Patterns and trends of pediatric bloodstream infections: a 7-year surveillance study.

We characterize the epidemiology of pediatric bloodstream infections (BSIs) in Switzerland. We analyzed pathogen distribution and resistance patterns in monomicrobial and polymicrobial BSIs in children from 2008 to 2014 using data from the Swiss antibiotic resistance centre (ANRESIS). A confirmatory statistical analysis was performed comparing pathogens and resistance across 20 acute care hospitals. We identified 3,067 bacteremia episodes, of which 1,823 (59 %) were considered true BSI episodes. Overall, S. aureus (16.5 %, 300) was the most frequent pathogen, followed by E. coli (15.1 %, 276), coagulase-negative staphylococci (CoNS, 12.9 %, 235), S. pneumoniae (11.1 %, 202) and non-E. coli Enterobacteriaceae (8.7 %, 159). S. aureus and E. coli showed similar frequencies in all of the variables analyzed (e.g., hospital acquisition, hospital type, medical specialty). The proportion of these microorganisms did not change over time, resistance rates remained low (4.3 % methicillin resistance in S. aureus; 7.3 % third-/fourth-generation cephalosporin resistance in E. coli), and no significant resistance trends were observed. We observed a 50 % increase of CoNS BSIs from 2008 (9.8 %, 27) to 2014 (15.2 %, 46, p value for trend = 0.03). S. pneumoniae decreased from 17.5 % (48) to 6.6 % (20) during that timeframe (p for trend = 0.007). S. aureus and E. coli remained the most significant pathogens among pediatric BSIs in Switzerland, exhibiting low resistance rates. CoNS accounted for a greater proportion of BSIs over time. The decrease in bacteremic pneumococcal infections can likely be attributed to the introduction of the 13-valent conjugate vaccine in 2011.

Rapid MRSA PCR on respiratory specimens from ventilated patients with suspected pneumonia: a tool to facilitate antimicrobial stewardship.

Methicillin-resistant Staphylococcus aureus (MRSA) is an important cause of pneumonia in ventilated patients. Our objective was to evaluate the GeneXpert MRSA/SA SSTI Assay (Xpert MRSA/SA) (Cepheid, Sunnyvale, CA) for use in lower respiratory tract (LRT) specimens for rapid MRSA detection and to determine the potentially saved antibiotic-days if a culture-based identification method was replaced by this assay. Remnant LRT samples from ventilated patients submitted to the microbiology laboratory for routine culture were tested using conventional culture and Xpert MRSA/SA. One hundred of 310 LRT specimens met the inclusion criteria. Ten samples were positive for MRSA by Xpert MRSA/SA, while six were positive by routine culture methods. Xpert MRSA/SA correctly identified 5/6 positive and 89/94 negative MRSA specimens, for a sensitivity of 83.3%, specificity of 94.7%, positive predictive value of 45.6%, and negative predictive value of 98.9%. The assay also correctly detected 3/3 positive and 90/97 negative methicillin-susceptible S. aureus (MSSA) specimens, for a sensitivity of 100%, specificity of 92.8%, positive predictive value of 30%, and negative predictive value of 100%. A total of 748 vancomycin and 305 linezolid antibiotic-days were associated with the enrolled specimens. Vancomycin and linezolid utilization could decrease by 68.4% and 83%, respectively, if discontinued 1 day after negative polymerase chain reaction (PCR) results. The Xpert MRSA/SA SSTI rapid MRSA PCR assay performed well in respiratory samples from ventilated patients with suspected pneumonia and has the potential to facilitate stewardship efforts such as reducing empiric vancomycin and linezolid therapy.

Daptomycin versus vancomycin for osteoarticular infections due to methicillin-resistant Staphylococcus aureus (MRSA): a nested case-control study.

Vancomycin is the standard antibiotic for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections. While daptomycin is approved for MRSA bacteremia, its effectiveness in osteoarticular infections (OAIs) has not been established. A 1:2 nested case-control study of adult patients with MRSA OAIs admitted to an academic center from 2005 to 2010 was carried out. Clinical outcomes and drug toxicity in patients treated with daptomycin versus vancomycin were compared. Twenty patients with MRSA OAIs treated with daptomycin were matched to 40 patients treated with vancomycin. The median age of the patients was 52 years (range, 25-90), and 40 (67%) were male. Most patients had osteomyelitis (82%), predominantly from a contiguous source (87%). Forty percent were diabetics. Diabetic patients were more likely to receive vancomycin than daptomycin [20 (50%) vs. 4 (20%); p = 0.03]. Vancomycin was more often combined with antibiotics other than daptomycin [22 (55%) vs. 5 (25%); p = 0.03]. The median total antibiotic treatment duration was 48 (daptomycin) vs. 46 days (vancomycin) (p = 0.5). Ninety percent of daptomycin-treated patients had previously received vancomycin for a median of 14.5 days (range, 2-36). Clinical success rates were similar between daptomycin and vancomycin at 3 months [15 (75%) vs. 27 (68%); p = 0.8] and 6 months [14 (70%) vs. 23 (58%); p = 0.5], even after propensity score-based adjustment for antibiotic assignment. The frequency of adverse events was similar between treatment groups [1 (5%) vs. 7 (18%); p = 0.2]. Daptomycin and vancomycin achieved similar rates of clinical success and drug tolerability. Daptomycin is a reasonable alternative for treating MRSA OAIs, particularly in patients where therapy with vancomycin has not been well tolerated.

Weekend diagnosis of Escherichia coli urinary tract infection does not predict poor outcome.

It has been suggested that mortality is higher in patients admitted to hospitals during the weekend. The objective of this study was to compare outcomes in patients with E. coli urinary tract infection (UTI) depending on the hospital admission day. For this purpose, a secondary analysis of data from a prospective cohort of patients with E. coli UTI was conducted. Weekend diagnosis of UTI was not associated with higher mortality. However, mortality was associated with sepsis, sepsis-induced hypotension and intensive care unit (ICU) admission. Sepsis-induced hypotension and ICU admission were independent determinants of mortality. The results indicate that indicators of severity of illness are associated with higher mortality in patients with UTI rather than the time of diagnosis.

Nasal carriage of methicillin-resistant Staphylococcus aureus (MRSA) among Swiss veterinary health care providers: detection of livestock- and healthcare-associated clones.

We screened a total of 340 veterinarians (including general practitioners, small animal practitioners, large animal practitioners, veterinarians working in different veterinary services or industry), and 29 veterinary assistants for nasal carriage of methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus pseudintermedius (MRSP) at the 2012 Swiss veterinary annual meeting. MRSA isolates (n = 14) were detected in 3.8 % (95 % CI 2.1 - 6.3 %) of the participants whereas MRSP was not detected. Large animal practitioners were carriers of livestock-associated MRSA (LA-MRSA) ST398-t011-V (n = 2), ST398-t011-IV (n = 4), and ST398-t034-V (n = 1). On the other hand, participants working with small animals harbored human healthcare-associated MRSA (HCA-MRSA) which belonged to epidemic lineages ST225-t003-II (n = 2), ST225-t014-II (n = 1), ST5-t002-II (n = 2), ST5-t283-IV (n = 1), and ST88-t186-IV (n = 1). HCA-MRSA harbored virulence factors such as enterotoxins, ß-hemolysin converting phage and leukocidins. None of the MRSA isolates carried Panton-Valentine leukocidin (PVL). In addition to the methicillin resistance gene mecA, LA-MRSA ST398 isolates generally contained additional antibiotic resistance genes conferring resistance to tetracycline [tet(M) and tet(K)], trimethoprim [dfrK, dfrG], and the aminoglycosides gentamicin and kanamycin [aac(6')-Ie - aph(2')-Ia]. On the other hand, HCA-MRSA ST5 and ST225 mainly contained genes conferring resistance to the macrolide, lincosamide and streptogramin B antibiotics [erm(A)], to spectinomycin [ant(9)-Ia], amikacin and tobramycin [ant(4')-Ia], and to fluoroquinolones [amino acid substitutions in GrlA (S84L) and GyrA (S80F and S81P)]. MRSA carriage may represent an occupational risk and veterinarians should be aware of possible MRSA colonization and potential for developing infection or for transmitting these strains. Professional exposure to animals should be reported upon hospitalization and before medical intervention to allow for preventive measures. Infection prevention measures are also indicated in veterinary medicine to avoid MRSA transmission between humans and animals, and to limit the spread of MRSA both in the community, and to animal and human hospitals.

Influence of environmental temperature and heatwaves on surgical site infection after hip and knee arthroplasty: a nationwide study.

BACKGROUND: Previous studies reported higher incidence of surgical site infection (SSI) after procedures performed in summer or with high temperatures. However, no study used detailed climate data to assess this risk after hip and knee arthroplasty, and no study specifically investigated the role of heatwaves. AIM: To assess the impact of higher environmental temperatures and heatwaves on SSI rates after hip and knee arthroplasty. METHODS: Data on hip and knee arthroplasty procedures performed between January 2013 and September 2019 in hospitals participating in the Swiss SSI surveillance were linked to climate data extracted from weather stations located in their vicinity. The association between temperature, heatwaves and SSI was studied using mixed effects logistic regression models fitted at the patient level. Poisson mixed models were fitted for both calendar year and month of the year to investigate the SSI incidence trajectory over time. RESULTS: We included 116,981 procedures performed in 122 hospitals. Significantly higher SSI rates were observed for procedures performed in the summertime (incidence rate ratio 1.39, 95% CI (1.20-1.60), P<0.001; reference: autumn) or in calendar months in which the mean temperature was above 20 °C (reference 5-10 °C; odds ratio 1.59, 95% CI (1.27, 1.98), P<0.001). We observed a slight but non-significant increase in the rate of SSI during heatwaves (1.44% versus 1.01%, P=0.2). CONCLUSION: SSI rates after hip and knee replacement appear to increase with higher environmental temperature. To establish whether, and to what extent, heatwaves increase the risk of SSI, studies involving geographical areas with larger variability in temperature are needed.

A Bayesian spatiotemporal model for prevalence estimation of a VRE outbreak in a tertiary care hospital.

BACKGROUND: There was a nosocomial outbreak of vancomycin-resistant enterococci (VRE) at the hospital between 1st January 2018 and 31st July 2020. The goals of this study were to describe weekly prevalence, and to identify possible effects of the introduction of selected infection control measures. METHODS: A room-centric analysis of 12 floors (243 rooms) of the main hospital building was undertaken, including data on 37,558 patients over 22,072 person-weeks for the first 2 years of the outbreak (2018-2019). Poisson Bayesian hierarchical models were fitted to estimate prevalence per room and per week, including both spatial and temporal random effects terms. RESULTS: Exploratory data analysis revealed significant variability in prevalence between departments and floors, along with sporadic spatial and temporal clustering during colonization 'flare-ups'. The oncology department experienced slightly higher prevalence over the 104-week study period [adjusted prevalence ratio (aPR) 4.8, 95% confidence interval (CI) 2.6-8.9; P<0.001; compared with general medicine], as did both the cardiac surgery (aPR 3.8, 95% CI 2.0-7.3; P<0.001) and abdominal surgery (aPR 3.7, 95% CI 1.8-7.6; P<0.001) departments. Estimated peak prevalence was reached in July 2018, at which point a number of new infection control measures (including the daily disinfection of rooms and room cleaning with ultraviolet light upon patient discharge) were introduced that resulted in decreasing prevalence (aPR 0.89 per week, 95% CI 0.87-0.91; P<0.001). CONCLUSION: Relatively straightforward but personnel-intensive cleaning with disinfectants and ultraviolet light provided tangible benefits in getting the outbreak under control. Despite additional complexity, Bayesian hierarchical models provide a more flexible platform to study transmission dynamics.

Prevalence and significance of bacterial contamination of autologous stem cell products.

There is limited and conflicting information on the prevalence of contamination of haematopoietic stem and progenitor cell products (HPCPs), and their optimal management remains unclear. The authors reviewed the microbial surveillance data of HPCPs collected between January 2002 and December 2019 for autologous transplantation at the study institution to determine the prevalence of microbial contamination and the potential infectious complications among recipients. Among 3935 HPCPs, 25 (0.6%) were contaminated. Ultimately, 22 patients received contaminated grafts, with pre-emptive antimicrobial therapy initiated in six of these patients. No patients developed subsequent infectious complications. These data suggest that microbial contamination of autologous HPCPs and associated adverse outcomes are rare.

Successful management of a Clostridioides difficile ribotype 027 outbreak with a lean intervention bundle.

BACKGROUND: In a 2015 point-prevalence study, Clostridioides difficile 027, a hypervirulent ribotype, was absent from healthcare institutions in Switzerland. In late 2016, we detected an outbreak of C. difficile infection (CDI) with ribotype 027 occurring across several hospitals in the same hospital network. METHODS: The first cases of CDI due to ribotype 027 triggered an outbreak investigation, including whole genome sequencing (WGS) to identify outbreak strains. FINDINGS: Twenty-eight patients with CDI caused by ribotype 027 between December 2016 and December 2017 were identified, out of which 20 were caused by a single clone. Commonalities among these patients were hospitalization in the same room or on the same ward, receiving care from the same healthcare workers, and shared toilet areas. In addition to the epidemiological links suggesting possible transmission pathways between cases, WGS confirmed the clonality of this C. difficile 027 outbreak. The outbreak was contained by isolation precautions, raising awareness among healthcare workers, harmonizing diagnostic algorithms, and switching to a sporicidal agent for environmental disinfection. Of note, neither default gowning and gloving nor hand washing with water and soap were implemented. CONCLUSION: This C. difficile 027 outbreak was recognized belatedly due to lack of screening for this ribotype in some hospitals, and was contained by a swift response with simple infection prevention measures and adapting the laboratory approach. In order to have a better understanding of C. difficile epidemiology, diagnostic approaches should be standardized, CDI declared notifiable, and longitudinal data on prevalent ribotypes collected in countries where this is not established.

Impact of an evidence-based intervention on urinary catheter utilization, associated process indicators, and infectious and non-infectious outcomes.

BACKGROUND: Multi-centre intervention studies tackling urinary catheterization and its infectious and non-infectious complications are lacking. AIM: To decrease urinary catheterization and, consequently, catheter-associated urinary tract infections (CAUTIs) and non-infectious complications. METHODS: Before/after non-randomized multi-centre intervention study in seven hospitals in Switzerland. Intervention bundle consisting of: (1) a concise list of indications for urinary catheterization; (2) daily evaluation of the need for ongoing catheterization; and (3) education on proper insertion and maintenance of urinary catheters. The primary outcome was urinary catheter utilization. Secondary outcomes were CAUTIs, non-infectious complications and process indicators (proportion of indicated catheters and frequency of catheter evaluation). FINDINGS: In total, 25,880 patients were included in this study [13,171 at baseline (August-October 2016) and 12,709 post intervention (August-October 2017)]. Catheter utilization decreased from 23.7% to 21.0% (P=0.001), and catheter-days per 100 patient-days decreased from 17.4 to 13.5 (P=0.167). CAUTIs remained stable at a low level with 0.02 infections per 100 patient-days (baseline) and 0.02 infections (post intervention) (P=0.98). Measuring infections per 1000 catheter-days, the rate was 1.02 (baseline) and 1.33 (post intervention) (P=0.60). Non-infectious complications decreased significantly, from 0.79 to 0.56 events per 100 patient-days (P<0.001), and from 39.4 to 35.4 events per 1000 catheter-days (P=0.23). Indicated catheters increased from 74.5% to 90.0% (P<0.001). Re-evaluations increased from 168 to 624 per 1000 catheter-days (P<0.001). CONCLUSION: A straightforward bundle of three evidence-based measures reduced catheter utilization and non-infectious complications, whereas the proportion of indicated urinary catheters and daily evaluations increased. The CAUTI rate remained unchanged, albeit at a very low level.

Detection of KPC-2 in a clinical isolate of Proteus mirabilis and first reported description of carbapenemase resistance caused by a KPC beta-lactamase in P. mirabilis.

An isolate of Proteus mirabilis recovered from blood cultures of a diabetic patient was shown to be resistant to imipenem, meropenem, and ertapenem by disk diffusion susceptibility testing. Amplification of whole-cell and/or plasmid DNA recovered from the isolate with primers specific for the bla(KPC) carbapenemase gene produced an amplicon of the expected size which was confirmed to be bla(KPC-2) by sequence analysis. Transformation of a susceptible Escherichia coli host with plasmid preparations from the isolate generated a transformant for which the MICs of all of the carbapenems tested were increased three- to fourfold. We believe this to be the first report of carbapenem resistance in P. mirabilis caused by the acquisition of bla(KPC).

Low incidence of subsequent bacteraemia or fungaemia after removal of a colonized intravascular catheter tip.

OBJECTIVES: We determined the frequency of subsequent bloodstream infection more than 2 days after removal of a catheter with positive tip cultures. METHODS: We conducted a nationwide, observational study on intravascular catheter (IVC) tip cultures in Switzerland from 2008 to 2015 using data from the Swiss Antibiotic Resistance Surveillance System (ANRESIS). An IVC tip culture was included in the analysis if at least one microorganism could be cultivated from it. We excluded all data from patients with concurrent bacteraemia with the same microorganism identified 7 days before to 2 days after IVC removal. Subsequent bloodstream infection was defined as isolating (from blood cultures performed more than 2 days up to 7 days after catheter removal) the same microorganism as the one recovered from the IVC. Data on antibiotic therapy were not available in this surveillance study. RESULTS: Over the 8-year period, 15 033 positive IVC tip cultures were identified. Our study population comprised 12 513 episodes of positive IVC tip cultures without concurrent bacteraemia. The frequency of sBSI was 1.8% (n = 219). Subsequent bloodstream infections were more frequently detected after identification of C. albicans (10/113, 8.8%), S. marcescens (9/169, 5.3%), and S. aureus (30/623, 4.8%) on a catheter tip. CONCLUSIONS: A very low incidence of subsequent bloodstream infection was observed if a microorganism was identified on a removed IVC tip without concurrent bacteraemia. The risk of subsequent bloodstream infection increased if C. albicans, S. aureus, or S. marcescens were identified in this context.

Characterizing non-linear effects of hospitalisation duration on antimicrobial resistance in respiratory isolates: an analysis of a prospective nationwide surveillance system.

OBJECTIVES: Our objective was to systematically study the influence of length of hospital stay on bacterial resistance in relevant respiratory tract isolates. METHODS: Using prospective epidemiological data from the National Swiss Antibiotic Resistance Surveillance System, susceptibility testing results for respiratory isolates retrospectively retrieved from patients hospitalised between 2008 and 2014 were compiled. Generalized additive models were used to illustrate resistance rates relative to hospitalisation duration and to adjust for co-variables. RESULTS: In all, 19 622 isolates of six relevant and predominant species were included. Resistance patterns for the predominant species showed a species-specific and antibiotic-resistance-specific profile in function of hospitalisation duration. The oxacillin resistance profile in Staphylococcus aureus isolates was constantly increasing (monophasic). The pattern of resistance to cefepime in Pseudomonas aeruginosa was biphasic with a decreasing resistance rate for the first 5 days of hospitalisation and an increase for days 6-30. A different biphasic pattern occurred in Escherichia coli regarding amoxicillin-clavulanic acid resistance: odds/day increased for the first 7 days of hospitalisation and then remained stable for days 8-30. In the adjusted models epidemiological characteristics such as age, ward type, hospital type and linguistic region were identified as relevant co-variables for the resistance rates. The contribution of these confounders was specific to the individual species/antibiotic resistance models. CONCLUSIONS: Resistance rates do not follow a dichotomic pattern (early versus late nosocomial) as suggested by current hospital-acquired pneumonia treatment guidelines. Duration of hospitalisation rather appears to have a more complex and non-linear relationship with bacterial resistance in hospital-acquired pneumonia, also depending on host and environmental factors.

Effect of music on surgical hand disinfection: a video-based intervention study.

Surgical hand disinfection (SHD) is likely to be influenced by various factors. The aim of this study was to evaluate the effect of listening to music on the duration of SHD. In total, 236 SHD procedures were recorded on video. The duration of SHD exceeded 2min in both the intervention group and the control group, with background music unable to achieve an increase in the time spent scrubbing. However, listening to music reduced the proportion of very short scrub times (<90s) from 17% to 9% (P=0.07). The following four factors increased mean scrub time significantly: female sex; lower staff seniority; scrubbing hands in groups; and use of a stopwatch. Although the improvement observed did not reach significance, it is suggested that background music may be useful for the 10% of healthcare workers who perform very short scrubs.

Overtreatment of asymptomatic bacteriuria: a qualitative study.

BACKGROUND: Overtreatment of asymptomatic bacteriuria (ASB) is widespread and may result in antibiotic side-effects, excess costs to the healthcare system, and may potentially trigger antimicrobial resistance. According to international management guidelines, ASB is not an indication for antibiotic treatment (with few exceptions). AIM: To determine reasons for using antibiotics to treat ASB in the absence of a treatment indication. METHODS: A qualitative study was conducted at a tertiary care hospital in Switzerland during 2011. We interviewed 21 internal medicine residents and attending physicians selected by purposive sampling, using a semi-structured questionnaire. Responses were analysed in an inductive thematic content approach using dedicated software (MAXQDA(®)). FINDINGS: In the 21 interviews, the following thematic rationales for antibiotic overtreatment of ASB were reported (in order of reporting frequency): (i) treating laboratory findings without taking the clinical picture into account (N = 17); (ii) psychological factors such as anxiety, overcautiousness, or anticipated positive impact on patient outcomes (N = 13); (iii) external pressors such as institutional culture, peer pressure, patient expectation, and excessive workload that interferes with proper decision-making (N = 9); (iv) difficulty with interpreting clinical signs and symptoms (N = 8). CONCLUSION: In this qualitative study we identified both physician-centred factors (e.g. overcautiousness) and external pressors (e.g. excessive workload) as motivators for prescribing unnecessary antibiotics. Also, we interpreted the frequently cited practice of treating asymptomatic patients based on laboratory findings alone as lack of awareness of evidence-based best practices.

Colonization with resistant microorganisms in patients transferred from abroad: who needs to be screened?

BACKGROUND: While multi-drug resistant organisms (MDRO) are a global phenomenon, there are significant regional differences in terms of prevalence. Traveling to countries with a high MDRO prevalence increases the risk of acquiring such an organism. In this study we determined risk factors for MDRO colonization among patients who returned from a healthcare system in a high-prevalence area (so-called transfer patients). Factors predicting colonization could serve as screening criteria to better target those at highest risk. METHODS: This screening study included adult patients who had been exposed to a healthcare system abroad or in a high-prevalence region in Switzerland over the past six months and presented to our 950-bed tertiary care hospital between January 1, 2012 and December 31, 2013, a 24-month period. Laboratory screening tests focused on Gram-negative MDROs and methicillin-resistant Staphylococcus aureus (MRSA). RESULTS: A total of 235 transfer patients were screened and analyzed, of which 43 (18 %) were positive for an MDRO. Most of them yielded Gram-negative bacteria (42; 98 %), with only a single screening revealing MRSA (2 %); three screenings showed a combination of Gram-negative bacteria and MRSA. For the risk factor analysis we focused on the 42 Gram-negative MDROs. Most of them were ESBL-producing Escherichia coli and Klebsiella pneumoniae while only two were carbapenemase producers. In univariate analysis, factors associated with screening positivity were hospitalization outside of Europe (p < 0.001), surgical procedure in a hospital abroad (p = 0.007), and - on admission to our hospital - active infection (p = 0.002), antibiotic treatment (p = 0.014) and presence of skin lesions (p = 0.001). Only hospitalization outside of Europe (Odds Ratio, OR 3.2 (95 % CI 1.5- 6.8)) and active infection on admission (OR 2.7 (95 % CI 1.07- 6.6)) remained as independent predictors of Gram-negative MDRO colonization. CONCLUSION: Our data suggest that a large proportion of patients (i.e., 82 %) transferred to Switzerland from hospitals in high MDRO prevalence areas are unnecessarily screened for MDRO colonization. Basing our screening strategy on certain criteria (such as presence of skin lesions, active infection, antibiotic treatment, history of a surgical procedure abroad and hospitalization outside of Europe) promises to be a better targeted and more cost-effective strategy.

Effectiveness of meticillin-resistant Staphylococcus aureus decolonization in long-term haemodialysis patients: a systematic review and meta-analysis.

BACKGROUND: Chronic haemodialysis patients are a high-risk population for meticillin-resistant Staphylococcus aureus (MRSA) colonization, which is a precursor of infection. AIM: To summarize the effect of nasal (± whole-body wash) MRSA decolonization in haemodialysis patients by means of a systematic review and meta-analysis. METHODS: We identified eligible studies using Medline, Embase, the Cochrane database, clinicaltrials.org, and conference abstracts investigating the success of MRSA decolonization in haemodialysis patients. For the statistical analysis, we used Stata 13 to express study-specific proportions with 95% confidence intervals. A likelihood ratio test was used to assess inter-study heterogeneity. FINDINGS: Six published prospective cohort studies and one study described in a conference abstract met our inclusion criteria. From 1150 haemodialysis patients enrolled in these studies, MRSA was isolated from nasal swabs of 147 (12.8%) patients. Six of the trials used mupirocin nasal ointment and combined it with chlorhexidine body washes for decolonization. The most widely used protocol was a five-day course of mupirocin nasal ointment application three times a day, and chlorhexidine body wash once daily. The pooled success rate of decolonization was 0.88 (95% confidence interval: 0.75-0.95). A likelihood ratio test of the fixed versus the random-effects model showed significant inter-study heterogeneity (P = 0.047). Four of seven studies determined subsequent MRSA infections in 94 carriers overall, two (2%) of which experienced infection. CONCLUSION: The use of mupirocin together with whole-body decolonization is highly effective in eradicating MRSA carriage in haemodialysis patients. The current literature, however, is characterized by a lack of comparative effectiveness studies for this intervention.

Low Yield of Methicillin-Resistant Staphylococcus aureus Screening in Hemodialysis Patients: 10 Years' Experience.

OBJECTIVE: To determine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) nasal colonization in hemodialysis patients and to analyze the cost-effectiveness of our screening approach compared with an alternative strategy. DESIGN Screening study and cost-effectiveness analysis. METHODS: Analysis of twice-yearly MRSA prevalence studies conducted in the hemodialysis unit of a 950-bed tertiary care hospital from January 1, 2004, through December 31, 2013. For this purpose, nasal swab samples were cultured on MRSA screening agar (mannitol-oxacillin biplate). RESULTS: There were 20 mass screenings during the 10-year study period. We identified 415 patients participating in at least 1 screening, with an average of 4.5 screenings per patient. Of 415 screened patients, 15 (3.6%) were found to be MRSA carriers. The first mass screening in 2004 yielded the highest percentage of MRSA (6/101 [6%]). Only 7 subsequent screenings revealed new MRSA carriers, whereas 4 screenings confirmed previously known carriers, and 8 remained negative. None of the carriers developed MRSA bacteremia during the study period. The total cost of our screening approach, that is, screening and isolation costs, was US $93,930. The total cost of an alternative strategy (ie, no mass screening administered) would be equivalent to costs of isolation of index cases and contact tracing was estimated to be US $5,382 (difference, US $88,548). CONCLUSIONS: In an area of low MRSA endemicity (<5%), regular nasal screenings of a high-risk population yielded a low rate of MRSA carriers. Twice-yearly MRSA screening of dialysis patients is unlikely to be cost-effective if MRSA prevalence is low.

Baseline hypovitaminosis D is not associated with poor clinical outcomes in osteoarticular infections.

OBJECTIVES: Although vitamin D is recognized as an important factor in bone health, its role in osteoarticular infections is unclear. We hypothesized that low vitamin D (25-hydroxycholecalciferol) levels are associated with a lower likelihood of treatment success in osteoarticular infections. METHODS: This was a retrospective cohort study of patients with orthopedic infections who had a 25-hydroxycholecalciferol level drawn when their infection was diagnosed. Outcomes were determined at early (3-6 months) and late (≥ 6 months) follow-up after completing intravenous antibiotics. RESULTS: We included 223 patients seen during an 11-month period with osteoarticular infections and baseline 25-hydroxycholecalciferol levels. During the initial inpatient management of the infection, hypovitaminosis D was identified and treated. The mean 25-hydroxycholecalciferol level was 23 ± 14 ng/ml; 167 (75%) patients had levels <30 ng/ml. Overall, infection treatment success was 91% (159/174) at early follow-up and 88% (145/164) at late follow-up. 25-Hydroxycholecalciferol baseline levels were similar in those with and without successful clinical outcomes, both at early (25 ± 15 vs. 21 ± 9 ng/ml; p=0.3) and late follow-up (25 ± 15 vs. 23 ± 16 ng/ml; p=0.6). CONCLUSIONS: To our knowledge this is the first report on hypovitaminosis D and its impact on outcomes of osteoarticular infections. Hypovitaminosis D was frequent in this cohort. With vitamin D repletion, there was no difference in treatment success whether patients had baseline hypovitaminosis or not.

Vancomycin resistance has no influence on outcomes of enterococcal bacteriuria.

BACKGROUND: Infections with vancomycin-resistant enterococci (VRE) are a growing concern in hospitals. The impact of vancomycin resistance in enterococcal urinary tract infection is not well-defined. AIM: To describe the epidemiology of enterococcal bacteriuria in a hospital and compare the clinical picture and patient outcomes depending on vancomycin resistance. METHODS: This was a 6-month prospective cohort study of hospital patients who were admitted with or who developed enterococcal bacteriuria in a 1250-bed tertiary care hospital. We examined clinical presentation, diagnostic work-up, management, and outcomes. FINDINGS: We included 254 patients with enterococcal bacteriuria; 160 (63%) were female and median age was 65 years (range: 17-96). A total of 116 (46%) bacteriurias were hospital-acquired and 145 (57%) catheter-associated. Most patients presented with asymptomatic bacteriuria (ASB) (119; 47%) or pyelonephritis (64; 25%); 51 (20%) had unclassifiable bacteriuria and 20 (8%) had cystitis. Secondary bloodstream infection was detected in 8 (3%) patients. Seventy of 119 (59%) with ASB received antibiotics (mostly vancomycin). There were 74 (29%) VRE bacteriurias. VRE and vancomycin-susceptible enterococci (VSE) produced similar rates of pyelonephritis [19 (25%) vs 45 (25%); P = 0.2], cystitis, and ASB. Outcomes such as ICU transfer [10 (14%) VRE vs 17 (9%) VSE; P = 0.3], hospital length of stay (6.8 vs 5.0 days; P = 0.08), and mortality [10 (14%) vs 13 (7%); P = 0.1] did not vary with vancomycin susceptibility. CONCLUSIONS: Vancomycin resistance did not affect the clinical presentation nor did it impact patient outcomes in this cohort of inpatients with enterococcal bacteriuria. Almost half of our cohort had enterococcal ASB; more than 50% of these asymptomatic patients received unnecessary antibiotics. Antimicrobial stewardship efforts should address overtreatment of enterococcal bacteriurias.