Risk Of Methicillin-resistant Staphylococcus Aureus Infection Research Articles

Impact of New Methicillin-Resistant Staphylococcus aureus Carriage Postoperatively After Living Donor Liver Transplantation

Background Preoperative carriage of methicillin-resistant Staphylococcus aureus (MRSA) is associated with an increased risk of MRSA infection after liver transplantation. It is not known, however, whether new MRSA carriage postoperatively also increases the risk of MRSA infection after liver transplantation. Methods We retrospectively reviewed the data from 242 adult patients who underwent living donor liver transplantation (LDLT) including microbiological and medical records from admission to 3 months after LDLT. Uni and multivariate analyses were performed to identify independent risk factors for postoperative MRSA infection among preoperative noncarriers of MRSA. Results Postoperative MRSA infection occurred in 18 of 219 preoperative noncarriers of MRSA by median postoperative day 26. Operation time of at least 16 hours and postoperative colonization with MRSA independently predicted postoperative MRSA infection. Conclusion Postoperative surveillance cultures should be performed periodically after liver transplantation to identify high-risk candidates for postoperative MRSA infection, even among preoperative noncarriers of MRSA.

Glycopeptide pharmacokinetics in current paediatric cardiac surgery practice☆

To examine the evolution of serum concentrations of prophylactic glycopeptides administered during state-of-the-art cardiopulmonary bypass (CPB) and vigorous haemodiafiltration in paediatric patients undergoing cardiac surgery. We enrolled infants and children <3 years of age who, based on the preoperative microbiological screening, age and surgical complexity, were at high risk of methicillin-resistant Staphylococcus aureus (MRSA) infection. Antimicrobial prophylaxis with glycopeptides was administered to 22 patients, randomly assigned to vancomycin (VAN; n=11) versus teicoplanin (TEC; n=11). Fixed doses of each drug (15 mg/kg for VAN and 8 mg/kg for TEC) were administered immediately before the operation, at the time of priming of the extracorporeal circuit, upon admission to the intensive care unit and for 48 h thereafter, q. 8 h for VAN, and once daily for TEC. Vigorous haemodiafiltration was applied during and briefly after CPB. The second dose of drug added to the prime prevented a fall in serum drug concentrations at the onset of CPB in both groups. A 77% decrease in VAN, versus 53% in TEC concentrations, was observed after the conclusion of CPB. Serum concentrations of TEC>10 microg/ml were observed throughout the treatment period in 91% of patients, while 55% of patients assigned to VAN had serum concentrations consistently >5 microg/ml (p=0.08). Therapeutic serum concentrations were maintained throughout the intraoperative period, particularly with TEC, administered before the first surgical incision, followed by a supplemental bolus in the priming fluid of CPB. Postoperative surgical wound infections occurred in neither group. The prophylactic use of glycopeptides in paediatric patients at high risk of MRSA infection undergoing cardiac surgery was safe and effective. TEC might be the drug of choice, since stable, therapeutic serum concentrations were easily maintained throughout the treatment period.

Methicillin‐resistant Staphylococcus aureus infection after living‐donor liver transplantation in adults

Methicillin-resistant Staphylococcus aureus (MRSA) infection frequently complicates the postoperative course in deceased-donor liver transplantation. The incidence and risk factors of MRSA infection after Living-donor Liver transplantation (LDLT), however, are unclear. We retrospectively reviewed the data from 242 adult patients who underwent LDLT at the University of Tokyo Hospital. The microbiologic and medical records of the patients from admission to 3 months after LDLT were reviewed. Uni- and multivariate analyses were performed to identify the independent risk factors for postoperative MRSA infection. Postoperative MRSA infection occurred in 25 of 242 patients by median postoperative day 23. Preoperative MRSA colonization, preoperative use of antimicrobials, operation time (> or =16 h), and postoperative apheresis independently predicted postoperative MRSA infection. Surveillance culture should be checked periodically after admission to identify patients at high risk for MRSA infection and to administer appropriate antimicrobials for perioperative infection. Postoperative apheresis, suggesting postoperative liver dysfunction, predisposed patients to MRSA infection.

Methicillin-ResistantStaphylococcus aureusInfection and Colonization Among Hospitalized Prisoners

We assessed methicillin-resistant Staphylococcus aureus (MRSA) infection and colonization in hospitalized prisoners. Of 434 admission surveillance cultures, 58 (13%) were positive for MRSA. The sensitivity of admission surveillance cultures of samples from the anterior nares was 72% and increased to 84% when the calculation included cultures of wound samples. Hospitalized prisoners are at high risk for MRSA infection and colonization, and surveillance should include cultures of nares and wound samples.

Development of a Surveillance System for Methicillin-ResistantStaphylococcus aureusin German Hospitals

To determine the appropriate method to calculate the rate of methicillin-resistant Staphylococcus aureus (MRSA) infection and colonization (hereafter, MRSA rates) for interhospital comparisons, such that the large number of patients who are already MRSA positive on admission is taken into account. A prospective, multicenter, hospital-based surveillance of MRSA-positive case patients from January through December 2004. Data from 31 hospitals participating in the German national nosocomial infections surveillance system (KISS) were recorded during routine surveillance by the infection control team at each hospital. Data for 4,215 MRSA-positive case patients were evaluated. From this data, the following values were calculated. The median incidence density was 0.71 MRSA-positive case patients per 1,000 patient-days, and the median nosocomial incidence density was 0.27 patients with nosocomial MRSA infection or colonization per 1,000 patient-days (95% CI, 0.18-0.34). The median average daily MRSA burden was 1.13 MRSA patient-days per 100 patient-days (95% CI, 0.86-1.51), with the average daily MRSA burden defined as the total number of MRSA patient-days divided by the total number of patient-days times 100. The median MRSA-days-associated nosocomial MRSA infection and colonization rate, which describes the MRSA infection risk for other patients in hospitals housing large numbers of MRSA-positive patients and/or many patients who were MRSA positive on admission, was 23.1 cases of nosocomial MRSA infection and colonization per 1,000 MRSA patient-days (95% CI, 17.4-28.6). The values were also calculated for various MRSA screening levels. The MRSA-days-associated nosocomial MRSA rate allows investigators to assess the extent of MRSA colonization and infection at each hospital, taking into account cases that have been imported from other hospitals, as well as from the community. This information provides an appropriate incentive for hospitals to introduce further infection control measures.

Larval Therapy: A Novel Treatment in Eliminating Methicillin-Resistant Staphylococcus aureus From Diabetic Foot Ulcers

Overuse of antibiotics and the selection of broad- rather than narrow-spectrum agents have contributed to the high prevalence of methicillin-resistant Staphylococcus aureus (MRSA) colonization in diabetic foot wounds. Consequently, MRSA is now an endemic in both the community and hospital environments (1,2). We previously highlighted the problem (3) of MRSA colonization in our diabetic foot clinic (40% of S. aureus isolates were MRSA). A follow-up study (4) demonstrated that the number of foot wounds from which MRSA was isolated doubled in a 3-year period. Although terms such as critical colonization are not clearly defined, the risk of MRSA infection and bacteremia in patients with colonized ulcers is recognized (5,6). Furthermore, there is evidence (4) that MRSA colonization of chronic ulcers is associated with delayed healing times. Strategies to eliminate MRSA from colonized wounds are therefore essential and should include the use of simple, low-cost, effective treatments. Larval therapy is suggested (7) to successfully remove sloughy necrotic tissue from ulcers and to facilitate healing. We hypothesized that larval therapy would eradicate MRSA colonization from diabetic foot ulcers. Here, we report the results of our preliminary …

Randomized Controlled Trial of Chlorhexidine Gluconate for Washing, Intranasal Mupirocin, and Rifampin and Doxycycline Versus No Treatment for the Eradication of Methicillin-Resistant Staphylococcus aureus Colonization

Eradication of methicillin-resistant Staphylococcus aureus (MRSA) carriage may reduce the risk of MRSA infection and prevent transmission of the organism to other patients. To determine the efficacy of decolonization therapy, patients colonized with MRSA were randomized (3:1 allocation) to receive treatment (2% chlorhexidine gluconate washes and 2% mupirocin ointment intranasally, with oral rifampin and doxycycline for 7 days), or no treatment. Follow-up samples for MRSA culture were obtained from the nares, perineum, skin lesions, and catheter exit sites monthly for up to 8 months. The primary outcome measure was detection of MRSA at 3 months of follow-up. Univariate and multivariable analyses were performed to identify variables associated with treatment failure. Of 146 patients enrolled in the study, 112 patients (87 treated; 25 not treated) were followed up for at least 3 months. At 3 months of follow-up, 64 (74%) of those treated had culture results negative for MRSA, compared with 8 (32%) of those not treated (P=.0001). This difference remained significant at 8 months of follow-up, at which time, 54% of those treated had culture results negative for MRSA (chi2=64.4; P<.0001, by log-rank test). The results of the multivariable analysis indicated that having a mupirocin-resistant isolate at baseline was associated with treatment failure (relative risk, 9.4; 95% confidence interval, 2.8-31.9; P=.0003), whereas decolonization therapy was protective (relative risk, 0.1; 95% confidence interval, 0.04-0.4; P=.0002). Mupirocin resistance emerged in only 5% of follow-up isolates. Treatment with topical mupirocin, chlorhexidine gluconate washes, oral rifampin, and doxycycline for 7 days was safe and effective in eradicating MRSA colonization in hospitalized patients for at least 3 months.

Duration of Methicillin-Resistant Staphylococcus aureus Carriage, According to Risk Factors for Acquisition

To examine the duration of methicillin-resistant Staphylococcus aureus (MRSA) carriage and its determinants and the influence of eradication regimens. Retrospective cohort study. A 1,033-bed tertiary care university hospital in Bern, Switzerland, in which the prevalence of methicillin resistance among S. aureus isolates is less than 5%. A total of 116 patients with first-time MRSA detection identified at University Hospital Bern between January 1, 2000, and December 31, 2003, were followed up for a mean duration of 16.2 months. Sixty-eight patients (58.6%) cleared colonization, with a median time to clearance of 7.4 months. Independent determinants for shorter carriage duration were the absence of any modifiable risk factor (receipt of antibiotics, use of an indwelling device, or presence of a skin lesion) (hazard ratio [HR], 0.20 [95% confidence interval {CI}, 0.09-0.42]), absence of immunosuppressive therapy (HR, 0.49 [95% CI, 0.23-1.02]), and hemodialysis (HR, 0.08 [95% CI, 0.01-0.66]) at the time MRSA was first MRSA detected and the administration of decolonization regimen in the absence of a modifiable risk factor (HR, 2.22 [95% CI, 1.36-3.64]). Failure of decolonization treatment was associated with the presence of risk factors at the time of treatment (P=.01). Intermittent screenings that were negative for MRSA were frequent (26% of patients), occurred early after first detection of MRSA (median, 31.5 days), and were associated with a lower probability of clearing colonization (HR, 0.34 [95% CI, 0.17-0.67]) and an increased risk of MRSA infection during follow-up. Risk factors for MRSA acquisition should be carefully assessed in all MRSA carriers and should be included in infection control policies, such as the timing of decolonization treatment, the definition of MRSA clearance, and the decision of when to suspend isolation measures.

How to control the risk of MRSA infection

Methicillin-resistant Staphylococcus aureus (MRSA) infection is a serious national and global problem. Linda Nazarko looks at the effects of MRSA and the ways in which care home workers can prevent its spread.

Controlling the risk of MRSA infection: screening and isolating patients

Methicillin-resistant Staphylococcus aureus (MRSA) continues to be a major cause for concern to health boards and trusts through the UK and the rest of the world. A review of literature sourced via Cinahl, Medline and Pubmed examines the discussions for and against screening patients for MRSA and isolating MRSA-positive patients as a means of managing MRSA within the hospital setting. The research evidence available on the ability of MRSA strains to spread within the healthcare setting and how this influences the opposing arguments is explored. Other factors considered when examining the arguments for and against screening and isolation are: the implications both in cost and resources; the effect of MRSA infection on patient morbidity and mortality; and the need for individual risk assessment of MRSA colonized or infected patients to prevent the transmission of MRSA isolates. The arguments raised lead to the conclusion that screening and isolation should be universal to decelerate the rate of transmission of MRSA.

Reducing methicillin-resistant &lt;I&gt;Staphylococcus aureus&lt;/I&gt; (MRSA) patient exposure by infection control measures

To assess the effectiveness of infection control measures (pre-admission screening and patient segregation) on reducing in-patient exposure to methicillin-resistant Staphylococcus aureus (MRSA). A prospective case-control study in a district general hospital. All admissions to 3 wards over an 83-month period from September 1995 to July 2002 inclusive (a total of approximately 34,000 patients). Outcome measures were a statistical analysis of the difference in numbers of new cases of MRSA colonisation or infection between the 3 wards. There was a statistical significance in incidence of new MRSA cases between the ward with active infection control measures in place and the control wards. The described infection control measures reduced the exposure of patients to MRSA. This reduces the risk of MRSA infection, which is of importance in orthopaedics, and has further benefits that may also be applied in other surgical specialties.

Methicillin-resistant Staphylococcus aureus (MRSA) nares colonization at hospital admission and its effect on subsequent MRSA infection.

Asymptomatic colonization with methicillin-resistant Staphylococcus aureus (MRSA) has been described as a risk factor for subsequent MRSA infection. MRSA is an important nosocomial pathogen but has currently been reported in patients without typical risk factors for nosocomial acquisition. This study was designed to evaluate the impact of asymptomatic nares MRSA colonization on the development of subsequent MRSA infection. The incidence of MRSA infection was examined in patients with and patients without MRSA or methicillin-susceptible S. aureus (MSSA) colonization at admission to the hospital and in those who developed colonization during hospitalization. Patients admitted to 5 representative hospital units were prospectively evaluated. Nares samples were obtained for culture at admission and during hospitalization. Laboratory culture results were monitored to identify all MRSA infections that occurred during the study period and 1 year thereafter. Of the 758 patients who had cultures of nares samples performed at admission, 3.4% were colonized with MRSA, and 21% were colonized with MSSA. A total of 19% of patients with MRSA colonization at admission and 25% who acquired MRSA colonization during hospitalization developed infection with MRSA, compared with 1.5% and 2.0% of patients colonized with MSSA (P<.01) and uncolonized (P<.01), respectively, at admission. MRSA colonization at admission increased the risk of subsequent MRSA infection, compared with MSSA colonization (relative risk [RR], 13; 95% confidence interval [CI], 2.7-64) or no staphylococcal colonization (RR, 9.5; 95% CI, 3.6-25) at admission. Acquisition of MRSA colonization also increased the risk for subsequent MRSA infection, compared with no acquisition (RR, 12; 95% CI, 4.0-38). MRSA colonization of nares, either present at admission to the hospital or acquired during hospitalization, increases the risk for MRSA infection. Identifying MRSA colonization at admission could target a high-risk population that may benefit from interventions to decrease the risk for subsequent MRSA infection.

L’intérêt de l’isolement en secteur autonome des patients septiques, en Chirurgie Orthopédique et Traumatologique

To examine whether Sepsis Containment Units are presently in use by French Orthopedic surgeons in a number of hospitals and the subsequent efficacy of these measures in the prevention of risks linked to methicillin resistant Staphylococcus aureus (MRSA), MRSA was used as an example because it is the bacteria most frequently associated with infection in orthopedics. The transient carriage of MRSA on the hands of hospital personnel is the most common mechanism of patient to patient transmission. Consequently, the incidence of nosocomial MRSA in patients can be used to assess the quality of infection control. The orthopaedic surgery department (104 beds) of a 1. 228 bed, university affiliated public hospital located in eastern France (Besançon). First: a questionnaire was sent out to 71 French university orthopedic departments to investigate the practice in place. Second: to establish whether a significant correlation exists between the colonisation pressure exerted by real imported MRSA, and the number of cases of real acquired MRSA since we know that colonisation pressure of bacteria is a major factor in the prognosis of clinical infection. Third: our orthopedic surgery department was redesigned to study the risks of colonisation pressure with or without Sepsis Containment Units. First: among the 71 orthopedic departments studied, only 11 used a Sepsis Containment Unit. Second: there is a definite, linear relationship between the colonisation pressure exerted in a unit by real imported MRSA and the number of cases of real acquired clinical infection. Third: in the absence of Sepsis Containment Units, the risk of MRSA infections is increased by 160%. Debat: the classical clinical arguments concerning the dangers of hand or aerobic MRSA transmission are confirmed by our figures. The strict use of Sepsis Containment Units prevents contamination of septics by septics. Inversely, the rigorous concentration of means in the Sepsis Containment Units also prevents cross contamination of septics. At question are the psychological and financial inconveniences of Sepsis Containment Units. The results of this experiment, performed in orthopedic surgery, show that the use of Sepsis Containment Units is just as critical in other surgical units: vascular, thoracic, etc., nor should they be overlooked in outpatient and emergency care--often the first step in orthopedic surgery. Sepsis Containment Units are essential and merit further development.

Risk of methicillin-resistant Staphylococcus aureus infection after previous infection or colonization.

Studies evaluating the risk of methicillin-resistant Staphylococcus aureus (MRSA)-associated sequelae in colonized or infected inpatients have not extended follow-up into the period after discharge from the hospital. We determined the 18-month risk of MRSA infection among 209 adult patients newly identified as harboring MRSA. Twenty-nine percent of patients (60 patients) developed subsequent MRSA infections (90 infections). These infections were often severe. Twenty-eight percent of infections (25 of 90) involved bacteremia, and 56% (50 of 90) involved pneumonia, soft tissue infection, osteomyelitis, or septic arthritis. Eighty percent of patients (48 of 60) with subsequent MRSA infection developed the infection at a new site, and 49% of new MRSA infections (44 of 90) first became manifest after discharge from the hospital. Accurate assessment of the risk of MRSA-associated sequelae requires prolonged follow-up after discharge.

Community-Based Cluster of Methicillin-ResistantStaphylococcus Aureusin Manitoba

A community-based, single strain cluster of methicillin-resistant Staphylococcus aureus (MRSA) is described. The cluster of cases was identified in a small rural community in southwestern Manitoba, although some spread of the MRSA strain to neighbouring communities was observed. The majority of people were otherwise healthy, had no contact with the hospital system and did not fit the profile of those at risk for MRSA infection.

Risk factors for methicillin-resistant staphylococcus aureus (MRSA) infection in a Japanese geriatric hospital

A case control study on MRSA infection was carried out, with the purpose of evaluating the effect of age, gender, hypoalbuminemia, the limitation of activities of daily living (ADL), the administration of antibiotics and the use of the new cephems which include third generation cephalosporins and monobactam and carbapenems, on the occurrence of MRSA infection among the inpatients in a geriatric hospital. From April 1991 to March 1994, 285 patients underwent a bacterial culture in the various clinical aspects. 118 patients were positive for MRSA, who were then used as cases while 167 patients who were negative for MRSA were used as controls. The level of serum albumin and the ADL score were lower in the MRSA group than in the non-MRSA group ( P < 0.01) while the number of antibiotics administered before bacterial culture was greater in the MRSA group than in the non-MRSA group ( P < 0.01). The third generation cephems were more commonly used in the MRSA positive patients than the negative patients ( P < 0.01). Even after controlling for the other factors, hypoalbuminemia (OR = 1.73, 95% CI = 1.27–2.36), the limited ADL (partially limited vs without limitation: OR = 1.88, 95% CI = 1.19–2.96, completely limited vs without limitation: OR = 2.50, 95% CI = 1.64–3.82), the use of antibiotics other than the third generation cephems ( vs without antibiotics: OR = 1.73, 95% CI = 1.20–2.50) and the administration of the third generation cephems ( vs without antibiotics: OR = 3.12, 95% CI = 2.16–4.50) increased the risk of MRSA infection.

Incidence of Methicillin-resistant Staphylococcus Aureus (MRSA) Isolation in a Geriatric Hospital : A Second Report on the Risk Factors for the Occurrence of MRSA Infection in the Elderly

From April 1992 to March 1993, we examined the results of a bacterial culture from various clinical aspects in 83 elderly inpatients at a geriatric hospital. A case control study was carried out in order to evaluate the various factors which may influence the occurrence of methicillin-resistant Staphylococcus aureus (MRSA) infection. A univariate analysis revealed that a lower ADL score, a great number of antibiotics administration or the use of the third generation cephems increased the risk for MRSA infection. However, a multivariate analysis revealed that the risk for MRSA infection increased only among the patients who received the third generation cephems (OR: 2.80, 95% Cl : 1.40-5.63). Therefore, in the elderly, the use of third generation cephems seems to pose a great risk factor for MRSA infection. The level of total cholesterol, serum albumin or hemoglobin did not differ between the MRSA group and the non-MRSA group. However, among the patients who did not receive the third generation cephems, hypoalbuminemia was a risk for MRSA infection (OR: 2.06, 95% Cl : 1.10-3.85). J Epidemiol, 1994; 4 : 129-132.

Methicillin-resistant Staphylococcus aureus (MRSA) Infection in the Elderly

From April 1991 to March 1992, there were 117 elderly persons whose materials were examined for a bacterial culture in various clinical aspects. They consisted of 74 inpatients and 23 outpatients in a geriatric hospital, and 20 residents of a nursing home. The retrospective study was carried out in order to evaluate the various factors which may influence the occurence of methicillin-resistant Staphylococcus aureus (MRSA) infection in the elderly. The positive rate of MRSA was significantly greater for the inpatients (27.0%) than for the outpatients (0.0%) and the residents of a nursing home (5.0%). Compared to the MRSA negative inpatients, the MRSA positive inpatients had a lower ADL score (0.3*0.7 vs 1.4*1.2, p<0.05) and a larger amount of antibiotics prior to the bacterial culture (1.8*1.4 vs 0.8*1.3, p<0.05). After controlling for the confounding effects of age, length of hospitalization, ADL score and the administration of antibiotics, the risk of MRSA infection among the inpatients was increased in patients who could not either take meals, walk or use restroom by themselves (OR 2.24, 95% Cl 1.22-4.10) and in patients undergoing antibiotic therapy (OR 1.88, 95% Cl 1.03-3.44). In the elderly population, the disability to perform ADL seems to be one of the most important risk factor for MRSA infection. J Epidemiol, 1993; 3 : 117-120.