Stenotrophomonas maltophilia and antibiotic use in German intensive care units: data from Project SARI (Surveillance of Antimicrobial Use and Antimicrobial Resistance in German Intensive Care Units)

Risk factors for the selection of Stenotrophomonas maltophilia were analysed by correlating antimicrobial use and structure parameters (e.g. hospital type) with the incidence density of S. maltophilia and the percentage of S. maltophilia isolated from 39 intensive care units (ICUs). SARI (Surveillance of Antimicrobial Use and Antimicrobial Resistance in German Intensive Care Units) is a prospective unit- and laboratory-based surveillance system that collects data on the 13 most important organisms responsible for nosocomial infections. The percentage of S. maltophilia among these organisms and the number of S. maltophilia per 1000 patient-days were calculated. The data were subsequently correlated with antibiotic use density calculated in defined daily doses (DDDs) per 1000 patient-days and structure parameters. The data covered a total of 28 266 isolates and 431 351 DDDs. The antibiotic use density ranged from 427 to 2218, with the median being 1346. Over the two-year period, the median of S. maltophilia per 1000 patient-days was 1.4 (range 0-7.6). Calculation of antibiotic use and S. maltophilia per 1000 patient-days showed a significant positive correlation with the use of carbapenems, ceftazidime, glycopeptides and fluoroquinolones, as well as with total antibiotic use. In the multiple logistic regression analysis, carbapenem use and >12 ICU beds were independently and positively associated with a high number of S. maltophilia per 1000 patient-days. Benchmarking data provided for incidence densities of S. maltophilia in ICUs revealed the heterogeneous situation of the burden of S. maltophilia in individual ICUs. The multi-centre data showed that carbapenem use and >12 ICU beds were independent risk factors for the isolation of S. maltophilia.     

Development of a surveillance system for methicillin-resistant Staphylococcus aureus in German hospitals.

OBJECTIVE: To determine the appropriate method to calculate the rate of methicillin-resistant Staphylococcus aureus (MRSA) infection and colonization (hereafter, MRSA rates) for interhospital comparisons, such that the large number of patients who are already MRSA positive on admission is taken into account. DESIGN: A prospective, multicenter, hospital-based surveillance of MRSA-positive case patients from January through December 2004. SETTING: Data from 31 hospitals participating in the German national nosocomial infections surveillance system (KISS) were recorded during routine surveillance by the infection control team at each hospital. RESULTS: Data for 4,215 MRSA-positive case patients were evaluated. From this data, the following values were calculated. The median incidence density was 0.71 MRSA-positive case patients per 1,000 patient-days, and the median nosocomial incidence density was 0.27 patients with nosocomial MRSA infection or colonization per 1,000 patient-days (95% CI, 0.18-0.34). The median average daily MRSA burden was 1.13 MRSA patient-days per 100 patient-days (95% CI, 0.86-1.51), with the average daily MRSA burden defined as the total number of MRSA patient-days divided by the total number of patient-days times 100. The median MRSA-days-associated nosocomial MRSA infection and colonization rate, which describes the MRSA infection risk for other patients in hospitals housing large numbers of MRSA-positive patients and/or many patients who were MRSA positive on admission, was 23.1 cases of nosocomial MRSA infection and colonization per 1,000 MRSA patient-days (95% CI, 17.4-28.6). The values were also calculated for various MRSA screening levels. CONCLUSIONS: The MRSA-days-associated nosocomial MRSA rate allows investigators to assess the extent of MRSA colonization and infection at each hospital, taking into account cases that have been imported from other hospitals, as well as from the community. This information provides an appropriate incentive for hospitals to introduce further infection control measures.     

Impact of contact and droplet precautions on the incidence of hospital-acquired methicillin-resistant Staphylococcus aureus infection.

OBJECTIVE: To evaluate the efficacy of contact and droplet precautions in reducing the incidence of hospital-acquired methicillin-resistant Staphylococcus aureus (MRSA) infections. DESIGN: Before-after study.Setting. A 439-bed, university-affiliated community hospital. METHODS: To identify inpatients infected or colonized with MRSA, we conducted surveillance of S. aureus isolates recovered from clinical culture and processed by the hospital's clinical microbiology laboratory. We then reviewed patient records for all individuals from whom MRSA was recovered. The rates of hospital-acquired MRSA infection were tabulated for each area where patients received nursing care. After a baseline period, contact and droplet precautions were implemented in all intensive care units (ICUs). Reductions in the incidence of hospital-acquired MRSA infection in ICUs led to the implementation of contact precautions in non-ICU patient care areas (hereafter, "non-ICU areas"), as well. Droplet precautions were discontinued. An analysis comparing the rates of hospital-acquired MRSA infection during different intervention periods was performed. RESULTS: The combined baseline rate of hospital-acquired MRSA infection was 10.0 infections per 1,000 patient-days in the medical ICU (MICU) and surgical ICU (SICU) and 0.7 infections per 1,000 patient-days in other ICUs. Following the implementation of contact and droplet precautions, combined rates of hospital-acquired MRSA infection in the MICU and SICU decreased to 4.3 infections per 1,000 patient-days (95% confidence interval [CI], 0.17-0.97; P=.03). There was no significant change in hospital-acquired MRSA infection rates in other ICUs. After the discontinuation of droplet precautions, the combined rate in the MICU and SICU decreased further to 2.5 infections per 1,000 patient-days. This finding was not significant (P=.43). In the non-ICU areas that had a high incidence of hospital-acquired MRSA infection, the rate prior to implementation of contact precautions was 1.3 infections per 1,000 patient-days. After the implementation of contact precautions, the rate in these areas decreased to 0.9 infections per 1,000 patient-days (95% CI, 0.47-0.94; P=.02). CONCLUSION: The implementation of contact precautions significantly decreased the rate of hospital-acquired MRSA infection, and discontinuation of droplet precautions in the ICUs led to a further reduction. Additional studies evaluating specific infection control strategies are needed.     

To isolate or not to isolate? Analysis of data from the German Nosocomial Infection Surveillance System regarding the placement of patients with methicillin-resistant Staphylococcus aureus in private rooms in intensive care units.

OBJECTIVE: To investigate whether isolating patients with MRSA in private rooms in ICUs (or cohorting) is a protective factor for nosocomial MRSA infection. DESIGN: Association between nosocomial MRSA infection rates and ICU structure and process parameters in the German Nosocomial Infection Surveillance System (KISS). SETTING: Two hundred twelve ICUs participating in KISS in 2001. METHODS: In June 2001, a structured questionnaire was sent to the participating ICUs regarding their preventive measures, their type and size, their patient-to-personnel ratios, and routine cultures. Univariate and multivariate analyses were conducted to identify risk factors for nosocomial MRSA infection. RESULTS: The questionnaire was completed by 164 (77.4%) of the ICUs. These ICUs had 325 nosocomial MRSA infections in a 5-year period (1997 to 2001). The mean incidence density of nosocomial MRSA infections was 0.3/1,000 patient-days. Ninety-one ICUs (55.5%) did not register any nosocomial MRSA infections during the observation period. Forty-two ICUs had an incidence density of at least 0.3/1,000 patient-days (75th percentile). Surgical ICUs were found to be a risk factor for a nosocomial MRSA infection rate above this threshold. Multivariate analysis found surgical ICUs to be an independent predictor and isolation in private rooms (or cohorts) to be a protective factor (OR, 0.36; CI95, 0.17-0.79). CONCLUSION: Many (34.4%) of the German ICUs have not isolated MRSA patients in private rooms or cohorts, a procedure associated with lower MRSA infection rates in this study.     

Temporal changes in bacterial resistance in German intensive care units, 2001-2003: data from the SARI (surveillance of antimicrobial use and antimicrobial resistance in intensive care units) project

Conservative testing revealed a stable antibiotic resistance situation for Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Enterobacter cloacae in 32 German intensive care units (ICUs) actively participating in the SARI (surveillance of antimicrobial use and antimicrobial resistance in ICUs) project over a three-year period (2001--2003). No significant changes were shown for methicillin-resistant S. aureus (MRSA) (P=0.501; the MRSA rate increased in 18 ICUs and decreased in 14 ICUs). The only exception was an increase in ciprofloxacin-resistant E. coli.     

Effect of targeted surveillance for control of methicillin-resistant Staphylococcus aureus in a community hospital system.

OBJECTIVE: To examine the cost associated with targeted surveillance for methicillin-resistant Staphylococcus aureus (MRSA) and the effect of such surveillance on the rate of nosocomial MRSA infection in a community hospital system. DESIGN: A before-and-after study comparing the rate of MRSA infection before (BES) and after (AES) the initiation of expanded surveillance. Cost-effectiveness was calculated as the difference between the cost savings associated with preventing nosocomial MRSA bacteremias and surgical site infections AES and the cost of MRSA cultures and contact isolation for patients colonized with MRSA. SETTING AND PARTICIPANTS: Patients in a 400-bed tertiary-care facility (Roper Hospital) and a 180-bed suburban hospital (St. Francis Hospital), both in Charleston, South Carolina.Interventions. Beginning in September 2001, patients were screened for MRSA colonization upon admission to the intensive care unit and weekly thereafter. In July 2002, surveillance was expanded to include targeted screening of patients admitted to general wards who were at risk of MRSA colonization. Colonized patients were placed in contact isolation. RESULTS: The mean rate of nosocomial MRSA infection decreased at Roper (0.76 cases per 1,000 patient-days BES and 0.45 per 1000 patient-days AES; P = .05) and at St. Francis (0.73 cases per 1,000 patient-days BES and 0.57 cases per 1000 patient-days AES; P=.35). Surveillance was cost-effective, preventing 13 nosocomial MRSA bacteremias and 9 surgical site infections, for a savings of 1,545,762 US dollars. CONCLUSIONS: Targeted surveillance for MRSA colonization was cost-effective and provided substantial benefits by reducing the rate of nosocomial MRSA infections in a community hospital system.     

Surveillance of nosocomial infections in a neurologic intensive care unit.

OBJECTIVE: To assess data on the epidemiology of nosocomial infection (NI) among neurologic intensive care patients. DESIGN: Prospective periodic surveillance study. SETTING: An 8-bed neurologic intensive care unit (ICU). PATIENTS: All those admitted for more than 24 hours during five 3-month periods between January 1999 and March 2003. METHODS: Standardized surveillance within the German infection surveillance system. RESULTS: Three hundred thirty-eight patients with a total of 2,867 patient-days and a mean length of stay of 8.5 days were enrolled during the 15-month study period. A total of 71 NIs were identified among 52 patients. Urinary tract infections (UTIs) were the most frequent NI (36.6%), followed by pneumonia (29.6%) and bloodstream infections (BSIs) (15.5%). The overall incidence and incidence density of NIs were 21.0 per 100 patients and 24.8 per 1,000 patient-days, respectively. Incidence densities were 9.8 UTIs per 1,000 urinary catheter-days (CI95, 6.4-14.4), 5.6 BSIs per 1,000 central venous catheter-days (CI9s, 2.8-10.0), and 12.8 cases of pneumonia per 1,000 ventilation-days (Cl95, 8.0-19.7). Device-associated UTI and pneumonia rates were in the upper range of national and international reference data for medical ICUs, despite the intensive infection control and prevention program in operation in the hospital. CONCLUSION: Neurologic intensive care patients have relatively high rates of device-associated nosocomial pneumonia and UTI. For a valid comparison of surveillance data and implementation of targeted prevention strategies, we would strongly recommend provision of national benchmarks for the neurologic ICU setting.     

Selective use of intranasal mupirocin and chlorhexidine bathing and the incidence of methicillin-resistant Staphylococcus aureus colonization and infection among intensive care unit patients.

OBJECTIVE: To determine whether the use of chlorhexidine bathing and intranasal mupirocin therapy among patients colonized with methicillin-resistant Staphylococcus aureus (MRSA) would decrease the incidence of MRSA colonization and infection among intensive care unit (ICU) patients. METHODS: After a 9-month baseline period (January 13, 2003, through October 12, 2003) during which all incident cases of MRSA colonization or infection were identified through the use of active-surveillance cultures in a combined medical-coronary ICU, all patients colonized with MRSA were treated with intranasal mupirocin and underwent daily chlorhexidine bathing. RESULTS: After the intervention, incident cases of MRSA colonization or infection decreased 52% (incidence density, 8.45 vs 4.05 cases per 1,000 patient-days; P=.048). All MRSA isolates remained susceptible to chlorhexidine; the overall rate of mupirocin resistance was low (4.4%) among isolates identified by surveillance cultures and did not increase during the intervention period. CONCLUSIONS: We conclude that the selective use of intranasal mupirocin and daily chlorhexidine bathing for patients colonized with MRSA reduced the incidence of MRSA colonization and infection and contributed to reductions identified by active-surveillance cultures. This finding suggests that additional strategies to reduce the incidence of MRSA infection and colonization--beyond expanded surveillance--may be needed.     

How many nosocomial infections are associated with cross-transmission? A prospective cohort study in a surgical intensive care unit.

OBJECTIVE: To determine the percentage of cross-transmissions in an intensive care unit (ICU) with high nosocomial infection (NI) rates according to the data of the German Nosocomial Infection Surveillance System. SETTING: A 14-bed surgical ICU of a 1,300-bed, tertiary-care teaching hospital. METHOD: Prospective surveillance of NIs during a period of 9 months. If an NI was present, the isolates of the following indicator pathogens were stored and typed by species: Staphylococcus aureus, Enterococcus species, Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, and Enterobacter species. Pulsed-field gel electrophoresis was performed for typing of S. aureus strains and arbitrarily primed polymerase chain reaction was applied for the other pathogens. The presence of two indistinguishable strains in two patients was considered as one episode of cross-transmission. RESULTS: Two hundred sixty-two patients were observed during a period of 2,444 patient-days; 96 NIs were identified in 59 patients and the overall incidence density of NI was 39.3 per 1,000 patient-days. For 104 isolates, it was possible to consider typing results. Altogether, 36 cross-transmissions have lead to NIs in other patients. That means at least 37.5% of all NIs identified were due to cross-transmissions. CONCLUSION: Because of the method of this study, the percentage of NIs due to cross-transmission identified for this ICU is an "at least number." In reality, the number of cross-transmissions, and thus the number of avoidable infections, may have been even higher. However, it is difficult to assess whether the percentage of NIs due to cross-transmission determined for this ICU may be the crucial explanation for the relatively high infection rate in comparison to other surgical ICUs.     

Active screening in high-risk units is an effective and cost-avoidant method to reduce the rate of methicillin-resistant Staphylococcus aureus infection in the hospital.

OBJECTIVE: To evaluate the impact of active screening for methicillin-resistant Staphylococcus aureus (MRSA) on MRSA infection rates and cost avoidance in units where the risk of MRSA transmission is high. METHODS: During a 15-month period, all patients admitted to our adult medical and surgical intensive care units (ICUs) were screened for MRSA nasal carriage on admission and weekly thereafter. The overall rates of all MRSA infections and of nosocomial MRSA infection in the 2 adult ICUs and the general wards were compared with rates during the 15-month period prior to the start of routine screening. The percentage of patients colonized or infected with MRSA on admission and the cost avoidance of the surveillance program were also assessed. RESULTS: The overall rate of MRSA infections for all 3 areas combined decreased from 6.1 infections per 1,000 census-days in the preintervention period to 4.1 infections per 1,000 census-days in the postintervention period (P = .01). The decrease remained statistically significant when only nosocomial MRSA infections were examined (4.5 vs 2.8 infections per 1,000 census-days; P < .01), despite a corresponding increase during the postintervention period in the percentage of patients with onset of MRSA infection in the first 72 hours after admission to the general wards (46% to 81%; P < .005). A total of 3.7% of ICU patients were colonized or infected with MRSA on admission; MRSA would not have been detected in 91% of these patients if screening had not been performed. At a cost of Dollars 3,475/month for the program, we averted a mean of 2.5 MRSA infections/month for the ICUs combined, avoiding Dollars 19,714/month in excess cost in the ICUs. CONCLUSIONS: Even in a setting of increasing community-associated MRSA, active MRSA screening as part of a multi-factorial intervention targeted to high-risk units may be an effective and cost-avoidant strategy for achieving a sustained decrease of MRSA infections throughout the hospital.     

Epidemiology of nosocomial bacterial infections in a neonatal and pediatric Tunisian intensive care unit

OBJECTIVE: The authors had for aim to describe the epidemiology of nosocomial bacterial infections in the neonatal and pediatric intensive care unit of the Tunis children's hospital. DESIGN: A prospective surveillance study was made from January 2004 to December 2004. All patients remaining in the intensive care unit for more than 48 h were included. CDC criteria were applied for the diagnosis of nosocomial infections. RESULTS: 340 patients including 249 (73%) neonates were included. 22 patients presented with 22 nosocomial bacterial infections. The incidence and the density incidence rates of nosocomial bacterial infections were 6.5% and 7.8 per 1,000 patient-days, respectively. Two types of infection were found: bloodstream infections (68.2%) and pneumonias (22.7%). Bloodstream infections had an incidence and a density incidence rate of 4.4% and 15.3 per 1,000 catheter-days, respectively. Pneumonia had an incidence and a density incidence rate of 2% and 4.4 per 1,000 mechanical ventilation-days, respectively. The most frequently isolated pathogens were Gram-negative bacteria (68%) with Klebsiella pneumoniae isolates accounting for 22.7%. The most common isolate in bloodstream infections was K. Pneumoniae (26.7%), which was multiple drug-resistant in 85% of the cases, followed by Staphylococcus aureus (20%). Pseudomonas aeruginosa was the most common isolate in pneumonia (28.6%). Associated factors of nosocomial infection were invasive devices and colonization with multiple drug-resistant Gram-negative bacteria. CONCLUSIONS: The major type of nosocomial bacterial infections in our unit was bloodstream infection and the majority of infections resulted from Gram-negative bacteria. Factors associated with nosocomial bacterial infections were identified in our unit.     

Relationship between rates of antimicrobial consumption and the incidence of antimicrobial resistance in Staphylococcus aureus and Pseudomonas aeruginosa isolates from 47 French hospitals.

OBJECTIVE: To investigate relationships between rates of antimicrobial consumption and the incidence of antimicrobial resistance in Staphylococcus aureus and Pseudomonas aeruginosa isolates from hospitals. METHODS: We conducted an observational study that used retrospective data from 2002 and linear regression to model relationships. Hospitals were asked to collect data on consecutive S. aureus and P. aeruginosa isolates, consumption rates for antibiotics (ie, anti-infectives for systemic use as defined by Anatomical Therapeutic Chemical class J01), and hospital characteristics, including infection control policies. Rates of methicillin resistance in S. aureus and rates of ceftazidime and ciprofloxacin resistance in P. aeruginosa were expressed as the percentage of isolates that were nonsusceptible (ie, either resistant or intermediately susceptible) and as the incidence of nonsuceptible isolates (ie, the number of nonsuceptible isolates recovered per 1,000 patient-days). The rate of antimicrobial consumption was expressed as the number of defined daily doses per 1,000 patient-days. SETTING: Data were obtained from 47 French hospitals, and a total of 12,188 S. aureus isolates and 6,370 P. aeruginosa isolates were tested. RESULTS: In the multivariate analysis, fewer antimicrobials showed a significant association between the consumption rate and the percentage of isolates that were resistant than an association between the consumption rate and the incidence of resistance. The overall rate of antibiotic consumption, not including the antibiotics used to treat methicillin-resistant S. aureus infection, explained 13% of the variance between hospitals in the incidence of methicillin resistance among S. aureus isolates. The incidence of methicillin resistance in S. aureus isolates increased with the use of ciprofloxacin and levofloxacin and with the percentage of the hospital's beds located in intensive care units (adjusted multivariate coefficient of determination [aR(2)], 0.30). For P. aeruginosa, the incidence of ceftazidime resistance was greater in hospitals with higher consumption rates for ceftazidime, levofloxacin, and gentamicin (aR(2), 0.37). The incidence of ciprofloxacin resistance increased with the use of fluoroquinolones and with the percentage of a hospital's beds located in intensive care ( aR(2), 0.28). CONCLUSIONS: A statistically significant relationship existed between the rate of fluoroquinolone use and the rate of antimicrobial resistance among S. aureus and P. aeruginosa isolates. The incidence of resistant isolates showed a stronger association with the rate of antimicrobial use than did the percentage of isolates with resistance.     

Genodiversity of resistant Pseudomonas aeruginosa isolates in relation to antimicrobial usage density and resistance rates in intensive care units.

OBJECTIVE: To evaluate the assumption that resistance rates in intensive care units (ICUs) are markedly influenced by cross-transmission events in addition to high rates of antimicrobial usage. METHODS: This was a prospective ICU- and laboratory-based surveillance study involving 35 German ICUs from 1999 through 2004. A total of 585 ciprofloxacin- or imipenem-resistant isolates of Pseudomonas aeruginosa were investigated together with resistance rate and unit-based antimicrobial usage density. Antimicrobial use was reported in terms of defined daily doses per 1,000 patient-days. All the strains were assigned to ICU-based genotypes. Genodiversity was calculated as the numbers of indistinguishable ICU-based genotypes found per isolates tested. Reduced ICU-based genodiversity was taken as an indirect measure of frequently occurring cross-transmission events. RESULTS: The genodiversity of ciprofloxacin- and imipenem-resistant P. aeruginosa isolates was significantly lower ([Formula: see text], by Fisher exact test) in ICUs with high resistance rate and low antimicrobial usage density (genodiversity, 0.50 and 0.50, respectively) than in ICUs that featured low resistance rate in the presence of high antimicrobial usage density (genodiversity, 0.90 and 0.95, respectively). In ICUs with low genodiversity, there was a greater rise in resistance rate with increasing antimicrobial usage density, compared with that in ICUs with high diversity. CONCLUSIONS: This study on resistant P. aeruginosa isolates supports the assumption that high resistance rate in the presence of low antimicrobial usage density results from more-frequent cross-transmission events. A greater rise in resistance rate with increasing antimicrobial usage density in ICUs with low genodiversity indicates that resistance rate in ICUs might be markedly determined by cross-transmission events other than antimicrobial usage.     

Regional trends in multidrug-resistant infections in German intensive care units: a real-time model for epidemiological monitoring and analysis

A new surveillance module for multidrug-resistant (MDR) bacteria was added to the intensive care component of the German Nosocomial Infection Surveillance System. Participating intensive care units (ICUs) report data on all patients colonised or infected with meticillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE) and extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae (ESBL-EC/KP). To determine the regional distribution of MRSA, VRE and ESBL-EC/KP in Germany, incidence densities (IDs) of these bacteria per 1000 patient-days were calculated for each ICU and pooled for ICUs of five German regions for the years 2005 and 2006. A total of 176 ICUs including 284 142 patients and 1 021 579 patient-days reported data concerning 5490 cases of MDR bacteria. The pooled IDs were 4.54, 0.54 and 0.29 cases per 1000 patient-days for MRSA, ESBL-EC/KP and VRE cases and 1.56, 0.32 and 0.13 per 1000 patient-days for MRSA, ESBL-EC/KP and VRE infections, respectively. While there were no significant differences in the incidence densities of MRSA infections between regions, the IDs of VRE and ESBL-EC/KP infections showed significant regional variation. The regions also differed in the proportion of ICUs per region that reported at least one infection with MRSA, ESBL-EC/KP or VRE in 2005–2006 and these differences ranged from 82% to 91% for MRSA, from 34% to 76% for ESBL-EC/KP and from 8% to 42% for VRE. This new surveillance module enables ICUs to monitor the occurrence of MDR bacteria by comparing local incidence densities with a national reference and shows significant regional variation of MDR bacteria in Germany.     

Five-year surveillance of nosocomial infections in Ankara Training and Research Hospital

The objective of this study was to assess the rate of nosocomial infections (NIs), frequency of nosocomial pathogens and antimicrobial susceptibility changes in a 530-bed hospital over a five-year period. Hospital-wide laboratory-based NI surveillance was performed prospectively between 1999 and 2003. The Centers for Disease Control and Prevention's definitions were used for NIs and nosocomial surgical site infections, and NI rates were calculated by the number of NIs per number of hospitalized patients on an annual basis. NI rates ranged between 1.4% and 2.4%. Higher rates were observed in the neurology, neurosurgery, paediatric and dermatology departments; the low rate of NIs overall may be due to the surveillance method used. The most commonly observed infections were urinary tract, surgical site and primary bloodstream infections, and the most frequently isolated pathogens were Escherichia coli, Klebsiella pneumoniae, Enterococcus spp. and Staphylococcus aureus. Carbapenems were the most effective agents against enterobacteriaceae. Meticillin resistance among S. aureus isolates was less than 50%, and all S. aureus and Enterococcus spp. isolates were susceptible to glycopeptides apart from one glycopeptide-resistant E. faecium isolate identified in 2003. Data obtained by the same method enabled comparison between years and assisted in the detection of recent changes. Antimicrobial susceptibility data on nosocomial pathogens provided valuable guidance for empirical antimicrobial therapy of NIs.     

Impact of alcohol-based, waterless hand antiseptic on the incidence of infection and colonization with methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci.

OBJECTIVE: Colonized and infected inpatients are major reservoirs for methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE), and transient carriage of these pathogens on the hands of healthcare workers remains the most common mechanism of patient-to-patient transmission. We hypothesized that use of alcohol-based, waterless hand antiseptic would lower the incidence of colonization and/or infection with MRSA and VRE. METHODS: On June 19, 2001, alcohol hand antiseptic was introduced at the University campus and not the nearby Memorial campus of the University of Massachusetts Medical School (Worcester, MA), allowing us to evaluate the impact of this antiseptic on the incidence of MRSA and VRE colonization and infection. From January 1 through December 31, 2001, the incidence of MRSA colonization or infection was compared between the 2 campuses before and after the hand antiseptic was introduced. Its effect on VRE colonization and infection was only studied in the medical intensive care unit at the University campus. RESULTS: At the University campus, the incidence of MRSA colonization or infection decreased from 1.26 cases/1,000 patient-days before the intervention to 0.75 cases/1,000 patient-days after the intervention, for a 1.46-fold decrease (95% confidence interval, 1.04-2.58; P = .037). At the Memorial campus, the incidence of MRSA colonization or infection remained virtually unchanged, from 0.34 cases/1,000 patient-days to 0.49 cases/1,000 patient-days during the same period. However, a separate analysis of the University campus data that controlled for proximity to prevalent cases did not show a significant improvement in the rates of infection or colonization. The incidence of nosocomial VRE colonization or infection before and after the hand antiseptic decreased from 12.0 cases/1,000 patient-days to 3.0 cases/1,000 patient-days, a 2.25-fold decrease (P = .018). Compliance with rectal surveillance for detection of VRE was 86% before and 84% after implementation of the hand antiseptic intervention. The prevalences of VRE cases during these 2 periods were 25% and 29%, respectively (P = .017). CONCLUSIONS: Alcohol hand antiseptic appears to be effective in controlling the transmission of VRE. However, after controlling for proximity to prevalent cases (ie, for clustering), it does not appear to be more effective than standard methods for controlling MRSA. Further controlled studies are needed to evaluate its effectiveness.     

Device-associated nosocomial infection rates in Turkish medical-surgical intensive care units.

OBJECTIVE: To describe the incidence of device-associated nosocomial infections in medical-surgical intensive care units (MS ICUs) in a university hospital in Turkey and compare it with National Nosocomial Infections Surveillance (NNIS) system rates. DESIGN: Prospective surveillance study during a period of 27 months. Device utilization ratios and device-associated infection rates were calculated using US Centers for Disease Control and Prevention and NNIS definitions. SETTING: Two separate MS ICUs at Akdeniz University Hospital, Antalya, Turkey. PATIENTS: All patients were included who presented with no signs and symptoms of infection within the first 48 hours after admission. RESULTS: Data on 1,985 patients with a total of 16,892 patient-days were analyzed. The mean overall infection rate per 100 patients was 29.1 infections, and the mean infection rate per 1,000 patient-days was 34.2 infections. The rate of ventilator-associated pneumonia was 20.76 infections per 1,000 ventilator-days, the rate of catheter-associated urinary tract infection was 13.63 infections per 1,000 urinary catheter-days, and the rate of catheter-associated bloodstream infection was 9.69 infections per 1,000 central line-days. The most frequently isolated pathogens were Pseudomonas species among patients with ventilator-associated pneumonias (35.8% of cases), Candida species among patients with catheter-associated urinary tract infections (37.1% of cases), and coagulase-negative staphylococci among patients with catheter-associated bloodstream infections (20.0% of cases). CONCLUSION: We found both higher device-associated infection rates and higher device utilization ratios in our MS ICUs than those reported by the NNIS system. To reduce the rate of infection, implementation of infection control practices and comprehensive education are required, and an appropriate nationwide nosocomial infection and control system is needed in Turkey.     

Are there regional variations in the diagnosis, surveillance, and control of methicillin-resistant Staphylococcus aureus?

OBJECTIVE: To assess the way healthcare facilities (HCFs) diagnose, survey, and control methicillin-resistant Staphylococcus aureus (MRSA). DESIGN: Questionnaire. SETTING: Ninety HCFs in 30 countries. RESULTS: Evaluation of susceptibility testing methods showed that 8 laboratories (9%) used oxacillin disks with antimicrobial content different from the one recommended, 12 (13%) did not determine MRSA susceptibility to vancomycin, and 4 (4.5%) reported instances of isolation of vancomycin-resistant S. aureus but neither confirmed this resistance nor alerted public health authorities. A MRSA control program was reported by 55 (61.1%) of the HCFs. The following isolation precautions were routinely used: hospitalization in a private room (34.4%), wearing of gloves (62.2%), wearing of gowns (44.4%), hand washing by healthcare workers (53.3%), use of an isolation sign on the patient's door (43%), or all four. When the characteristics of HCFs with low incidence rates (< 0.4 per 1,000 patient-days) were compared with those of HCFs with high incidence rates (> or = 0.4 per 1,000 patient-days), having a higher mean number of beds per infection control nurse was the only factor significantly associated with HCFs with high incidence rates (834 vs 318 beds; P = .02). CONCLUSION: Our results emphasize the urgent need to strengthen the microbiologic and epidemiologic capacities of HCFs worldwide to prevent MRSA transmission and to prepare them to address the possible emergence of vancomycin-resistant S. aureus.     

Device-associated nosocomial infection rates in intensive care units of Argentina.

BACKGROUND: Nosocomial infections are an important public health problem in many developing countries, particularly in the intensive care unit (ICU) setting. No previous data are available on the incidence of device-associated nosocomial infections in different types of ICUs in Argentina. METHODS: We performed a prospective nosocomial infection surveillance study during the first year of an infection control program in six Argentinean ICUs. Nosocomial infections were identified using the Centers for Disease Control and Prevention National Nosocomial Infections Surveillance System definitions, and site-specific nosocomial infection rates were calculated. RESULTS: The rate of catheter-associated bloodstream infections in medical-surgical ICUs was 30.3 per 1,000 device-days; it was 14.2 per 1,000 device-days in coronary care units (CCUs). The rate of ventilator-associated pneumonia in medical-surgical ICUs was 46.3 per 1,000 device-days; it was 45.5 per 1,000 device-days in CCUs. The rate of symptomatic catheter-associated urinary tract infections in medical-surgical ICUs was 18.5 per 1,000 device-days; it was 12.1 per 1,000 device-days in CCUs. CONCLUSION: The high rate of nosocomial infections in Argentinean ICUs found during our surveillance suggests that ongoing targeted surveillance and implementation of proven infection control strategies is needed in developing countries such as Argentina.     

Intensive care unit outbreak of extended-spectrum beta-lactamase-producing Klebsiella pneumoniae controlled by cohorting patients and reinforcing infection control measures.

OBJECTIVE: To describe an outbreak of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae in the intensive care units (ICUs) of a hospital and the impact of routine and reinforced infection control measures on interrupting nosocomial transmission. DESIGN: Outbreak report. SETTING: A 31-bed intensive care department (composed of 4 ICUs) in a university hospital in Belgium. INTERVENTION: After routine infection control measures (based on biweekly surveillance cultures and contact precautions) failed to interrupt a 2-month outbreak of ESBL-producing K. pneumoniae, reinforced infection control measures were implemented. The frequency of surveillance cultures was increased to daily sampling. Colonized patients were moved to a dedicated 6-bed ICU, where they received cohorted care with the support of additional nurses. Two beds were closed to new admissions in the intensive care department. Meetings between the ICU and infection control teams were held every day. Postdischarge disinfection of rooms was enforced. Broad-spectrum antibiotic use was discouraged. RESULTS: Compared with a baseline rate of 0.44 cases per 1,000 patient-days for nosocomial transmission, the incidence peaked at 11.57 cases per 1,000 patient-days (October and November 2005; rate ratio for peak vs baseline, 25.46). The outbreak involved 30 patients, of whom 9 developed an infection. Bacterial genotyping disclosed that the outbreak was polyclonal, with 1 predominant genotype. Reinforced infection control measures lasted for 50 days. After the implementation of these measures, the incidence fell to 0.08 cases per 1,000 patient-days (rate ratio for after the outbreak vs during the outbreak, 0.11). CONCLUSION: These data indicate that, in an intensive care department in which routine screening and contact precautions failed to prevent and interrupt an outbreak of ESBL-producing K. pneumoniae, reinforced infection control measures controlled the outbreak without major disruption of medical care.