Risk factors for meticillin resistance and outcome of Staphylococcus aureus bloodstream infection in a Belgian university hospital

Sulforaphane and Its Bifunctional Analogs: Synthesis and Biological Activity

For decades, various plants have been studied as sources of biologically active compounds. Compounds with anticancer and antimicrobial properties are the most frequently desired. Cruciferous plants, including Brussels sprouts, broccoli, and wasabi, have a special role in the research studies. Studies have shown that consumption of these plants reduce the risk of lung, breast, and prostate cancers. The high chemopreventive and anticancer potential of cruciferous plants results from the presence of a large amount of glucosinolates, which, under the influence of myrosinase, undergo an enzymatic transformation to biologically active isothiocyanates (ITCs). Natural isothiocyanates, such as benzyl isothiocyanate, phenethyl isothiocyanate, or the best-tested sulforaphane, possess anticancer activity at all stages of the carcinogenesis process, show antibacterial activity, and are used in organic synthesis. Methods of synthesis of sulforaphane, as well as its natural or synthetic bifunctional analogues with sulfinyl, sulfanyl, sulfonyl, phosphonate, phosphinate, phosphine oxide, carbonyl, ester, carboxamide, ether, or additional isothiocyanate functional groups, and with the unbranched alkyl chain containing 2-6 carbon atoms, are discussed in this review. The biological activity of these compounds are also reported. In the first section, glucosinolates, isothiocyanates, and mercapturic acids (their metabolites) are briefly characterized. Additionally, the most studied anticancer and antibacterial mechanisms of ITC actions are discussed.

Type 2 diabetes mellitus and antibiotic-resistant infections: a systematic review and meta-analysis

BACKGROUND

Type 2 diabetes mellitus (T2DM) has been associated with infectious diseases; however, whether T2DM is associated with bacterial-resistant infections has not been thoroughly studied. We ascertained whether people with T2DM were more likely to experience resistant infections in comparison to T2DM-free individuals.

METHODS

Systematic review and random-effects meta-analysis. The search was conducted in Medline, Embase and Global Health. We selected observational studies in which the outcome was resistant infections (any site), and the exposure was T2DM. We studied adult subjects who could have been selected from population-based or hospital-based studies. I² was the metric of heterogeneity. We used the Newcastle-Ottawa risk of bias scale.

RESULTS

The search retrieved 3370 reports, 97 were studied in detail and 61 (449 247 subjects) were selected. Studies were mostly cross-sectional or case-control; several infection sites were studied, but mostly urinary tract and respiratory infections. The random-effects meta-analysis revealed that people with T2DM were twofold more likely to have urinary tract (OR=2.42; 95% CI 1.83 to 3.20; I² 19.1%) or respiratory (OR=2.35; 95% CI 1.49 to 3.69; I² 58.1%) resistant infections. Although evidence for other infection sites was heterogeneous, they consistently suggested that T2DM was associated with resistant infections.

CONCLUSIONS

Compelling evidence suggests that people with T2DM are more likely to experience antibiotic-resistant urinary tract and respiratory infections. The evidence for other infection sites was less conclusive but pointed to the same overall conclusion. These results could guide empirical treatment for patients with T2DM and infections.

Effects of the proportion of high-risk patients and control strategies on the prevalence of methicillin-resistant Staphylococcus aureus in an intensive care unit

Background

The presence of nosocomial pathogens in many intensive care units poses a threat to patients and public health worldwide. Methicillin-resistant Staphylococcus aureus (MRSA) is an important pathogen endemic in many hospital settings. Patients who are colonized with MRSA may develop an infection that can complicate their prior illness.

Methods

A mathematical model to describe transmission dynamics of MRSA among high-risk and low-risk patients in an intensive care unit (ICU) via hands of health care workers is developed. We aim to explore the effects of the proportion of high-risk patients, the admission proportions of colonized and infected patients, the probability of developing an MRSA infection, and control strategies on MRSA prevalence among patients.

Results

The increasing proportion of colonized and infected patients at admission, along with the higher proportion of high-risk patients in an ICU, may significantly increase MRSA prevalence. In addition, the prevalence becomes higher if patients in the high-risk group are more likely to develop an MRSA infection. Our results also suggest that additional infection prevention and control measures targeting high-risk patients may considerably help reduce MRSA prevalence as compared to those targeting low-risk patients.

Conclusions

The proportion of high-risk patients and the proportion of colonized and infected patients in the high-risk group at admission may play an important role on MRSA prevalence. Control strategies targeting high-risk patients may help reduce MRSA prevalence.

Reevaluation of the impact of methicillin-resistance on outcomes in patients with Staphylococcus aureus bacteremia and endocarditis

BACKGROUND/AIMS

Methicillin-resistant Staphylococcus aureus (MRSA) is highly prevalent in hospitals, and has recently emerged in the community. The impact of methicillin-resistance on mortality and medical costs for patients with S. aureus bacteremia (SAB) requires reevaluation.

METHODS

We searched studies with SAB or endocarditis using electronic databases including Ovid-Medline, Embase-Medline, and Cochrane Library, as well as five local databases for published studies during the period January 2000 to September 2011.

RESULTS

A total of 2,841 studies were identified, 62 of which involved 17,563 adult subjects and were selected as eligible. A significant increase in overall mortality associated with MRSA, compared to that with methicillin-susceptible S. aureus (MSSA), was evidenced by an odds ratio (OR) of 1.95 (95% confidence interval [CI], 1.73 to 2.21; p < 0.01). In 13 endocarditis studies, MRSA increased the risk of mortality, with an OR of 2.65 (95% CI, 1.46 to 4.80). When three studies, which compared mortality rates between CA-MRSA and CA-MSSA, were combined, the risk of methicillin-resistance increased 3.23-fold compared to MSSA (95% CI, 1.25 to 8.34). The length of hospital stay in the MRSA group was 10 days longer than that in the MSSA group (95% CI, 3.36 to 16.70). Of six studies that reported medical costs, two were included in the analysis, which estimated medical costs to be $9,954.58 (95% CI, 8,951.99 to 10,957.17).

CONCLUSION

MRSA is still associated with increased mortality, longer hospital stays and medical costs, compared with MSSA in SAB in studies published since the year 2000.

Isothiocyanates: An Overview of Their Antimicrobial Activity against Human Infections

The use of plant-derived products as antimicrobial agents has been investigated in depth. Isothiocyanates (ITCs) are bioactive products resulting from enzymatic hydrolysis of glucosinolates (GLs), the most abundant secondary metabolites in the botanical order Brassicales. Although the antimicrobial activity of ITCs against foodborne and plant pathogens has been well documented, little is known about their antimicrobial properties against human pathogens. This review collects studies that focus on this topic. Particular focus will be put on ITCs’ antimicrobial properties and their mechanism of action against human pathogens for which the current therapeutic solutions are deficient and therefore of prime importance for public health. Our purpose was the evaluation of the potential use of ITCs to replace or support the common antibiotics. Even though ITCs appear to be effective against the most important human pathogens, including bacteria with resistant phenotypes, the majority of the studies did not show comparable results and thus it is very difficult to compare the antimicrobial activity of the different ITCs. For this reason, a standard method should be used and further studies are needed.

The associations between socioeconomic status and risk of Staphylococcus aureus bacteremia and subsequent endocarditis - a Danish nationwide cohort study

BACKGROUND

Staphylococcus aureus bacteremia (SAB) is the leading cause of infective endocarditis in several countries. Since socioeconomic status (SES) is known to influence the risk of infectious diseases in general, we aimed to investigate the association between SES and SAB, and risk of subsequent endocarditis in a nationwide adult population.

METHODS

All Danish residents were consecutively included at age ≥ 30 years during 1996-2010. We obtained information on SES (highest attained educational level), comorbidities, and microbiologically verified SAB by cross-linking nationwide registries. The incidence rate ratios (IRRs) of SAB and later endocarditis were investigated using Poisson regression models adjusted for sex, age and year (reference = highest SES).

RESULTS

Our study population comprised 3,394,936 individuals (median age = 43.2 years). Over a median follow-up of 15.9 years, 13,181 individuals acquired SAB. SES was inversely associated with SAB acquisition, which declined with increasing age, e.g. in individuals with lowest SES, IRRs were 3.78 (95% confidence interval [CI] = 2.89-4.95) in age 30-50 years, 1.87 (CI = 1.60-2.18) in age > 50-70 years and 1.31 (CI = 1.11-1.54) in age > 70 years (interaction-p < 0.0001). Adjustment for comorbidities attenuated the IRRs, but the pattern persisted. No association between SES and endocarditis risk among patients with SAB was observed.

CONCLUSIONS

Decreasing SES was associated with an increased risk of SAB, particularly in younger adults. SES was not associated with risk of subsequent endocarditis.

Epidemiology and molecular characteristics of methicillin-resistantStaphylococcus aureus from skin and soft tissue infections in Shiraz, Iran

BACKGROUND/AIM

Panton-Valentine leukocidin (PVL)-positive methicillin-resistant Staphylococcus aureus (MRSA) infections are increasing in some regions of Iran. The aim of the current study was to assess the epidemiology and molecular characteristics of S. aureus isolated from patients with skin infections in Shiraz, Iran.

MATERIALS AND METHODS

Swab samples were obtained from patients admitted to the skin and burn units of hospitals. The medical records of each patient were collected via questionnaire. All staphylococcal isolates were collected and examined by conventional methods for detecting S. aureus strains. PCR was used to detect S. aureus harboring the mecA and pvl genes.

RESULTS

Out of 243 staphylococcal isolates, 55 (22.6%) S. aureus and 91 (37.4%) S. epidermidis were detected. Of the 45 patients, 21 (46.7%) were S. aureus carriers. The mecA gene was identified in 60% of S. aureus isolates, and the rest were sensitive to methicillin. Of the S. aureus isolates, 54.5% were positive for the pvl gene.

CONCLUSION

This study revealed a high prevalence of PVL-positive MRSA strains in the evaluated hospitals. Thus, early diagnosis of infections caused by this pathogen seems to be necessary by intake screening allowing for proper treatment, especially in high-risk patients and in order to prevent the spread of infection.

Survival Benefit of Empirical Therapy for Staphylococcus aureus Bloodstream Infections in Infants

BACKGROUND

The impact of early adequate empirical antibiotic therapy on outcomes of infants in the neonatal intensive care unit (NICU) who develop Staphylococcus aureus bloodstream infections (BSI) is unknown.

METHODS

Infants with S. aureus BSI discharged in 1997-2012 from 348 NICUs managed by the Pediatrix Medical Group were identified. Early adequate empirical antibiotic therapy was defined as exposure to ≥1 antibiotic with anti-staphylococcal activity on the day the first positive blood culture was obtained. All other cases were defined as inadequate empirical antibiotic therapy. We evaluated the association between inadequate empirical antibiotic therapy on outcomes controlling for gestational age, small for gestational age status, gender, discharge year, mechanical ventilation, inotropic support and use of supplemental oxygen. The primary outcome was 30-day mortality. Secondary outcomes were 7-day mortality, death before hospital discharge and length of bacteremia.

RESULTS

Of the 3339 infants with S. aureus BSI, 2492 (75%) had methicillin-susceptible S. aureus (MSSA) BSI and 847 (25%) had methicillin-resistant S. aureus (MRSA) BSI. Inadequate empirical antibiotic therapy was administered in 725 (22%) cases. Inadequate empirical antibiotic therapy was associated with increased 30-day mortality (odds ratio: 2.03; 95% confidence interval: 1.08-3.82) among infants with MRSA BSI. Inadequate empirical antibiotic therapy was not associated with increases in mortality among infants with MSSA BSI.

CONCLUSIONS

After controlling for confounders, inadequate empirical antibiotic therapy was associated with a modestly increased mortality at 30 days for infants with MRSA BSI.

Antimicrobial activity of isothiocyanates from cruciferous plants against methicillin-resistant Staphylococcus aureus (MRSA)

Purified isothiocyanates from cruciferous plants (Brassicacea, Syn. Cruciferae) plants were evaluated against 15 isolates of methicillin-resistant S. aureus isolated from diabetic foot-ulcer patients aiming the study of the potential usage of allyl-isothiocyanate, benzyl-isothiocyanate and 2-phenylethyl-isothiocyanate against this important bacteria. Disc diffusion and minimum inhibitory concentration methods were used to access the antimicrobial activity. The index (Ia) and rate (Ra) of the antibacterial activity for each compound were calculated. The results showed a highly dose-dependent compound and chemical structure antibacterial effectiveness. The results showed a strong relation between the chemical structure of isothiocyanates and its antibacterial effectiveness. The benzyl-isothiocyanate was the most effective with a minimum inhibitory concentration varying between 2.9 and 110 µg· mL⁻¹ with an antibacterial activity rate up to 87%. Moreover, their antibacterial activity was mainly bactericidal. This study provides scientific evidence that isothiocyanates have an interesting biological value and must be considered as an important tool to be used against MRSA.

Risk factors for methicillin-resistant Staphylococcus aureus bacteraemia differ depending on the control group chosen

Methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia cause significant morbidity and mortality in hospitalized patients. Using a nested case-control design, 204 MRSA bacteraemia cases were compared to 301 unmatched methicillin-susceptible Staphylococcus aureus (MSSA) bacteraemia controls and were matched 1:2 with non-infected controls. The independent risk factors for MRSA bacteraemia compared to MSSA bacteraemia were older age (P = 0·048), major organ transplant during current hospital stay (P = 0·016) and quinolone use (P = 0·016). Cases were more likely than non-infected controls to have renal failure (P = 0·003), cirrhosis (P = 0·013), and a central venous catheter (P = 0·003) after controlling for other risk factors. This large case-control study made it possible to assess risk factors for MRSA bacteraemia using two sets of controls and showed that risk factors differed greatly depending on the control group chosen. These results confirm the need for careful selection of appropriate control groups and the need to carefully adjust for underlying severity of illness.

Thirty-day mortality in UK patients with community-onset and hospital-acquired meticillin-susceptible Staphylococcus aureus bacteraemia

BACKGROUND

The difference in mortality between patients with community-onset and hospital-acquired Staphylococcus aureus infections has rarely been described and where it has, results have been conflicting.

AIM

To determine 30-day mortality in consecutive patients with meticillin-susceptible Staphylococcus aureus (MSSA) bacteraemia and the association between community-onset infection and outcome.

METHODS

From August 2007 to July 2011, demographic, clinical and microbiological data were prospectively collected on patients with MSSA bacteraemia. Patients were followed until death, hospital discharge or recovery from infection. Multivariate logistic regression was used to determine the association between community-onset infection and 30-day mortality.

FINDINGS

A total of 403 bacteraemic episodes occurred in 392 patients. Overall, there were 44 deaths (11.2%; 95% confidence interval: 7.9-14.0%) at 7 days and 101 deaths (25.8%; 21.5-30.4%) at 30 days. The difference in 30-day mortality between patients with community-onset and hospital-acquired infection was 71/256 (27.7%) versus 31/147 21.1%). Community-onset infection more frequently caused infective endocarditis (13/14, 92.9%), vertebral osteomyelitis (12/13, 92.3%) and skin and soft tissue infection (61/71, 85.9%) whereas intravascular catheter-associated infections were predominantly hospital-acquired (60/82, 73.2%). Age, Pitt score, Charlson comorbidity index (CCI), specific sites of infection (skin and soft tissue, lower respiratory tract and peripheral joints) and delay in appropriate treatment were strongly associated with 30-day mortality. In multivariate analysis, after adjustment for age, CCI and delay in appropriate treatment, community-onset infection was strongly associated with 30-day mortality (odds ratio: 1.59; 95% confidence interval: 0.91-2.80).

CONCLUSIONS

Compared with hospital-acquired MSSA bacteraemic infection, community-onset infection was associated with worse 30-day outcomes. Hospital-acquired MSSA bacteraemic infections were rarely metastatic, frequently associated with medical devices and patients had better outcomes.

Methicillin-resistant Staphylococcus aureus bloodstream infection: risk factors and clinical outcome in non-intensive-care units

INTRODUCTION

Methicillin-resistant Staphylococcus aureus (MRSA) is spread out in hospitals across different regions of the world and is regarded as the major agent of nosocomial infections, causing infections such as skin and soft tissue pneumonia and sepsis. The aim of this study was to identify risk factors for methicillin-resistance in Staphylococcus aureus bloodstream infection (BSI) and the predictive factors for death.

METHODS

A retrospective cohort of fifty-one patients presenting bacteraemia due to S. aureus between September 2006 and September 2008 was analysed. Staphylococcu aureus samples were obtained from blood cultures performed by clinical hospital microbiology laboratory from the Uberlândia Federal University. Methicillinresistance was determined by growth on oxacillin screen agar and antimicrobial susceptibility by means of the disk diffusion method.

RESULTS

We found similar numbers of MRSA (56.8%) and methicillin-susceptible Staphylococcus aureus (MSSA) (43.2%) infections, and the overall hospital mortality ratio was 47%, predominantly in MRSA group (70.8% vs. 29.2%) (p=0.05). Age (p=0.02) was significantly higher in MRSA patients as also was the use of central venous catheter (p=0.02). The use of two or more antimicrobial agents (p=0.03) and the length of hospital stay prior to bacteraemia superior to seven days (p=0.006) were associated with mortality. High odds ratio value was observed in cardiopathy as comorbidity.

CONCLUSIONS

Despite several risk factors associated with MRSA and MSSA infection, the use of two or more antimicrobial agents was the unique independent variable associated with mortality.

Modeling methicillin-resistant Staphylococcus aureus in hospitals: transmission dynamics, antibiotic usage and its history

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) is endemic in many hospital settings, posing substantial threats and economic burdens worldwide.

METHODS

We propose mathematical models to investigate the transmission dynamics of MRSA and determine factors that influence the prevalence of MRSA infection when antibiotics are given to patients to treat or prevent infections with either MRSA itself or other bacterial pathogens.

RESULTS

Our results suggest that: (i) MRSA always persists in the hospital when colonized and infected patients are admitted; (ii) the longer the duration of treatment of infected patients and the lower the probability of successful treatment will increase the prevalence of MRSA infection; (iii) the longer the duration of contamination of health care workers (HCWs) and the more their contacts with patients may increase the prevalence of MRSA infection; (iv) possible ways to control the prevalence of MRSA infection include treating patients with antibiotic history as quickly and efficiently as possible, screening and isolating colonized and infected patients at admission, and compliance with strict hand-washing rules by HCWs.

CONCLUSION

Our modeling studies offer an approach to investigating MRSA infection in hospital settings and the impact of antibiotic history on the incidence of infection. Our findings suggest important influences on the prevalence of MRSA infection which may be useful in designing control policies.

Predictors of mortality in Staphylococcus aureus Bacteremia

Staphylococcus aureus bacteremia (SAB) is an important infection with an incidence rate ranging from 20 to 50 cases/100,000 population per year. Between 10% and 30% of these patients will die from SAB. Comparatively, this accounts for a greater number of deaths than for AIDS, tuberculosis, and viral hepatitis combined. Multiple factors influence outcomes for SAB patients. The most consistent predictor of mortality is age, with older patients being twice as likely to die. Except for the presence of comorbidities, the impacts of other host factors, including gender, ethnicity, socioeconomic status, and immune status, are unclear. Pathogen-host interactions, especially the presence of shock and the source of SAB, are strong predictors of outcomes. Although antibiotic resistance may be associated with increased mortality, questions remain as to whether this reflects pathogen-specific factors or poorer responses to antibiotic therapy, namely, vancomycin. Optimal management relies on starting appropriate antibiotics in a timely fashion, resulting in improved outcomes for certain patient subgroups. The roles of surgery and infectious disease consultations require further study. Although the rate of mortality from SAB is declining, it remains high. Future international collaborative studies are required to tease out the relative contributions of various factors to mortality, which would enable the optimization of SAB management and patient outcomes.

The impact of diabetes on the pathogenesis of sepsis

Diabetes is associated with an increased susceptibility to infection and sepsis. Conflicting data exist on whether the mortality of patients with sepsis is influenced by the presence of diabetes, fuelling the ongoing debate on the benefit of tight glucose regulation in patients with sepsis. The main reason for which diabetes predisposes to infection appears to be abnormalities of the host response, particularly in neutrophil chemotaxis, adhesion and intracellular killing, defects that have been attributed to the effect of hyperglycaemia. There is also evidence for defects in humoral immunity, and this may play a larger role than previously recognised. We review the literature on the immune response in diabetes and its potential contribution to the pathogenesis of sepsis. In addition, the effect of diabetes treatment on the immune response is discussed, with specific reference to insulin, metformin, sulphonylureas and thiazolidinediones.

Methicillin resistance of Staphylococcus species among health care and nonhealth care workers undergoing cataract surgery

Purpose:

The purpose of this study is to characterize the bacterial flora of the ocular and periocular surface in cataract surgery patients and to determine the prevalence of methicillin resistance among staphylococcal isolates obtained from health care workers (HCWs) and non-HCWs.

Methods:

In this prospective, multicenter, case series study, eyelid and conjunctival cultures were obtained from the nonoperative eye of 399 consecutive cataract patients on the day of surgery prior to application of topical anesthetics, antibiotics, or antiseptics. Speciation and susceptibility testing were performed at the Dean A. McGee Eye Institute. Logistic regression was utilized to evaluate whether any factors were significant in predicting the presence of methicillin-resistant staphylococcal isolates.

Results:

Staphylococcus epidermidis (62.9%), followed by S. aureus (14.0%), was the most frequently isolated organism. Methicillin-resistant S. epidermidis accounted for 47.1% (178/378) of S. epidermidis isolates, and methicillin-resistant S. aureus accounted for 29.5% (26/88) of S. aureus isolates. Methicillin-resistant staphylococcal isolates were found in 157 of 399 (39.3%) patients, the majority (89.2%) of whom were non-HCWs. The likelihood of being colonized with methicillin-resistant organisms increased with age (odds ratio [OR], 1.27; 95% confidence interval [CI]: 1.02–1.58; P = 0.04) but decreased with diabetes (OR, 0.51; 95% CI: 0.29–0.89; P = 0.02). Being a HCW (OR, 1.25; 95% CI: 0.61–2.58; P = 0.54) was not a risk factor for colonization with methicillin-resistant organisms.

Conclusion:

Patients without exposure to health care environments are as likely as HCWs to be colonized with methicillin-resistant organisms. Increasing methicillin resistance with age may partially explain the increased risk of endophthalmitis reported with older age.

Risk factors and mortality of nosocomial infections of methicillin-resistant Staphylococcus aureus in an intensive care unit

PURPOSE

Methicillin-resistant Staphylococcus aureus (MRSA) infections are an increasing worldwide problem. We determined risk factors and predictors of mortality of MRSA nosocomial infections (NIs).

MATERIALS AND METHODS

A prospective cohort study was performed in an adult mixed medical and surgical intensive care unit from 2003 to 2007. Stratified analyses and generalized linear modeling were used to assess risk factors and predictors of infection and mortality.

RESULTS

A total of 184 infections (3.6% of all infections) were due to S aureus, and 97.8% of these were methicillin resistant. The most common infection sites were respiratory tract (35.6%) and bloodstream (30.6%). Stratified analyses of length of stay (LOS) before onset of MRSA NI and death indicated that MRSA infection (odds ratio [OR], 38.49; 95% confidence interval [CI], 25.53-58.09) and mortality (OR, 4.72; 95% CI, 1.92-11.99) were more likely for LOS more than 15 days than for LOS less than 7 days. After controlling for potentially confounding factors by use of generalized linear modeling analysis, we identified the following as independent risk factors: LOS before onset of MRSA infection (OR, 1.03; 95% CI, 0.01-1.04), serum creatinine (OR, 5.87; 95% CI, 1.37-9.21) level, use of mechanical ventilator (OR, 6.71; 95% CI, 1.58-8.5), and central venous catheter (OR, 1.13; 95% CI, 1.05-1.31).

CONCLUSIONS

Methicillin resistance is very common with S aureus infection. In our intensive care unit, use of invasive devices/procedures and LOS were the most important risk factors for infection.

Rapid differentiation of methicillin-resistant Staphylococcus aureus and methicillin-susceptible Staphylococcus aureus from blood cultures by use of a direct cefoxitin disk diffusion test

A total of 276 blood culture bottles with Staphylococcus aureus were tested by direct cefoxitin disk diffusion testing; 105 (38.1%) had zone sizes of </=17 mm (all 105 had methicillin-resistant S. aureus [MRSA]), 18 (6.5%) had zone sizes that measured 18 mm (17 had MRSA and 1 had methicillin-susceptible S. aureus [MSSA]), 8 (2.9%) had zone sizes that measured 19 mm (6 had MRSA and 2 had MSSA), 8 (2.9%) had zone sizes that measured 20 mm (6 had MRSA and 2 had MSSA), and 137 (49.6%) had zone sizes of >/=21 mm (all 137 had MSSA). Detection of MRSA/MSSA in blood cultures could be reported 10 to 24 h earlier for 88% of cultures with total accuracy.