Risk Factors, Length of Stay and In-Hospital Mortality of Methicillin-Resistant Staphylococcus aureus Infections: A Case-Control Study

The emergence of strains of methicillin-resistant Staphylococcus aureus is a serious therapeutic challenge in healthcare provision. With this study, we aimed to investigate the risk factors and clinical outcomes (mortality and length of hospital stay) associated with methicillin-resistant Staphylococcus aureus infections in patients admitted to a district hospital in Portugal.info:eu-repo/semantics/publishedVersio

Predictors of Clinical Success Among a National Veterans Affairs Cohort With Methicillin-Resistant Staphylococcus aureus Pneumonia

Background: The treatment of methicillin-resistant Staphylococcus aureus (MRSA) pneumonia is exceedingly complicated, which is concerning because of the high mortality rate associated with the infection. Identification of independent predictors of clinical success can optimize patient care by assisting clinicians in treatment decisions. Objectives: We sought to identify independent predictors of clinical success in a national Veterans Affairs (VA) cohort of MRSA pneumonia patients. Methods: A nested case-control study was conducted among a cohort of VA patients with MRSA pneumonia receiving linezolid or vancomycin between January 2002 and September 2010. Cases included those demonstrating clinical success, defined as discharge from the hospital or intensive care unit (ICU) by day 14 after treatment initiation, in the absence of death, therapy change, or intubation by day 14. Controls represented non-success, defined as therapy change, intubation, ICU admission, re-admission, or death between treatment initiation and day 14. The potential predictors assessed included treatment, patient demographics and admission characteristics, previous healthcare and medication exposures, comorbidities, and medical history. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated from logistic regression. Results: Our study included 2442 cases of clinical success and 1290 controls. Demographics varied between the clinical success and non-success groups, including age, race, and region of facility. A current diagnosis of chronic respiratory disease (46% vs 42%) and diagnosis of pneumonia in the year prior to the MRSA pneumonia admission (37% vs 32%) were both more common in the clinical success group. Despite these significant differences, only two predictors of clinical success were identified in our study: previous complication of an implant or graft, including mechanical complications and infections, in the year prior to the MRSA pneumonia admission (OR, 1.55; 95% CI, 1.17–2.06) and treatment with linezolid (1.53; 1.12–2.10). Predictors of non-success included concomitant urinary tract infection diagnosis (OR, 0.82; 95% CI, 0.70–0.96), intravenous line (0.76; 0.66–0.89), previous coagulopathy (0.74; 0.56–0.96), previous amputation procedure (0.72; 0.53–0.98), current coagulopathy diagnosis (0.71; 0.53–0.96), dialysis (0.54; 0.38–0.76), multiple inpatient procedures (0.53; 0.45–0.62), inpatient surgery (0.48; 0.41–0.57), and previous endocarditis (0.24; 0.07–0.81). Discussion: MRSA pneumonia tends to affect complex patients, and identification of the predictors of clinical success is useful when considering different therapeutic approaches. Conclusions: In a national cohort of VA patients with MRSA pneumonia, treatment was the only modifiable variable predicting clinical success

Bacteremia is an independent risk factor for mortality in nosocomial pneumonia: a prospective and observational multicenter study

Introduction: Since positive blood cultures are uncommon in patients with nosocomial pneumonia (NP), the responsible pathogens are usually isolated from respiratory samples. Studies on bacteremia associated with hospital-acquired pneumonia (HAP) have reported fatality rates of up to 50%. The purpose of the study is to compare risk factors, pathogens and outcomes between bacteremic nosocomial pneumonia (B-NP) and nonbacteremic nosocomial pneumonia (NB-NP) episodes. Methods: This is a prospective, observational and multicenter study (27 intensive care units in nine European countries). Consecutive patients requiring invasive mechanical ventilation for an admission diagnosis of pneumonia or on mechanical ventilation for > 48 hours irrespective of admission diagnosis were recruited. Results: A total of 2,436 patients were evaluated; 689 intubated patients presented with NP, 224 of them developed HAP and 465 developed ventilation-acquired pneumonia. Blood samples were extracted in 479 (69.5%) patients, 70 (14.6%) being positive. B-NP patients had higher Simplified Acute Physiology Score (SAPS) II score (51.5 ± 19.8 vs. 46.6 ± 17.5, P = 0.03) and were more frequently medical patients (77.1% vs. 60.4%, P = 0.01). Mortality in the intensive care unit was higher in B-NP patients compared with NB-NP patients (57.1% vs. 33%, P < 0.001). B-NP patients had a more prolonged mean intensive care unit length of stay after pneumonia onset than NB-NP patients (28.5 ± 30.6 vs. 20.5 ± 17.1 days, P = 0.03). Logistic regression analysis confirmed that medical patients (odds ratio (OR) = 5.72, 95% confidence interval (CI) = 1.93 to 16.99, P = 0.002), methicillin-resistant Staphylococcus aureus (MRSA) etiology (OR = 3.42, 95% CI = 1.57 to 5.81, P = 0.01), Acinetobacter baumannii etiology (OR = 4.78, 95% CI = 2.46 to 9.29, P < 0.001) and days of mechanical ventilation (OR = 1.02, 95% CI = 1.01 to 1.03, P < 0.001) were independently associated with B-NP episodes. Bacteremia (OR = 2.01, 95% CI = 1.22 to 3.55, P = 0.008), diagnostic category (medical patients (OR = 3.71, 95% CI = 2.01 to 6.95, P = 0.02) and surgical patients (OR = 2.32, 95% CI = 1.10 to 4.97, P = 0.03)) and higher SAPS II score (OR = 1.02, 95% CI = 1.01 to 1.03, P = 0.008) were independent risk factors for mortality. Conclusions: B-NP episodes are more frequent in patients with medical admission, MRSA and A. baumannii etiology and prolonged mechanical ventilation, and are independently associated with higher mortality rates

A Comparison of Clinical Features and Mortality among Methicillin-Resistant and Methicillin-Sensitive Strains of Staphylococcus aureus Endocarditis

Our objective was to assess the clinical factors that would reliably distinguish methicillin-resistant S. aureus (MRSA) from methicillin-susceptible S. aureus (MSSA) endocarditis. A retrospective cohort study of clinical features and mortality in patients with MRSA and MSSA endocarditis between March 1986 and March 2004 was performed in a 750-bed, tertiary care teaching hospital. A total of 32 patients (10 MRSA [31.3%] vs 22 MSSA [68.7%]) were evaluated. Their mean age and sex ratio (male/female) were as follows: 30.8 ± 16.0 vs 24.4±19.6 years old and 6/4 vs 13/9, for MRSA and MSSA infective endocarditis (IE), respectively. Univariate and multivariate analyses revealed that persistent bacteremia was significantly more prevalent in MRSA IE (OR, 10.0 [1.480-67.552]; p, 0.018). There was a higher mortality trend for MRSA IE (50.0%) than for MSSA IE (9.1%) (p=0.019). However, persistent bacteremia was not associated with higher mortality (p>0.05). These results indicate that if persistent bacteremia is documented, the likelihood of MRSA endocarditis should be viewed as high, and the patient's antistaphylococcal therapy should be prolonged and/or changed to a more "potent" regimen

Predicting Risk for Death from MRSA Bacteremia1

Methicillin-resistant Staphylococcus aureus (MRSA) in the bloodstream is often fatal. Vancomycin is the most frequently prescribed drug for treatment of MRSA infections with demonstrated efficacy. Recently, however, some MRSA infections have not been responding to vancomycin, even those caused by strains considered susceptible. To provide optimal treatment and avoid vancomycin resistance, therapy should be tailored, especially for patients at highest risk for death. But who are these patients? A study that looked back at medical records and 699 frozen isolates found that risk for death from MRSA infection was highest among certain populations, including the elderly, nursing home residents, patients with severe sepsis, and patients with liver or kidney disease. Risk for death was not affected by the type of MRSA strain (vancomycin susceptible, heteroresistant, or intermediate resistant). Risk was lower among those who had consulted an infectious disease specialist. Thus, when choosing treatment for patients with MRSA infection, it is crucial to look at patient risk factors, not just MRSA strain type. For those at high risk, consultation with an infectious disease specialist is recommended

Patient-associated risk factors for acquisition of methicillin resistant Staphylococcus aureus(MRSA) in a tertiary hospital setting

MRSA is a dominant hospital pathogen because of its increasing incidence, the cost of treatment, antibiotic resistance, limited antimicrobial armamentarium, and associated increased mortality. Determining risk factors for MRSA acquisition in hospital settings has important public health relevance for defining targets for infection control, reduction in mortality from hospital-acquired infections, and decreasing hospitalization costs. A retrospective matched case-control study was initiated to determine patient-associated risk factors for MRSA acquisition at the Presbyterian University Hospital. It was hypothesized that risk factors for MRSA acquisition could be identified and used to enhance or tailor infection control strategies. Cases and two matched controls were selected among patients admitted to high risk units where MRSA screening was routinely done from January 2001 to December 2008. Cases were subjects who acquired MRSA during hospitalization. Variables collected were potential patient-associated risk factors associated with MRSA acquisition among cases versus controls. The odds of exposure to potential risk factors for MRSA acquisition were compared between cases and controls, using matched univariate conditional logistic regression. A single multivariate conditional logistic regression model identifying patient-specific risk factors significantly associated with MRSA acquisition was generated. The final model included 15 independently significant variables. Seven factors were positively associated with MRSA acquisition: primary diagnosis of respiratory disease, digestive tract disease, or injury/trauma, any diagnosis of pneumonia, cerebrovascular/peripheral vascular disease, intracranial ventricular shunt procedure, and a high risk unit stay prior to index culture. Eight variables were protective and included two beta lactam antibiotic classes (penicillin and cephalosporin), rifamycin, daptomycin/linezolid, proton pump inhibitors, history of transplant, extracorporeal membrane oxygenation, and intravascular stenting/catheterization. As 3 of the 7 factors positively associated with MRSA acquisition were conditions present on admission, they were not modifiable. Of the remaining 4, pneumonia could potentially be reduced by maintaining high compliance with pneumococcal vaccine. Admission to a high risk unit in itself is not modifiable. Although ventricular shunting was a factor, the lack of association with many common bedside or interventional procedures performed in these high risk areas argues for intensified environmental control and strict sterile technique for all procedures performed on patients

Association of Electronic Health Records with Methicillin-Resistant Staphylococcus aureus Infection in a National Sample

This study examined the relationship between advanced electronic health record (EHR) use in hospitals and rates of Methicillin-resistant Staphylococcus aureus (MRSA) infection in an inpatient setting. National Inpatient Sample (NIS) and Health Information Management Systems Society (HIMSS) Annual Survey are combined in the retrospective, cross-sectional analysis. A twenty percent simple random sample of the combined 2009 NIS and HIMSS datasets included a total of 1,032,905 patient cases of MRSA in 550 hospitals. Results of the propensity-adjusted logistic regression model revealed a statistically significant association between advanced EHR and MRSA, with patient cases from an advanced EHR being less likely to report a MRSA diagnosis code

Assessment of risk factors related to healthcare-associated methicillin-resistant Staphylococcus aureus infection at patient admission to an intensive care unit in Japan

<p>Abstract</p> <p>Background</p> <p>Healthcare-associated methicillin-resistant <it>Staphylococcus aureus </it>(HA-MRSA) infection in intensive care unit (ICU) patients prolongs ICU stay and causes high mortality. Predicting HA-MRSA infection on admission can strengthen precautions against MRSA transmission. This study aimed to clarify the risk factors for HA-MRSA infection in an ICU from data obtained within 24 hours of patient ICU admission.</p> <p>Methods</p> <p>We prospectively studied HA-MRSA infection in 474 consecutive patients admitted for more than 2 days to our medical, surgical, and trauma ICU in a tertiary referral hospital in Japan. Data obtained from patients within 24 hours of ICU admission on 11 prognostic variables possibly related to outcome were evaluated to predict infection risk in the early phase of ICU stay. Stepwise multivariate logistic regression analysis was used to identify independent risk factors for HA-MRSA infection.</p> <p>Results</p> <p>Thirty patients (6.3%) had MRSA infection, and 444 patients (93.7%) were infection-free. Intubation, existence of open wound, treatment with antibiotics, and steroid administration, all occurring within 24 hours of ICU admission, were detected as independent prognostic indicators. Patients with intubation or open wound comprised 96.7% of MRSA-infected patients but only 57.4% of all patients admitted.</p> <p>Conclusions</p> <p>Four prognostic variables were found to be risk factors for HA-MRSA infection in ICU: intubation, open wound, treatment with antibiotics, and steroid administration, all occurring within 24 hours of ICU admission. Preemptive infection control in patients with these risk factors might effectively decrease HA-MRSA infection.</p

Factors Predicting and Reducing Mortality in Patients with Invasive Staphylococcus aureus Disease in a Developing Country

BACKGROUND: Invasive Staphylococcus aureus infection is increasingly recognised as an important cause of serious sepsis across the developing world, with mortality rates higher than those in the developed world. The factors determining mortality in developing countries have not been identified. METHODS: A prospective, observational study of invasive S. aureus disease was conducted at a provincial hospital in northeast Thailand over a 1-year period. All-cause and S. aureus-attributable mortality rates were determined, and the relationship was assessed between death and patient characteristics, clinical presentations, antibiotic therapy and resistance, drainage of pus and carriage of genes encoding Panton-Valentine Leukocidin (PVL). PRINCIPAL FINDINGS: A total of 270 patients with invasive S. aureus infection were recruited. The range of clinical manifestations was broad and comparable to that described in developed countries. All-cause and S. aureus-attributable mortality rates were 26% and 20%, respectively. Early antibiotic therapy and drainage of pus were associated with a survival advantage (both p&lt;0.001) on univariate analysis. Patients infected by a PVL gene-positive isolate (122/248 tested, 49%) had a strong survival advantage compared with patients infected by a PVL gene-negative isolate (all-cause mortality 11% versus 39% respectively, p&lt;0.001). Multiple logistic regression analysis using all variables significant on univariate analysis revealed that age, underlying cardiac disease and respiratory infection were risk factors for all-cause and S. aureus-attributable mortality, while one or more abscesses as the presenting clinical feature and procedures for infectious source control were associated with survival. CONCLUSIONS: Drainage of pus and timely antibiotic therapy are key to the successful management of S. aureus infection in the developing world. Defining the presence of genes encoding PVL provides no practical bedside information and draws attention away from identifying verified clinical risk factors and those interventions that save lives

Adequacy of Antimicrobial Treatment and Outcome of Staphylococcus aureus Bacteremia in 9 Western European Countries

Background.Little is known about the incidence of inadequate treatment of severe Staphylococcus aureus infection in Europe. We aimed to evaluate the adequacy of antibiotic therapy for S. aureus bacteremia (SAB), to identify determinants of inadequate treatment, and to determine the effect of inadequate treatment on patient outcome in a representative selection of hospitals in 9 Western European countries. Methods.In this retrospective cohort study, all adult patients with SAB (due to methicillin-susceptible S. aureus [MSSA] or methicillin-resistant S. aureus [MRSA]) who were admitted to 60 randomly selected hospitals from 1 November 2007 through 31 December 2007 were included. Adequate antimicrobial therapy was defined as intravenous administration of at least 1 antibiotic to which the isolate showed in vitro susceptibility that was initiated within 2 days after onset of SAB. Results.A total of 334 SAB episodes (257 due to MSSA and 77 due to MRSA) were included. Ninety-four patients (28%) received inadequate empirical therapy (21% in the MSSA group and 52% in the MRSA group). Both length of stay before SAB onset and methicillin-resistant infection were associated with inadequate therapy, with adjusted odds ratios (ORs) of 1.01 (95% confidence interval [CI], 1.00-1.03) and 3.7 (95% CI, 2.2-6.4), respectively. Age (OR, 1.06; 95% CI, 1.03-1.10), Charlson comorbidity score (OR, 2.1; 95% CI, 1.2-3.6), severe sepsis or septic shock (OR, 2.7; 95% CI, 1.5-4.8), and intensive care unit stay at onset of SAB (OR, 2.9; 95% CI, 1.5-5.6) but not inadequate treatment (OR, 0.7; 95% CI, 0.4-1.3) were associated with increased 30-day mortality. Conclusion.Inadequate empirical antimicrobial therapy for SAB is common in Western Europe and is strongly associated with infection caused by MRSA. In this study, inadequate treatment was not associated with increased 30-day mortality rate