation.

BACKGROUND: Thoracic transplant recipients appear to be at high risk for post-operative infections. Therefore, we investigated the incidence and risk factors of post-operative nosocomial infections (NIs) in lung and heart transplant recipients. METHODS: From January 2002 to December 2003, a cohort of 208 consecutive thoracic transplant recipients (137 lung transplants [LTx], 51 heart transplants [HTx] and 20 combined transplants [CLTx]) were analyzed for post-operative infections and in-hospital mortality. NIs were determined according to CDC definitions. Uni- and multivariate risk factor analyses were performed. RESULTS: Of the 157 NIs, 59 were pneumonia (37.6%), 34 primary sepsis (21.6%), 34 urinary tract (21.6%) and 30 surgical site (19.1%). Despite a total NI incidence of 75.5%, more importantly 56.3% of all patients remained free from any infection. CLTx patients had a higher risk of developing NIs (odds ratio [OR] 4.97; 95% confidence interval [CI] 1.74 to 15.34). Risk factors for NIs were volume reduction procedures in LTx (OR 2.6; 95% CI 1.13 to 6.30) and re-do Tx (OR 5.25; 95% CI 1.41 to 26.8). In LTx patients, pre-operative colonization with gram-negative rods was found to be a risk factor for post-transplant pneumonia (OR 3.7; 95% CI 1.19 to 11.37). Presence of NI (OR 2.53; 95% CI 1.07 to 6.25) was a risk factor for mortality, as was cystic fibrosis (OR 3.20; 95% CI 1.27 to 7.92) and ventilation prior to transplantation (OR 4.00; 95% CI 1.28 to 12.09). CONCLUSION: The mortality risk associated with NIs requires close infection surveillance for developing specific preventive anti-infection strategies.