Management Of Methicillin-resistant Staphylococcus Aureus Research Articles

Evaluation of Antibacterial and Antibiofilm Activities of Fennel Seed Extract Against Methicillin-resistant Staphylococcus aureus

Background: Antimicrobial resistance against pathogenic bacterial strains is the current problem faced by the world. Medicinal plants are being focussed for new alternatives to routine antibiotics for novel therapeutic and antimicrobial approaches. Objective: In this present study, fennel extract from Foeniculum vulgare plant was investigated against methicillin-resistant Staphylococcus aureus (MRSA). Method: Ethanol extraction of fennel seeds was performed and minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and time-kill curve was studied to find antimicrobial activities. Biofilm eradication was estimated by crystal violet assay. Result: Antimicrobial study showed a MIC of 500 μg/ml and MBC of 1000 μg/ml for fennel extract. Sub-inhibitory concentrations (½ MIC and ¾ MIC) started to kill bacterial cells after the addition of fennel extract at mid-log phase of growth. Test phytochemical eradicated 38.7%, 62.2%, and 76.9% of MRSA biofilm from microtitre plate when added at a concentration of 250 μg/ml, 375 μg/ml and 500 μg/ml, respectively. Conclusion: This study showed different bactericidal and antibiofilm activity of fennel seed extract against MRSA. We suggested that the phytocompound could be a promising candidate and further investigation is needed to isolate the active component of the extract for the management of MRSA.

Exploring Treatment Options for Methicillin-Resistant Staphylococcus Aureus through a Mixed Methods Approach

Methicillin-resistant Staphylococcus aureus (MRSA) is a major public health concern, demanding multifaceted treatment strategies due to its complex nature. This study aimed to bridge the gap in understanding MRSA's clinical presentation, management, and outcomes by employing a mixed-methods approach. Through an extensive literature review and a singlecenter retrospective patient record review, the study offered insights into MRSA management, from diagnosis to treatment. The analysis included 44 patients, who presented to an outpatient dermatology practice. Results found a broad age range, revealing that 68.2% were treated with both topical and oral medications. Antibiotic susceptibility tests showed high resistance to Penicillin (84.1%) and high susceptibility to drugs like Linezolid (95.5%) and Moxifloxacin (97.7%). The literature review examined 22 relevant articles from the past decade. The study's findings emphasize the diversity of MRSA infections and the challenges in treatment, highlighting variations in antibiotic susceptibility and the urgent need for innovative approaches. It serves as a substantial contribution to the existing body of knowledge on MRSA and may inform future research and clinical practice.

Methicillin-Resistant Staphylococcus aurous: Epidemiology, Transmission and New Alternative Therapies: A Narrative Review.

Over the last decade, we were facing medical struggle by the emergence of multi-resistant bacteria, especially methicillin-resistant Staphylococcus aureus (MRSA). MRSA infections are still causing a growing global concern due to the rapid adaptive multidrug resistance to conventional antibiotics in human, community and veterinary medicine. Here we provide an overview about MRSA epidemiology, transmission and alternative potential treatments particularly new discovered phytochemicals with biological activity. In this narrative review, bibliographic data was collected from literature search databases: Google Scholar, web of science and PubMed/MEDLINE during recent years (2016 to 2021). MRSA is responsible of wide spectrum life threatening infections such us septicemia, endocarditis, and wound infections. It has epidemic potential in hospitals, that is responsible of most nosocomial infections leading to mortality and constitute a real burden for the healthcare systems. Effective preventive strategies for management of MRSA are highly required moreover, the identification and development of novel drugs or active biomolecules through phytochemicals are time challenging to face new resistant strains.

Prevalence of Methicillin-resistant Staphylococcus Aureus in India: A Systematic Review and Meta-analysis

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) has increased and become a serious concern worldwide, including India. Additionally, MRSA isolates are showing resistance to other chemotherapeutic agents. Isolated and valuable reports on the prevalence of MRSA are available in India. There is no systematic review on the prevalence of MRSA in one place; hence, this study was planned. The overall prevalence of MRSA in humans in India was evaluated state-wise, zone-wise, and year-wise. A systematic search from PubMed, Indian journals, Google Scholar, and J-Gate Plus was carried out and retrieved 98 eligible articles published from 2015 to 2020 in India. The statistical analysis of data was conducted using R software. The overall prevalence of MRSA was 37% (95% CI: 32–41) from 2015 to 2019. The pooled prevalence of MRSA zone-wise was 41% (95% CI: 33–50), 43% (95% CI: 20–68), 33% (95% CI: 24–43), 34% (95% CI: 26–42), 36% (95% CI: 25–47), and 40% (95% CI: 23–58) for north, east, west, south, central, and northeast region-zones, respectively. The state-wise stratified results showed a predominance of MRSA in Jammu and Kashmir with 55% (95% CI: 42–67) prevalence, and the lowest was 21% (95% CI: 11–34) in Maharashtra. The study indicated that the prevalence data would help in formulating and strict implementation of control measures in hospital areas to prevent the outbreak of MRSA infection and management of antibiotic usage.

Infection control measures in nosocomial MRSA outbreaks-Results of a systematic analysis.

There is a lack of data on factors that contribute to the implementation of hygiene measures during nosocomial outbreaks (NO) caused by Methicillin-resistant Staphylococcus aureus (MRSA). Therefore, we first conducted a systematic literature analysis to identify MRSA outbreak reports. The expenditure for infection control in each outbreak was then evaluated by a weighted cumulative hygiene score (WCHS). Effects of factors on this score were determined by multivariable linear regression analysis. 104 NO got included, mostly from neonatology (n = 32), surgery (n = 27), internal medicine and burn units (n = 10 each), including 4,361 patients (thereof 657 infections and 73 deaths) and 279 employees. The outbreak sources remained unknown in 10 NO and were not reported from further 61 NO. The national MRSA prevalence did not correlate with the WCHS (p = .714). There were significant WCHS differences for internal medicine (p = 0.014), burn units (p<0.01), for Japanese NO (p<0.01), and NO with an unknown source (p<0.01). In sum, management of a NO due to MRSA does not depend on the local MRSA burden. However, differences of MRSA management among medical departments do exist. Strict adherence to the Outbreak Reports and Intervention Studies Of Nosocomial infection (ORION) statement is highly recommended for. The WCHS may also serve as a useful tool to quantify infection control effort and could therefore be used for further investigations.

Management of acute bacterial skin and skin structure infections in India: are we equipped to meet the challenges of the growing menace of methicillin-resistant Staphylococcus aureus?

Staphylococcus aureus (S. aureus) is a Gram-positive facultative anaerobic bacterium that colonizes the skin and nasal passages of humans. The incidence of invasive S. aureus infections has increased over the past decades and is associated with poor outcomes and high mortality rates. S. aureus is responsible for almost one-third of acute bacterial skin and skin structure infections with methicillin-resistant Staphylococcus aureus (MRSA) accounting for a large proportion of these. The S. aureus strains prevalent inIndia are more aggressive and there are recent reports of the emergence of the more virulent multidrug resistant lineages ST2371 and ST8. Management of these infections is complicated by the fact that antimicrobial stewardship is non-existent, the choice of treatment is often empirical and available treatment options are limited due to a high prevalence of resistance strains. Currently available anti-MRSA agents include vancomycin, teicoplanin, linezolid, daptomycin, tigecycline, and clindamycin. However, the emergence of resistant strains and several undesirable features related to the safety and tolerability of these agents have limited the options available for the management of MRSA infections. A newer, safe and efficacious antibiotic is thus an unmet need for the management of MRSA in patients with acute bacterial skin and skin structure infections. In this review we explore the current and future trends in the management of acute bacterial skin and skin structure infections highlighting the challenges in their management in India, and current progress in the development of some novel drugs for the management of MRSA infections.

Stopping the routine use of contact precautions for management of MRSA and VRE at three academic medical centers: An interrupted time series analysis

Contact precautions (CP) are a widely adopted strategy to prevent cross-transmission of organisms, commonly methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE). Some hospitals have discontinued CP for patients with MRSA or VRE; however, the impact on hospital-acquired infection rates (HAI) has not been assessed systematically. Retrospective multicenter interrupted time series between 2002 and 2017 at three academic hospitals. Participating hospitals discontinued CP for patients with contained body fluids who were colonized or infected with MRSA or VRE. The primary intervention was stopping the use of CP. Secondary interventions were horizontal infection prevention strategies. The primary outcomes were rates of central line-associated bloodstream infections, catheter-associated urinary tract infections, mediastinal surgical site infection, and ventilator-associated pneumonia due to MRSA, VRE, or any organism using Centers for Disease Control and Prevention National Healthcare Safety Network surveillance definitions. Central line-associated bloodstream infections, catheter-associated urinary tract infections, mediastinal surgical site infection, and ventilator-associated pneumonia rates trended down at each institution. There were no statistically significant increases in these infections associated with discontinuing CP. Individual horizontal infection prevention strategies variably impacted HAI outcomes. Stopping the routine use of CP for patients with contained body fluids who are colonized or infected with MRSA or VRE did not result in increased HAIs. Bundled horizontal infection prevention strategies resulted in sustained HAI reductions.

Antibacterial, anti-biofilm activity and mechanism of action of pancreatin doped zinc oxide nanoparticles against methicillin resistant Staphylococcus aureus

Staphylococcus aureus are known to cause diseases from normal skin wound to life intimidating infections. Among the drug resistant strain, management of methicillin resistant Staphylococcus aureus (MRSA) is very difficult by using conventional antibiotic treatment. Both Zinc oxide nanoparticles (ZnONPs) and pancreatin (PK) are known to have antibacterial activity. Our main objective is to dope PK on ZnONPs to reduced zinc-oxide toxicity but increased anti-bacterial and anti-biofilms activity. In present study, we showed that, functions of zinc oxide nanoparticles with pancreatin enzyme (ZnONPs-PK) have anti-bacterial, anti-biofilms, anti-motility and anti-virulence properties against MRSA. Moreover, ZnONPs-PK were more potent to eradicate MRSA than only ZnONPs and PK. Application of the produced nano-composites as treatment on infected swine dermis predominantly reflects the potential treatment property of it. The vancomycin sensitivity of MRSA was significantly increased on application with ZnONPs-PK. Further study revealed cell membrane was the target of the ZnONPs-PK and that leads to oxidative damage of the cells. The produced nanoparticles were found completely non-toxic to human’s keratinocytes and lung epithelial cell lines at its bactericidal concentration. Overall, this study emphasizes the potential mechanisms underlying the selective bactericidal properties of ZnONPs-PK against MRSA. This novel nanoparticle strategy may provide the ideal solution for comprehensive management of MRSA and its associated diseases with minimising the use of antibiotics.

In vitro antibacterial activity of medicinal plants against biofilm-forming methicillin-resistant Staphylococcus aureus: efficacy of Moringa stenopetala and Rosmarinus officinalis extracts

The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) is slowly rising in Ethiopia for the past few decades. Therefore, novel classes of antibiotics are indispensable to combat the increased incidence of newly emerging multidrug-resistant bacteria like MRSA. Terrestrial flora is considered as a reservoir of novel bioactive secondary metabolites as they have provided us with the largest array of natural products. In this background, the present study is intended to evaluate the in-vitro antibacterial efficacy of five medicinal plants (Ocimum lamiifolium Hochst. ex Benth., Rosmarinus officinalis L, Catharanthus roseus Linn., Azadirachta indica A. Juss and Moringa stenopetala Bac) against a panel of seven biofilm-forming MRSA. The leaves of the plants were extracted in organic solvents of varying polarity and the resultant crude extracts of respective medicinal plants were inspected for their antimicrobial activity by well diffusion technique. Minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) of the plant extracts against MRSA were determined by the broth dilution method. Besides, an anti-biofilm assay of the most potent plant extract was also performed, after which its chemical constituents were delineated by combined Gas Chromatographic and Mass Spectroscopic profiling (GC-MS). The results revealed that, of the five plants, three species including M. stenopetala, R. officinalis, and O. lamifolium exhibited significant antibacterial activity. Organic solvents with high and medium polarity were excellent in extracting antimicrobials compared to nonpolar solvents. The broadest and highest rank of activity was observed in the crude ethanolic extract of M. stenopetala. Based on the MIC/MBC ratio, the crude ethanolic extract of M. stenopetala was determined to be bacteriostatic. Anti-biofilm assay showed that the extract of M. stenopetala fairly inhibited the growth of MRSA in the preformed biofilm matrix. The GC-MS analysis of M. stenopetala revealed the presence of twelve compounds with antimicrobial activity. The present study provides new insight into the development of novel drug leads to the management of MRSA.

In Vitro Synergistic Effect of Vancomycin and Some Antibacterial Agents Against Clinical Methicillin-Resistant and Sensitive Staphylococcus aureus Isolates.

Methicillin-resistant Staphylococcus aureus (MRSA) can be responsible for serious long-term infections. Sometimes monotherapy can be ineffective for the treatment of these infections; hence, it is hypothesized that combined drug treatment can be more potent in these cases. The aim of this study was to investigate the synergistic effect of vancomycin and eight other antibacterial agents to identify the best combination pattern in the management of MRSA. Ameri-Ziaee double synergism test (AZDAST), double-disc, checkerboard, and time-kill methods were used to assess the synergistic effect in 24 isolates of S. aureus, including 22 MRSA and two methicillin-sensitive S. aureus (MSSA). Furthermore, based on the results, handmade combined antibiotic discs were prepared to evaluate the results of the checkerboard and time-kill methods at the plate level. All the isolates were sensitive to vancomycin, linezolid, and daptomycin. Furthermore, penicillin had the highest resistance (100%) in all isolates. The synergistic activities were observed, when the vancomycin was combined with the imipenem, using three double-disc, checkerboard, and time-kill methods. The sub-minimum inhibitory concentration (MIC) amount of the combined discs could increase the diameter of the inhibition zone, confirming the results. The data obtained from this study suggested that vancomycin and imipenem together, even at sub-MIC, could be effective against MRSA and MSSA infections.

Methicillin-resistant Staphylococcus aureus in Intensive Care Unit Setting of India: A Review of Clinical Burden, Patterns of Prevalence, Preventive Measures, and Future Strategies.

ABSTRACTAimThe aim of this review article is not only to analyze the clinical burden of methicillin-resistant Staphylococcus aureus (MRSA) in intensive care unit (ICU) setting of India, along with the patterns of prevalence and its prevention measures, but also to focus on the new anti-MRSA research molecules which are in late stage of clinical development.BackgroundMethicillin resistance is reported to be present in 13–47% of Staphylococcus aureus infections in India. Therapeutic options to combat MRSA are becoming less, because of emerging resistance to multiple classes of antibiotics. Intensive care units are the harbinger of multidrug-resistant organisms including MRSA and are responsible for its spread within the hospital. The emergence of MRSA in ICUs is associated with poor clinical outcomes, high morbidity, mortality, and escalating treatment costs. There is an urgency to bolster the antibiotic pipeline targeting MRSA. The research efforts for antibiotic development need to match with the pace of emergence of resistance, and new antibiotics are needed to control the impending threat of untreatable MRSA infections.Review resultsFortunately, several potential antibiotic agents are in the pipeline and the future of MRSA management appears reassuring.Clinical significanceThe authors believe that this knowledge may help form the basis for strategic allocation of current healthcare resources and the future needs.How to cite this articleMehta Y, Hegde A, Pande R, Zirpe KG, Gupta V, Ahdal J, et al. Methicillin-resistant Staphylococcus aureus in Intensive Care Unit Setting of India: A Review of Clinical Burden, Patterns of Prevalence, Preventive Measures, and Future Strategies. Indian J Crit Care Med 2020;24(1):55–62.

Surveillance and Isolation of Methicillin-Resistant Staphylococcus aureus Colonization in the Neonatal Intensive Care Unit.

Neonatal sepsis causes 1.4 million (36%) neonatal deaths annually. Staphylococcus aureus (SA), a common skin pathogen, remains the second leading cause of late-onset sepsis in the neonatal intensive care unit (NICU). Methicillin-resistant Staphylococcus aureus (MRSA), a resistant strain of SA, has created a significant global communicable health risk, especially in the NICU. To examine evidence related to NICU infection control practices surrounding MRSA surveillance, identification, and isolation in response to the clinical question, "What strategies should be universally implemented in the NICU to identify and prevent the spread of MRSA?" Databases were examined for articles on the topical area of MRSA in the neonate. Key terms were used to streamline the search, resulting in 20 primary works and 3 guideline/consensus statements considered imperative in response to the clinical questions. Hand hygiene remains the cornerstone to sound infection control practice. Colonization often leads to systemic infection, with smaller neonates at greatest risk. Hospital infection control compliance has improved outcomes. MRSA surveillance has reduced horizontal spread. No universal, specific recommendations exist to guide surveillance and management of MRSA in the NICU. Standardized guidelines with procedures for hand hygiene, patient surveillance and isolation, and patient cohorting with recommended staffing patterns should guide practice in the NICU. Both MRSA culture and polymerase chain reaction effectively identify positive patients. Decolonization practices are not yet clear. Evaluation of standard isolation practices versus outbreak response and approaches to neonatal decolonization should be evaluated for efficacy, safety, and resistance.

Der Umgang mit MRSA bei Beschäftigten im Gesundheitsdienst aus Sicht der Krankenhaushygiene

Background: Colonisation with methicillin-resistant Staphylococcus aureus (MRSA) is a particular challenge for medical staff and their facilities, with a key role being played by physicians alongside infection control and hospital hygiene professionals. Methods: In 2014, infection control and hygiene staff were surveyed on the handling of hospital staff with MRSA colonisation. The questionnaire queried on MRSA management in hospitals and on the cooperation between hygiene staff and hospital physicians and was compared to a survey of physicians' experience with the care of MRSA-positive hospital staff. Results: 124 hospital hygiene professionals participated in the survey. General screenings of staff members were reported mainly for cases of MRSA outbreak. Temporary colonisation is differentiated from permanent colonisation (47%). 2 unsuccessful attempts at decolonisation are normally regarded as an indicator for a permanent colonisation. Generally there was cooperation between hospital physicians and hygiene staff. The responsibility for screening and decolonisation of staff members is shared by both groups with the groups placing emphasis on different focal points. Different approaches for the handling of MRSA-positive staff were reported and recommendations for the work ability vary from merely observing the standard hygiene regulation to refraining from close patient contact or even complete absence from work. Conclusion: MRSA colonisation in hospital staff is being dealt with in different manners. Infection control and hospital hygiene professionals are equally involved in the treatment. Clear regulations would benefit the handling of MRSA in staff members.

Impact of different diagnostic technologies for MRSA admission screening in hospitals - a decision tree analysis.

BackgroundHospital infections with multiresistant bacteria, e.g., Methicillin-resistant Staphylococcus aureus (MRSA), cause heavy financial burden worldwide. Rapid and precise identification of MRSA carriage in combination with targeted hygienic management are proven to be effective but incur relevant extra costs. Therefore, health care providers have to decide which MRSA screening strategy and which diagnostic technology should be applied according to economic criteria.AimThe aim of this study was to determine which MRSA admission screening and infection control management strategy causes the lowest expected cost for a hospital. Focus was set on the Point-of-Care Testing (PoC).MethodsA decision tree analytic cost model was developed, primarily based on data from peer-reviewed literature. In addition, univariate sensitivity analyses of the different input parameters were conducted to study the robustness of the results.FindingsIn the basic analysis, risk-based PoC screening showed the highest mean cost savings with 14.98 € per admission in comparison to no screening. Rapid universal screening methods became favorable at high MRSA prevalence, while in situations with low MRSA transmission rates omission of screening may be favorable.ConclusionEarly detection of MRSA by rapid PoC or PCR technologies and consistent implementation of appropriate hygienic measures lead to high economic efficiency of MRSA management. Whether general or targeted screening is more efficient depends mainly on epidemiological and infrastructural parameters.

Factors related to the Management of MultiDrug-Resistant Organisms among Intensive Care Unit Nurses: An Application of the Health Belief Model*

Purpose: The purpose of this study was to identify factors which influence the management of MultiDrug-Resistant Organisms (MDROs) by nurses in Intensive Care Units (ICUs). Methods: Data were collected from December 8 to 20, 2013 and participants were 163 ICU nurses working in one general hospital. The Health Belief Model tool and knowledge and management of MDROs infection tools were used in the study. Descriptive statistics, t-test, analysis of variances, Pearson correlation coefficients and multiple regression were used to analyze the data. Results: Knowledge, perceived susceptibility, and perceived benefits had a significant influence on MRSA (Methicillin Resistant Staphylococcus Aureus,) and MDRAB (Multidrug Resistant Acinetobacter Baumannii) infection management when all the other variables were considered. Significant variable which had influence on VRE (Vancomycin Resistant Eenterococci) infection management were perceived susceptibility and perceived benefits. Conclusion: Perceived susceptibility and perceived benefits had significant influence on MDROs infection management. Emphasis needs to be on the perceived susceptibility and perceived benefits of MDROs infection management when providing an educational program for ICU nurses. 주요어: ë‹¤ì œë‚´ì„±, 감염관리, 중환자실, 간호사 Key words: Multiple drug resistance, Infection control, Intensive care unit, Nurses

Analysis of MRSA-attributed costs of hospitalized patients in Germany.

Infections with methicillin-resistant Staphylococcus aureus (MRSA) are assumed to have a high economic impact due to increased hygienic measures and prolonged hospital length of stay. However, surveys on the real expenditure for the prevention and treatment of MRSA are scarce, in particular with regard to the German Diagnosis-Related Groups (G-DRG) payment system. The aim of our study is to empirically assess the additional cost for MRSA management measures and to identify the main cost drivers in the whole process from the hospital's point of view. We conducted a one-year retrospective analysis of MRSA-positive cases in a German university hospital and determined the cost of hygienic measures, laboratory costs, and opportunity costs due to isolation time and extended lengths of stay. A total of 182 cases were included in the analysis. The mean length of hospital stay was 22.75days and the mean time in isolation was 17.08days, respectively. Overall, the calculated MRSA-attributable costs were <euro> 8,673.04 per case, with opportunity costs making up, by far, the largest share (77.45%). Our study provides a detailed up-to-date analysis of MRSA-attributed costs in a hospital. It allows a current comparison to previous studies worldwide. Moreover, it offers the prerequisites to investigate the adequate reimbursement of MRSA burden in the DRG payment system and to assess the efficiency of targeted hygienic measures in the prevention of MRSA.

Impact and Management of MRSA in the Long-Term Care Setting

Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of morbidity and mortality in healthcare facilities. Residents of nursing homes are commonly colonized with MRSA and acquisition within these facilities is common. While treatment of MRSA infection in the NH is more costly than treatment of infections caused by methicillin-susceptible strains, the frequency of serious infections and attributable mortality remains uncommon. Consequently, controlling the spread of MRSA in NHs is primarily a population health concern and interventions to control intrafacility transmissions should be balanced with a concern for resident quality-of-life.

Methicillin-Resistant Staphylococcus aureus in Obstetrics

Methicillin-resistant Staphylococcus aureus (MRSA) remains one of the major multiple antibiotic-resistant bacterial pathogens causing serious community-associated and health care-associated infections. It is now pervasive in the obstetric population associated with skin and soft tissue infections, mastitis, episiotomy, and cesarean wound infections and urinary tract infections. This review addresses the epidemiology, definitions, microbiology, and pathogenesis as well as common clinical presentations. A discussion of the 2011 Infectious Diseases Society of America MRSA treatment guidelines details available antibiotics, invasive and noninvasive MRSA management, and specific factors related to obstetrics. Finally, prevention strategies including decolonization are discussed.

Antibacterial and synergistic effects of Nardostachytis rhizoma extracts on methicillin-resistant Staphylococcus aureus

Methicillin-resistant Staphylococcus aureus (MRSA) is a serious clinical problem worldwide. Few new drugs are available against MRSA, because it has the ability to acquire resistance to most antibiotics which consequently increases the cost of medication. In the present study, the antibacterial activity of Nardostachytis rhizoma was investigated. The most effective method is to develop antibiotics from the natural products without having any toxic or side effects. Therefore, there is a need to develop alternative antimicrobial drugs for the treatment of infectious diseases. The use of two drugs in combination is a good alternative to slow the process of developing drug resistance and to restore the effectiveness of drugs that are no longer prescribed. Combination therapy is the most commonly recommended empirical treatment for bacterial infections in intensive care units, where monotherapy may not be effective against all potential pathogens, and for preventing the emergence of resistant. Five clinical isolates (MRSA) were obtained from five different patients at Wonkwang University Hospital (Iksan, South Korea). The other two strains were S. aureus ATCC 33591 (methicillin-resistant strain) and S. aureus ATCC 25923 (methicillin-susceptible strain). Antibacterial activity (minimal inhibitory concentrations, MICs) was determined by broth dilution method, disc diffusion method, MTT test and checkerboard dilution test. Antimicrobial activity of n-hexane fraction of N. rhizoma was significant. Against the seven strains, the disc diffusion test was in the range of 14 to 18 mm and had a MICs ranging from 31.25 to 125 ig/ml. FICI values for n-hexane fraction (HFL) of N. rhizome + ampicillin (AM) and HFL + oxacillin (OX) were 0.1875 and 0.078125-0.09375, showing the increase of synergistic effect. When combined together, these antibiotic effects were dramatically increased. These effective combinations could be new promising agents in the management of MRSA and MSSA. Key words : Nardostachytis rhizoma, synergism, antibacterial, methicillin-resistant Staphylococcus aureus (MRSA).

Methicillin-Resistant and Susceptible Staphylococcus aureus Bacteremia and Meningitis in Preterm Infants

Data are limited on the impact of methicillin-resistant Staphylococcus aureus (MRSA) on morbidity and mortality among very low birth weight (VLBW) infants with S aureus (SA) bacteremia and/or meningitis (B/M). Neonatal data for VLBW infants (birth weight 401-1500 g) born January 1, 2006, to December 31, 2008, who received care at centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network were collected prospectively. Early-onset (≤72 hours after birth) and late-onset (>72 hours) infections were defined by blood or cerebrospinal fluid cultures and antibiotic treatment of ≥5 days (or death <5 days with intent to treat). Outcomes were compared for infants with MRSA versus methicillin-susceptible S aureus (MSSA) B/M. Of 8444 infants who survived >3 days, 316 (3.7%) had SA B/M. Eighty-eight had MRSA (1% of all infants, 28% of infants with SA); 228 had MSSA (2.7% of all infants, 72% of infants with SA). No infant had both MRSA and MSSA B/M. Ninety-nine percent of MRSA infections were late-onset. The percent of infants with MRSA varied by center (P < .001) with 9 of 20 centers reporting no cases. Need for mechanical ventilation, diagnosis of respiratory distress syndrome, necrotizing enterocolitis, and other morbidities did not differ between infants with MRSA and MSSA. Mortality was high with both MRSA (23 of 88, 26%) and MSSA (55 of 228, 24%). Few VLBW infants had SA B/M. The 1% with MRSA had morbidity and mortality rates similar to infants with MSSA. Practices should provide equal focus on prevention and management of both MRSA and MSSA infections among VLBW infants.