Effect of statin therapy in the outcome of bloodstream infections due to Staphylococcus aureus: a prospective cohort study.

INTRODUCTION: Statins have pleiotropic effects that could influence the prevention and outcome of some infectious diseases. There is no information about their specific effect on Staphylococcus aureus bacteremia (SAB). METHODS: A prospective cohort study including all SAB diagnosed in patients aged ≥18 years admitted to a 950-bed tertiary hospital from March 2008 to January 2011 was performed. The main outcome variable was 14-day mortality, and the secondary outcome variables were 30-day mortality, persistent bacteremia (PB) and presence of severe sepsis or septic shock at diagnosis of SAB. The effect of statin therapy at the onset of SAB was studied by multivariate logistic regression and Cox regression analysis, including a propensity score for statin therapy. RESULTS: We included 160 episodes. Thirty-three patients (21.3%) were receiving statins at the onset of SAB. 14-day mortality was 21.3%. After adjustment for age, Charlson index, Pitt score, adequate management, and high risk source, statin therapy had a protective effect on 14-day mortality (adjusted OR = 0.08; 95% CI: 0.01-0.66; p = 0.02), and PB (OR = 0.89; 95% CI: 0.27-1.00; p = 0.05) although the effect was not significant on 30-day mortality (OR = 0.35; 95% CI: 0.10-1.23; p = 0.10) or presentation with severe sepsis or septic shock (adjusted OR = 0.89; CI 95%: 0.27-2.94; p = 0.8). An effect on 30-day mortality could neither be demonstrated on Cox analysis (adjusted HR = 0.5; 95% CI: 0.19-1.29; p = 0.15). CONCLUSIONS: Statin treatment in patients with SAB was associated with lower early mortality and PB. Randomized studies are necessary to identify the role of statins in the treatment of patients with SAB.

Impact of an evidence-based bundle intervention in the quality-of-care management and outcome of Staphylococcus aureus bacteremia.

BACKGROUND: Staphylococcus aureus bacteremia (SAB) is associated with significant morbidity and mortality. Several aspects of clinical management have been shown to have significant impact on prognosis. The objective of the study was to identify evidence-based quality-of-care indicators (QCIs) for the management of SAB, and to evaluate the impact of a QCI-based bundle on the management and prognosis of SAB. METHODS: A systematic review of the literature to identify QCIs in the management of SAB was performed. Then, the impact of a bundle including selected QCIs was evaluated in a quasi-experimental study in 12 tertiary Spanish hospitals. The main and secondary outcome variables were adherence to QCIs and mortality. Specific structured individualized written recommendations on 6 selected evidence-based QCIs for the management of SAB were provided. RESULTS: A total of 287 and 221 patients were included in the preintervention and intervention periods, respectively. After controlling for potential confounders, the intervention was independently associated with improved adherence to follow-up blood cultures (odds ratio [OR], 2.83; 95% confidence interval [CI], 1.78-4.49), early source control (OR, 4.56; 95% CI, 2.12-9.79), early intravenous cloxacillin for methicillin-susceptible isolates (OR, 1.79; 95% CI, 1.15-2.78), and appropriate duration of therapy (OR, 2.13; 95% CI, 1.24-3.64). The intervention was independently associated with a decrease in 14-day and 30-day mortality (OR, 0.47; 95% CI, .26-.85 and OR, 0.56; 95% CI, .34-.93, respectively). CONCLUSIONS: A bundle orientated to improving adherence to evidence-based QCIs improved the management of patients with SAB and was associated with reduced mortality.

Long-term control of endemic hospital-wide methicillin-resistant Staphylococcus aureus (MRSA): the impact of targeted active surveillance for MRSA in patients and healthcare workers.

OBJECTIVE: To evaluate the long-term impact of successive interventions on rates of methicillin-resistant Staphylococcus aureus (MRSA) colonization or infection and MRSA bacteremia in an endemic hospital-wide situation. DESIGN: Quasi-experimental, interrupted time-series analysis. The impact of the interventions was analyzed by use of segmented regression. Representative MRSA isolates were typed by use of pulsed-field gel electrophoresis. SETTING: A 950-bed teaching hospital in Seville, Spain. PATIENTS: All patients admitted to the hospital during the period from 1995 through 2008. METHODS: Three successive interventions were studied: (1) contact precautions, with no active surveillance for MRSA; (2) targeted active surveillance for MRSA in patients and healthcare workers in specific wards, prioritized according to clinical epidemiology data; and (3) targeted active surveillance for MRSA in patients admitted from other medical centers. RESULTS: Neither the preintervention rate of MRSA colonization or infection (0.56 cases per 1,000 patient-days [95% confidence interval {CI}, 0.49-0.62 cases per 1,000 patient-days]) nor the slope for the rate of MRSA colonization or infection changed significantly after the first intervention. The rate decreased significantly to 0.28 cases per 1,000 patient-days (95% CI, 0.17-0.40 cases per 1,000 patient-days) after the second intervention and to 0.07 cases per 1,000 patient-days (95% CI, 0.06-0.08 cases per 1,000 patient-days) after the third intervention, and the rate remained at a similar level for 8 years. The MRSA bacteremia rate decreased by 80%, whereas the rate of bacteremia due to methicillin-susceptible S. aureus did not change. Eighty-three percent of the MRSA isolates identified were clonally related. All MRSA isolates obtained from healthcare workers were clonally related to those recovered from patients who were in their care. CONCLUSION: Our data indicate that long-term control of endemic MRSA is feasible in tertiary care centers. The use of targeted active surveillance for MRSA in patients and healthcare workers in specific wards (identified by means of analysis of clinical epidemiology data) and the use of decolonization were key to the success of the program.

Long-term control of hospital-wide, endemic multidrug-resistant Acinetobacter baumannii through a comprehensive "bundle" approach.

BACKGROUND: Acinetobacter baumannii (Ab) is emerging as a multidrug-resistant (MDR) nosocomial pathogen of considerable clinical importance. Data on the efficacy of infection control measures in endemic situations are lacking. Here, we investigated the impact of a long-term multifaceted "bundle" approach in controlling endemic MDR Ab in a 950-bed tertiary care center. METHODS: Ongoing staff education, promotion of hand hygiene, strict Contact and Isolation Precautions, environmental cleaning, and targeted active surveillance in high-risk areas during periods of likely transmission and contamination were initiated in this program. To assess the efficacy of our interventions, we recorded (before and after the intervention) the epidemiologic and clinical features of MDR Ab infections and determined the clonal relationship among MDR Ab bloodstream isolates by pulsed-field gel electrophoresis. RESULTS: Before the "bundle" was instituted, the rate of colonization/infection was 0.82 cases per 100 admissions (1994-1995). Colonization/infection rates showed a sustained decrease after implementation of the control program in 1995 to 0.46 in 1996-1997 and to 0.21 in 1998-2003 (P < .001). Coincident with the institution of this program, the rate of bacteremia because of MDR Ab decreased 6-fold during the 8-year observation period. A notable change in the clonal distribution of the MDR Ab isolates was also demonstrated. CONCLUSION: The implementation of a comprehensive and multifaceted infection control program ("bundle") in a tertiary care center effectively controlled the spread and clinical impact of MDR Ab.

Molecular screening of Bartonella species in rodents from south western Spain.

Rodents (87 Mus spretus and 10 Rattus norvegicus) collected in a suburban area of Seville (Andalusia, Spain) between September 2003 and April 2004 were tested by polymerase chain reaction for the presence of Bartonella DNA using primers amplifying a fragment of the 16S/23S rRNA internal transcribed spacer (ITS). Sequence analyses of the ITS of these Bartonella demonstrated that rodents in this region harbored at least three strains: two Bartonella genotypes detected in M. spretus, which clustered separately, and one genotype corresponding with B. tribocorum in R. norvegicus. The finding of Bartonella species in a high proportion of the rodent samples suggests the need to investigate whether these agents might be responsible for cases of febrile illnesses of unknown etiology in Southern Spain.

Bacteremia due to extended-spectrum beta -lactamase-producing Escherichia coli in the CTX-M era: a new clinical challenge.

BACKGROUND: Extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli, particularly those producing CTX-M types of ESBL, are emerging pathogens. Bacteremia caused by these organisms represents a clinical challenge, because the organisms are frequently resistant to the antimicrobials recommended for treatment of patients with suspected E. coli sepsis. METHODS: A cohort study was performed that included all episodes of bloodstream infection due to ESBL-producing E. coli during the period from January 2001 through March 2005. Data on predisposing factors, clinical presentation, and outcome were collected. ESBLs were characterized using isoelectric focusing, polymerase chain reaction, and sequencing. RESULTS: Forty-three episodes (8.8% of cases of bacteremia due to E. coli) were included; 70% of the isolates produced a CTX-M type of ESBL. The most frequent origins of infection were the urinary (46%) and biliary tracts (21%). Acquisition was nosocomial in 21 cases (49%), health care associated in 14 cases (32%), and strictly community acquired in 8 cases (19%). Thirty-eight percent and 25% of patients had obstructive diseases of the urinary and biliary tracts, respectively, and 38% had recently received antimicrobials. Nine patients (21%) died. Compared with beta-lactam/beta-lactamase-inhibitor and carbapenem-based regimens, empirical therapy with cephalosporins or fluoroquinolones was associated with a higher mortality rate (9% vs. 35%; P=.05) and needed to be changed more frequently (24% vs. 78%; P=.001). CONCLUSIONS: ESBL-producing E. coli is a significant cause of bloodstream infection in hospitalized and nonhospitalized patients in the context of the emergence of CTX-M enzymes. Empirical treatment of sepsis potentially caused by E. coli may need to be reconsidered in areas where such ESBL-producing isolates are present.

Clinical and molecular epidemiology of extended-spectrum beta-lactamase-producing Escherichia coli as a cause of nosocomial infection or colonization: implications for control.

BACKGROUND: Extended-spectrum beta-lactamase (ESBL)-producing members of the Enterobacteriaceae family are important nosocomial pathogens. Escherichia coli producing a specific family of ESBL (the CTX-M enzymes) are emerging worldwide. The epidemiology of these organisms as causes of nosocomial infection is poorly understood. The aims of this study were to investigate the clinical and molecular epidemiology of nosocomial infection or colonization due to ESBL-producing E. coli in hospitalized patients, consider the specific types of ESBLs produced, and identify the risk factors for infection and colonization with these organisms. METHODS: All patients with nosocomial colonization and/or infection due to ESBL-producing E. coli in 2 centers (a tertiary care hospital and a geriatric care center) identified between January 2001 and May 2002 were included. A double case-control study was performed. The clonal relatedness of the isolates was studied by repetitive extragenic palindromic-polymerase chain reaction and pulsed-field gel electrophoresis. ESBLs were characterized by isoelectric focusing, polymerase chain reaction, and sequencing. RESULTS: Forty-seven case patients were included. CTX-M-producing E. coli were clonally unrelated and more frequently susceptible to nonoxyimino-beta-lactams. Alternately, isolates producing SHV- and TEM-type ESBL were epidemic and multidrug resistant. Urinary catheterization was a risk factor for both CTX-M-producing and SHV-TEM-producing isolates. Previous oxyimino-beta-lactam use, diabetes, and ultimately fatal or nonfatal underlying diseases were independent risk factors for infection or colonization with CTX-M-producing isolates, whereas previous fluoroquinolone use was associated with infection or colonization with SHV-TEM-producing isolates. CONCLUSIONS: The epidemiology of ESBL-producing E. coli as a cause of nosocomial infection is complex. Sporadic CTX-M-producing isolates coexisted with epidemic multidrug-resistant SHV-TEM-producing isolates. These data should be taken into account for the design of control measures.

Epidemiology and clinical features of infections caused by extended-spectrum beta-lactamase-producing Escherichia coli in nonhospitalized patients.

Infections due to extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (ESBLEC) in nonhospitalized patients seem to be emerging in different countries. Their incidence, epidemiology, and clinical impact in the community have not been studied. We describe the epidemiology and clinical features of infections caused by ESBLEC in nonhospitalized patients in Spain and the results of a case-control study performed to investigate the risk factors associated with the acquisition of these organisms. The clonal relatedness of the organisms was assessed by repetitive extragenic palindromic sequence PCR. The ESBLs and the genes encoding the ESBLs were initially characterized by isoelectric focusing and PCR, respectively. Forty-nine patients (76% with urinary tract infections, 22% with asymptomatic bacteriuria, and 2% with acute cholangitis) were included. Six patients were bacteremic. Diabetes mellitus (odds ratio, 5.5; 95% confidence interval, 1.6 to 18.7), previous fluoroquinolone use (odds ratio, 7.6; 95% confidence interval, 1.9 to 30.1), recurrent urinary tract infections (odds ratio, 4.5; 95% confidence interval, 1.3 to 15.1), a previous hospital admission (odds ratio, 18.2; 95% confidence interval, 5.3 to 61.1), and older age in male patients (odds ratio per year, 1.03; 95% confidence interval, 1.03 to 1.05) were identified as risk factors by multivariate analysis. The ESBLEC isolates were not clonally related. The ESBLs were characterized as members of the CTX-M-9 group, the SHV group, and the TEM group in 64, 18, and 18% of the isolates, respectively. ESBLEC is an emergent cause of urinary tract infections in nonhospitalized patients. There was no evidence of horizontal transmission of ESBLEC strains. Avoidance of fluoroquinolone use in high-risk patients should be considered whenever possible in order to avoid the selection of these organisms.

Presence of Rickettsia felis in the cat flea from southwestern Europe.

Rickettsia felis, formerly called ELB agent, was identified by using molecular biology techniques in the cat flea (Ctenocephalides felis felis) from southwestern Spain. For the first time this flea-transmitted rickettsia has been detected within its vector in Eurasia.