Evaluation of contact precautions for methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus

Cost Effectiveness of Screening for Methicillin-Resistant Staphylococcus aureus (MRSA) and Vancomycin-Resistant Enterococcus (VRE) in an Intensive Care Unit at a 200-Bed Community Hospital with Low Prevalence of These Antibiotic-Resistant Organisms

BackgroundMethicillin-resistant Staphylococcus aureus (MRSA) is a common pathogen of hospital infection with multi-drug resistant characteristics. Its spread and epidemic pose great challenges to nosocomial infection control. This study was aimed to identify risk factors for hospital-acquired MRSA (HA-MRSA) infections and investigate its clinical outcome, developing infection control strategies and improving patient outcomes.MethodsA retrospective case-case-control study was conducted to compare patients in Southwest Hospital, Chongqing, People's Republic of China from January 2018 to December 2018 with control patients. In this study, 251 patients with MRSA nosocomial infection, 339 patients with methicillin-sensitive Staphylococcus aureus strains (MSSA) nosocomial infection, and 300 patients with non-Staphylococcus aureus infection were included.ResultsMultivariate analysis showed that presence of central venous catheters (odds ratio [OR], 1.932; 95% confidence interval [CI], 1.074–3.477; P=0.028), sputum suction (OR, 2.887; 95% CI, 1.591–5.240; p<0.001), and total hospital stays more than 30 days (OR, 3.067; 95% CI, 2.063–4.559; P<0.001) were independent risk factors for HA-MRSA. Renal insufficiency (OR, 2.744; 95% CI, 1.089–6.914; P=0.032) and receipt of immunosuppressors (OR, 3.140; 95% CI, 1.284–7.678; P=0.012) were independent predictors of poor prognosis of MRSA nosocomial infection. Moreover, empirical use of antibiotics (OR, 0.514; 95% CI, 0.282–0.935; P=0.029) was a protective factor for poor prognosis of MRSA nosocomial infection. In-hospital mortality in the MRSA group was not statistically significant compared with the other two groups; however, the rate of poor prognosis in the MRSA group was higher than that of the MSSA group (27.5% vs 17.1%, χ2=9.200, P=0.002) and the control group (27.5% vs 16.0%, χ2=19.190, P=0.001).ConclusionOur results have shown presence of central venous catheters, sputum suction, and total hospital stays more than 30 days were associated with nosocomial MRSA infection. Patients with renal insufficiency and immunosuppressive therapy were more likely to cause poor prognosis with MRSA infection, and the empirical use of antibiotics can effectively reduce the adverse clinical outcomes caused by MRSA infection. Based on above findings, strategies to control MRSA infection should emphasize more attention to these patients and appropriate empirical use of antibiotics.

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

Surveillance of device-associated infections (DAIs) in intensive-care units (ICUs) is essential for a suitable healthcare strategy-planning. This study was conducted to determine the DAIs rate, microbial epidemiology, and antimicrobial resistance pattern (AMR) in ICU. Three major DAIs, ventilator associated pneumonia (VAP), catheter-associated urinary tract infection (CAUTI), and central line-associated bloodstream infection (CLABSI) were assessed prospectively during 6 months (2018 March 21 to September 22) in an 18-bed ICU of a tertiary teaching hospital in Tehran according to new CDC/NHSN definitions for surveillance of DAIs. The incidence of VAP, CAUTI, and CLABSI were 38.2, 8.9, and 13.5 per 1000 device-days respectively. The most organisms were Acinetobacter baumannii (34.9%), Klebsiella pneumonia (19%), E.coli (10.7%), Candida (10.7%), Enterococcus Spp. (8.7%), Pseudomonas aeruginosa (8.7%), and Staphylococcus aureus (2.9%). Klebsiella pneumoniae carbapenemase (KPC)-producing was 47.4%. Acinetobacter resistance to Ampicillin-sulbactam and carbapenems was 80.6% and more than 90% respectively. Methicillin resistant Staphylococcus aureus (MRSA) was 66.6% and Vancomycin-resistant Enterococcus (VRE) was 88.9%. This study showed high incidence of DAIs and resistant organisms in the ICU. Preventive measures are essential to decrease the rates.

Background:Deviceassociated infections (DAIs) increase the morbidity and mortality in the intensive care unit (ICU). Studies from the neurosurgical ICU in developing countries are sparse.Aims:The aim of this study was to assess the incidence of device-associated healthcare associated infections, pathogens isolated, antibiotic resistance, and mortality in neurosurgical ICU.Settings and Design:A retrospective study was conducted in the neurosurgical ICU of a tertiary care centerMaterials and Methods:This study was done by analyzing data of patients admitted in a neurosurgical ICU with one or more devices during the period from January 2011 to July 2017.Statistical Analysis:Quantitative variables were expressed as mean and standard deviation; qualitative variables were expressed as frequency and percentage.Results:During this period, 6788 patients with devices were admitted in the ICU, and 316 patients developed DAI. Two hundred and forty-eight patients had catheter-associated urinary tract infection (CAUTI), 78 had ventilator-associated pneumonia (VAP), and 53 had central line-associated bloodstream infection (CLABSI). The incidence rate for CAUTI was 17.83, VAP – 16.83, and CLABSI – 4.39 per 1000 device days. The device utilization ratio was highest for urinary catheter – 0.76, followed by central line – 0.66 and ventilator – 0.25. Predominant pathogens were Klebsiella – 90, Escherichia coli – 77, Pseudomonas – 40, Candida – 39, Acinetobacter – 30, and Enterobacter – 21. Carbapenem resistance was found in Acinetobacter (73.4%), Pseudomonas (45%), and Enterobacter (38%). S. aureus isolated in six cases; four being MRSA (66.7%). Multidrug resistance was found in Acinetobacter (80%), Pseudomonas (60%), Enterobacter (52.3%), Klebsiella (42.3%), and E. coli (33.7%). No colistin resistant Gram negative bacilli or vancomycin resistant enterococci were isolated. During this period 124 patients with DAI died, of which 52 patients had sepsis. The crude mortality rate was 1.83%.Conclusion:The DAI with the highest incidence was CAUTI, followed by VAP and CLABSI. With the implementation of insertion bundles and adherence to aseptic precautions, the DAI rate had come down.

Although methicillin-resistant Staphylococcus aureus (MRSA) nasal colonization is common among end-stage kidney disease patients undergoing haemodialysis, few studies were focused on MRSA nasal carriers among haemodialysis patients with central venous catheters (CVCs). The aim of this study is to evaluate the risk factors, various clinical outcomes and effect of decolonization for MRSA nasal colonization among patients on haemodialysis via CVCs. This was a single-centre non-concurrent cohort study of 676 patients who had new haemodialysis CVCs inserted. They were all screened for MRSA colonization via nasal swabs and were categorized into two groups: MRSA carriers and MRSA noncarriers. Potential risk factors and clinical outcomes were analysed in both groups. All MRSA carriers were given decolonization therapy and the effect of decolonization on subsequent MRSA infection was also performed. Eighty-two patients (12.1%) were MRSA carriers. Multivariate analysis showed that MRSA carrier (OR 5.44; 95% CI 3.02-9.79), long-term care facility resident (OR 4.08; 95% CI 2.07-8.05), history of Staphylococcus aureus infection (OR 3.20; 95% CI 1.42-7.20) and CVC in situ > 21days (OR 2.12; 95% CI 1.15-3.93) were independent risk factors for MRSA infection. There was no significant difference in all-cause mortality between MRSA carriers and noncarriers. The MRSA infection rates were similar between MRSA carriers with successful decolonization and those who had failed/incomplete decolonization in our subgroup analysis. MRSA nasal colonization is an important cause of MRSA infection among haemodialysis patients with CVCs. However, decolonization therapy may not be effective in reducing MRSA infection.

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) has posed a challenge in the treatment of neurosurgical patients. The authors investigated the impact of MRSA colonization and infection in the neurosurgical population at a community-based, tertiary care referral center. Hospitalized patients under the care of the Kaiser Permanente inpatient neurosurgery service were prospectively entered into a database. In Phase I of the study, 492 consecutive patients were followed. Per hospital policy, the 260 patients from this group who were admitted to the intensive care unit (ICU) underwent screening for MRSA based on nasal swab cultures and a review of their medical history for prior MRSA infections. These patients were designated as either MRSA positive (17 patients, 6.5% of screened patients) or MRSA negative (243 patients). The 232 patients admitted to non-ICU nursing units did not undergo MRSA screening and were designated as unscreened. In Phase II of the study, the authors reviewed 1005 neurosurgical admissions and completed a detailed chart review in 62 MRSA-positive patients (6.2%). Eleven patients received nonoperative treatment. Five patients presented with community-acquired neurosurgical infections, and the causative organism was MRSA in 3 cases. Forty-six patients underwent 55 procedures, and the authors reviewed their perioperative management. In Phase I of the study, the authors found that for the MRSA-positive, MRSA-negative, and unscreened groups, the rates of postoperative neurosurgical wound infections caused by all pathogens were 23.5, 4.1, and 1.3%, respectively. For MRSA wound infections, the rates were 23.5, 0.8, and 0%, respectively. In Phase II, patients with MRSA were noted to have the following clinical features: male sex in 63%, a malignancy in 39.1%, diabetes in 34.8%, prior MRSA infection in 21.7%, immunosuppressed state in 17.4%, and a traumatic injury in 15.2%. The rate of postoperative neurosurgical wound infection in patients who received MRSA-specific prophylactic antibiotic therapy (usually vancomycin) was 7.4% (27 procedures) compared with 32.1% (28 procedures) in patients who received the standard treatment (usually cefazolin) (p = 0.04). Wound care for ICU patients was standardized for postoperative Days 0-7 with chlorhexidine cleaning at bandage changes at 3-day intervals. Wound cultures from neurosurgical site infections in patients with prior MRSA colonization or infection grew MRSA in 7 of 11 patients. Neurosurgical patients identified with MRSA colonization or a prior history of MRSA infections benefit from specific perioperative care, including prophylactic antibiotics active against MRSA (such as vancomycin) and postoperative wound care with coverings and chlorhexidine antisepsis to reduce MRSA wound colonization.

Evaluating the Effectiveness of Contact Isolation in Preventing Healthcare-Associated Methicillin-Resistant Staphylococcus aureus Infection

Device-associated healthcare-associated infections (DA-HAIs) are the principal threat to patient safety in intensive care units (ICUs). The primary objective of this study was to identify the most common DA-HAIs in the pediatric intensive care unit (PICU) at the American University of Beirut Medical Center (AUBMC). Length of stay (LOS) and mortality, antimicrobial resistance patterns, and suitability of empiric antibiotic choices for DA-HAIs according to the local resistance patterns were also studied. This was a retrospective study that included all patients admitted to the PICU at AUBMC between January 2007 and December 2011. All patients admitted to the PICU having a placed central line, an endotracheal tube, and/or a Foley catheter were included. Data was extracted from the patients' medical records through chart review. A total of 22 patients were identified with 25 central line-associated bloodstream infections (CLABSI), 25 ventilator-associated pneumonia (VAP), and 9 catheter-associated urinary tract infections (CAUTIs). The causing organisms, their resistance patterns, and the appropriateness of empiric antimicrobial therapy were reported. Gram-negative pathogens were found in 53% of the DA-HAIs, Gram-positive ones in 27%, and fungal organisms in 20%. A total of 80% of K. pneumonia isolates were extended-spectrum beta-lactamases (ESBL) producers, and 30% of Pseudomonas isolates were multidrug resistant. No methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant enterococci (VRE) were isolated. Based on culture results, the choice of empiric antimicrobial therapy was appropriate in 64% of the DA-HAIs. After the care bundle approach is adopted in our PICU, DA-HAIs are expected to decrease further.

Background: Staphylococcus aureus is a major cause of serious hospital and community acquired infections, particularly in colonized individuals. Objectives: The study was carried out in a tertiary care center in Tehran, Iran to identify the frequency of hospital acquired methicillin resistant Staphylococcus aureus (HA-MRSA ) colonization and its antibiotic susceptibility pattern and molecular characteristics. Patients and Methods: This point-prevalence study was performed on 631 children who were admitted for at least 48 hours in different wards of Mofid childrens hospital in Tehran, Iran. Samples from anterior nares of these children were taken with sterile swab and cultured. If Staphylococcus aureus (S. aureus) was isolated, methicillin resistance and antibiotic susceptibility pattern were diagnosed according to Center for Disease Control and Prevention (CDC) guidelines of 2011 and Clinical and Laboratory Standards Institute (CLSI), and molecular analysis were determined by minimum inhibitory concentration (MIC) and polymerase chain reaction (PCR) methods. Results: Rate of colonization with S. aureus and methicillin resistant Staphylococcus aureus (MRSA) were 3.2% and 1.1% (1.1% of total and 35% of S. aureus isolates), respectively. All MRSA isolates were susceptible to rifampin and clindamycin. Resistance to vancomycin was reported in six Staphylococcus strains. Resistance to linezolid was detected in 19/20 Staphylococcus. Molecular analysis of isolates showed that all vancomycin resistant S. aureus isolates contained Van A or Van B gene, and 15/19 linezolid resistant strain was positive for chloramphenicol-florfenicol resistant gene ( cfr gene). Conclusions: The rate of MRSA colonization varies in any area, and the knowledge of acquisition risk factors and antibiotic susceptibility pattern are essential in prevention and treatment of MRSA infections. Based on our study, we suggest that clindamycin and rifampin are good choices in empiric treatment of patients suspected to have HA- MRSA infections until results of culture and antibiotic susceptibility pattern are prepared. In respect to the prevalence of linezolid resistance in this study, we suggest avoiding the use of linezolid as empiric therapy in HA-Staphylococcus infection.

BackgroundLinezolid is a new antimicrobial agent with a broad spectrum of activity against all clinically important gram positive bacteria, including methicillin resistant Staphylococcus aureus (MRSA) and vancomycin resistant enterococci (VRE)....

Choice of empiric antibiotic(s) for early ventilator associated pneumonia (VAP) involves weighing the risks of potential infection with multi-drug resistant (MDR) pathogens against those of over-exposure to broad-spectrum agents. Although early VAP is believed to be rarely caused by MDR pathogens, the overall incidence of all methicillin resistant Staphylococcus aureus (MRSA) infections is increasing. We questioned if MRSA VAP is becoming more common and if these infections were occurring earlier in the patient's hospital course. We hypothesized that 1) early (2-4 d from intubation) VAP caused by MRSA is relatively uncommon and 2) those patients with early VAP because of MRSA had risk factors associated with a MDR organism infection. Bronchoscopies with lavage (BALs) from patients admitted to our SICU from 2010-2013 were reviewed. MRSA VAP was defined as growth of ≥10(5) cfu/mL from BAL. Multi-drug resistant risk factors included a previous MRSA infection or positive nasal swab, antibiotic use within 90 d, hospitalization for >5 d, hemodialysis, homelessness, intravenous drug use, and men having sex with men. In the 3-y period, there were 438 cases of VAP. Forty-seven specimens from 43 patients had quantitative microbiologic confirmation of MRSA VAP for an overall prevalence of 10.7%. Of patients with early VAP, three of 106 (2.8%) were MRSA positive. Culture results were graphed according to ventilator days ( Fig. 1 ). The median days ventilated at the time of MRSA VAP were 8 d (range 2-81). All of the early MRSA VAP patients had identifiable risk factors for MRSA infection. The negative predictive value for patients not having a risk factor was one. These data suggest that the incidence of MRSA VAP is stable. Those patients with early MRSA VAP demonstrated traditional MDR risk factors. Patients without risk factors in the early time period could effectively be ruled out from having MRSA VAP and likely do not require empiric MRSA coverage.

Suspected horse-to-human transmission of MRSA ST398.

Introduction: Methicillin-resistant Staphylococcus aureus (MRSA) have been on the increase during the past decade, due to the steady growth of the elderly and immunocompromised patients, and the emergence of multidrug-resistant (MDR) bacterial strains. Although there are a limited number of anti-MRSA drugs available, a number of different combination antimicrobial drug regimens have been used to treat serious MRSA infections. Thus, the addition of several new antistaphylococcal drugs into clinical practice should broaden clinician's therapeutic options. As MRSA is one of the most common and problematic bacteria associated with increasing antimicrobial resistance, continuous efforts for the discovery of lead compounds as well as development of alternative therapies and faster diagnostics are required.Areas covered: This article summarizes the FDA-approved drugs to treat MRSA infections, the drugs in clinical trials, and the drug leads for MRSA and related Gram-positive bacterial infections. In addition, the article discusses the mode of action of antistaphylococcal molecules and the resistant mechanisms of some molecules.Expert opinion: The number of pipeline drugs presently undergoing clinical trials is not particularly encouraging. There are limited and rather expensive therapeutic options for MRSA infections in the critically ill. Further research efforts are required for effective phage therapy on MRSA infections in clinical use, which seem to be attractive therapeutic options for the future.

Background and Aims:Health-care-associated infection is a key factor determining the clinical outcome among patients admitted in critical care areas. The objective of the study was to ascertain the epidemiology and risk factors of health-care-associated infections in Intensive Care Units (ICUs) in a tertiary care hospital.Methods:This prospective, observational clinical study included patients admitted in ICU over a period of one and a half years. Routine surveillance of various health-care-associated infections such as catheter-associated urinary tract infections (CAUTI), central-line-associated blood stream infections (CLABSI), and ventilator-associated pneumonias (VAP) was done by the Department of Microbiology through specific Infection Surveillance Proforma.Results:Out of 679 patients, 166 suffered 198 episodes of device-associated infections. The infections included CAUTI, CLABSI, and VAP. The number of urinary tract infection (UTI) episodes was found to be 73 (10.75%) among the ICU patients who had indwelling urinary catheter. In addition, for 1 year CAUTI was calculated as 9.08/1000 catheter days. The number of episodes of blood stream infection was 86 (13.50%) among ICU patients having central line catheters. Also, CLABSI was found to be 13.86/1000 central line days. A total of 39 episodes (6.15%) of VAP was found in ICU patients over 18 months and VAP present for 6.04/1000 ventilator days.Conclusions:The organisms most commonly associated with health-care-associated infections were Pseudomonas aeruginosa and Acinetobacter species. The risk factors identified as being significantly associated with device associated infections in our ICU were diabetes, COPD and ICU stay for ≥8 days (P < 0.05).