Clustering and risk factors of methicillin-resistant Staphylococcus aureus carriage in two Italian long-term care facilities

Colonization of Residents and Staff of an Italian Long-Term Care Facility and an Adjacent Acute Care Hospital Geriatrics Unit by Multidrug-Resistant Bacteria

In 2022, we undertook a point prevalence screening study for Enterobacterales with extended-spectrum β-lactamases (ESBLs), high-level AmpC cephalosporinases and carbapenemases, and also methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) in a long-term care facility (LTCF) and the associated acute-care hospital Geriatrics unit in Bolzano, Northern Italy. Urine samples and rectal, inguinal, oropharyngeal, and nasal swabs were plated on selective agar plates. Metadata of the patients, including demographic data, were collected, and risk factors for colonization were determined. ESBL, AmpC, carbapenemase, and quinolone resistance genes were investigated by the HybriSpot 12 PCR AUTO System. The following colonization percentages by multidrug-resistant (MDR) bacteria have been found in LTCF residents: all MDR organisms, 59.5%; ESBL producers, 46.0% (mainly CTX-M-type enzymes); carbapenemase producers, 1.1% (one Klebsiella pneumoniae with KPC-type); MRSA, 4.5%; VRE, 6.7%. Colonization by MDR bacteria was 18.9% for LTCF staff and 45.0% for Geriatrics unit patients. Peripheral vascular disease, the presence of any medical device, cancer, and a Katz Index of 0 were significant risk factors for colonization of LTCF residents by MDR bacteria in univariate and/or multivariate regression analysis. To conclude, the ongoing widespread diffusion of MDR bacteria in the LTCF suggests that efforts should be strengthened on MDR screening, implementation of infection control strategies, and antibiotic stewardship programs targeting the unique aspects of LTCFs. ClinicalTrials.gov ID: 0530250-BZ Reg01 30/08/2022.

Prevalence of indwelling urinary catheters in nursing home residents: Systematic review

BACKGROUND

This systematic review examines the prevalence of indwelling urinary catheters in nursing home residents.

METHODS

MEDLINE via PubMed, CINAHL, and EMBASE were searched from inception to 9 August 2022. Cross-sectional studies and longitudinal studies with cross-sectional analyses reporting catheter prevalence in nursing home residents were identified and summarized descriptively. Study quality was assessed using the Joanna Briggs Institute's tool.

RESULTS

Sixty-seven studies (92.5 % cross-sectional) were included. The reported number of included residents ranged from 73 to 110,656. The median catheter prevalence was 7.3 % (interquartile range 4.3-10.1 %; n = 65 studies). It was higher in Germany (10.2 % [9.7-12.8 %]; n = 15) than in the United States of America (9.3 % [6.3-11.9 %]; n = 9), United Kingdom (6.9 % [4.8-8.5 %]; n = 7), and Sweden (7.3 % [6.4-7.9 %]; n = 6). Furthermore, it was higher among men (17.0 % [16.0-26.0 %]) than among women (5.3 % [4.0-9.5 %]) (n = 9). Only one study investigated differences by age. The prevalence was higher for transurethral (5.7 % [5.6-7.2 %]; n = 12) than for suprapubic (1.2 % [0.6-2.5 %]; n = 13) catheters. Most catheterized residents were long-term catheterized (n = 6) and had their catheter changed within 3 months (n = 2). Symptomatic urinary tract infections were more common among catheterized than among non-catheterized residents (n = 4).

DISCUSSION

Catheter prevalence in nursing home residents varies between studies and countries. Prevalence differences by sex, age, and catheter type as well as duration of catheterization, catheter change intervals, and catheter-associated urinary tract infections are rarely reported because most studies do not primarily focus on catheters. Future studies should focus on the circumstances of urinary catheter use and care in nursing home residents.

REGISTRATION AND FUNDING

PROSPERO (29 August 2022; CRD42022354358); no funding.

Risk Factors and Prognosis of Carbapenem-Resistant Organism Colonization and Infection in Acute Cholangitis

Background

To identify the risk factors and prognosis of carbapenem-resistant organisms (CRO) in patients with acute cholangitis.

Methods

This retrospective observational study was conducted to explore the risk factors and prognosis of CRO infection in 503 acute cholangitis patients diagnosed between July 2013 and January 2022 at the First Affiliated Hospital of Chongqing Medical University, who were divided into a CRO group and non-CRO group based on the presence or absence of CRO. Univariate, multivariate analyses, and the proportional hazards model were used to compare the risk factors and prognosis of CRO suffering in patients with acute cholangitis.

Results

We identified 35 patients colonized with CRO from 503 acute cholangitis patients. In the multivariate analysis, tumor (OR=7.09, 95% CI=1.11-45.30, P=0.038) and chronic kidney disease (OR=8.70, 95% CI=2.11-35.88, P=0.003) were ascertained as the risk factors of the occurrence on CRO infection under the background of acute cholangitis. CRO infection was identified as an independent risk factor for acute cholangitis patient death (HR=5.147, 95% CI=1.475-17.595, P=0.01) by Cox proportional-hazards regression.

Conclusion

Tumor and chronic kidney disease may be risk factors for CRO infection. Patients diagnosed with acute cholangitis further infected with CRO had a poor prognosis and a more severe mortality. Active screening for CRO is expected to facilitate early prevention, diagnosis, and treatment of high-risk patients.

Barriers and facilitators of appropriate antibiotic use in primary care institutions after an antibiotic quality improvement program - a nested qualitative study

BACKGROUND

Antibiotic prescribing by physicians in primary care institutions is common and affected by several factors. Diagnosis and treatment of infections in a nursing home (NH) resident is challenging, with the risk of both under- and overtreatment. Identifying barriers and facilitators of appropriate antibiotic prescribing in NHs and municipal acute care units (MACUs) is essential to ensure the most adequate antibiotic treatment possible and develop future antibiotic stewardship programs.

METHODS

After implementing a one-year antibiotic quality improvement program, we conducted six semi-structured focus group interviews with physicians (n = 11) and nurses (n = 14) in 10 NHs and 3 MACUs located in the county of Østfold, Norway. We used a semi-structured interview guide covering multiple areas influencing antibiotic use to identify persistent barriers and facilitators of appropriate antibiotic prescribing after the intervention. The interviews were audio-recorded and transcribed verbatim. The content analysis was performed following the six phases of thematic analysis developed by Braun and Clarke.

RESULTS

We identified thirteen themes containing barriers and facilitators of the appropriateness of antibiotic use in primary care institutions. The themes were grouped into four main levels: Barriers and facilitators 1) at the clinical level, 2) at the resident level, 3) at the next of kin level, and 4) at the organisational level. Unclear clinical presentation of symptoms and lack of diagnostic possibilities were described as essential barriers to appropriate antibiotic use. At the same time, increased availability of the permanent nursing home physician and early and frequent dialogue with the residents' next of kin were emphasized as facilitators of appropriate antibiotic use. The influence of nurses in the decision-making process regarding infection diagnostics and treatment was by both professions described as profound.

CONCLUSIONS

Our qualitative study identified four main levels containing several barriers and facilitators of appropriate antibiotic prescribing in Norwegian NHs and MACUs. Diagnostic uncertainty, frequent dialogue with next of kin and organisational factors should be targeted in future antibiotic stewardship programs in primary care institutions. In addition, for such programs to be as effective as possible, nurses should be included on equal terms with physicians.

A longitudinal survey of methicillin-resistant Staphylococcus aureus carriage in nursing homes and the long-term care facility in Taiwan

BACKGROUND

We conducted a longitudinal survey for methicillin-resistant Staphylococcus aureus (MRSA) carriage in nursing homes and long-term care facilities (LTCFs) in northern Taiwan.

METHODS

From July 2016 to February 2017, healthcare workers and residents in four institutions were enrolled. One swab sample from nares and another swab sample from umbilicus were obtained from each participant for detection of MRSA at enrolment and then follow-up samples were collected every two months for additional three times if feasible.

RESULTS

We enrolled a total of 194 participants, including 127 residents and 67 healthcare workers. MRSA colonization rates were 23.2%, 22.8%, 20.7% and 18.6% at enrolment, the 2-, 4-, and 6-month follow-up survey, respectively, and the cumulative colonization rate was 40.2%. The MRSA detection rate was significantly higher at Institution 2 (70.7%) than that at other three institutions (25.7% ∼ 35%) (p < 0.001). Among 78 MRSA carriers, 45 were found to be colonized at enrolment, and other 33 were newly identified as MRSA colonization during follow-up. Of 172 MRSA isolates identified, there were two major clones, sequence types (ST) 45 (49.4%), and ST30 (25%). ST45 prevailed in three institutions and ST30 prevailed in two institutions.

CONCLUSIONS

Nearly one in five residents or healthcare workers in nursing homes and LTCFs harbored MRSA, mostly ST45 or ST30 strains, at any given time point in the study. The prevalence and molecular epidemiology of MRSA could vary in different institutions and molecular evidence for intra- and inter-institutional spread of MRSA was provided.

Prevalence and Risk Factors for Multidrug-Resistant Organisms Colonization in Long-Term Care Facilities Around the World: A Review

Elderly people confined to chronic care facilities face an increased risk of acquiring infections by multidrug-resistant organisms (MDROs). This review presents the current knowledge of the prevalence and risk factors for colonization by MDROs in long-term care facilities (LTCF), thereby providing a useful reference to establish objectives for implementing successful antimicrobial stewardship programs (ASPs). We searched in PubMed and Scopus for studies examining the prevalence of MDROs and/or risk factors for the acquisition of MDROs in LTCF. One hundred and thirty-four studies published from 1987 to 2020 were included. The prevalence of MDROs in LTCF varies between the different continents, where Asia reported the highest prevalence of extended-spectrum ß-lactamase (ESBL) Enterobacterales (71.6%), carbapenem resistant (CR) Enterobacterales (6.9%) and methicillin-resistant Staphylococcus aureus (MRSA) (25.6%) and North America the highest prevalence to MDR Pseudomonas aeruginosa (5.4%), MDR Acinetobacter baumannii (15.0%), vancomycin-resistant Enterococcus spp. (VRE) (4.0%), and Clostridioides difficile (26.1%). Furthermore, MDRO prevalence has experienced changes over time, with increases in MDR P. aeruginosa and extended spectrum ß-lactamase producing Enterobacterales observed starting in 2015 and decreases of CR Enterobacterales, MDR A. baumannii, VRE, MRSA and C. difficile. Several risk factors have been found, such as male sex, chronic wounds, the use of medical devices, and previous antibiotic use. The last of these aspects represents one of the most important modifiable factors for reducing colonization with MDROs through implementing ASPs in LTCF.

Association between length of residence and prevalence of MRSA colonization among residents in geriatric long-term care facilities

Background

A high prevalence of methicillin-resistant Staphylococcus aureus (MRSA) colonization has been reported among residents in geriatric long-term care facilities (LTCFs). Some studies indicate that MRSA might be imported from hospitals into LTCFs via resident transfer; however, other studies report that high MRSA prevalence might be caused by cross-transmission inside LTCFs. We aimed to assess which factors have a large impact on the high MRSA prevalence among residents of geriatric LTCFs.

Methods

We conducted a cohort study among 260 residents of four geriatric LTCFs in Japan. Dividing participants into two cohorts, we separately analyzed (1) the association between prevalence of MRSA carriage and length of LTCF residence (Cohort 1: n = 204), and (2) proportion of residents identified as MRSA negative who were initially tested at admission but subsequently identified as positive in secondary testing performed at ≥2 months after their initial test (Cohort 2: n = 79).

Results

Among 204 residents in Cohort 1, 20 (9.8%) were identified as positive for MRSA. Compared with residents identified as MRSA negative, a larger proportion of MRSA-positive residents had shorter periods of residence from the initial admission (median length of residence: 5.5 vs. 2.8 months), although this difference was not statistically significant (p = 0.084). Among 79 residents in Cohort 2, 60 (75.9%) were identified as MRSA negative at the initial testing. Of these 60 residents, only one (1.7%) had subsequent positive conversion in secondary MRSA testing. In contrast, among 19 residents identified as MRSA positive in the initial testing, 10 (52.6%) were negative in secondary testing.

Conclusions

The prevalence of MRSA was lower among residents with longer periods of LTCF residence than among those with shorter periods. Furthermore, few residents were found to become MRSA carrier after their initial admission. These findings highlight that MRSA in LTCFs might be associated with resident transfer rather than spread via cross-transmission inside LTCFs.

Recommendations for the surveillance of multidrug-resistant bacteria in Italian long-term care facilities by the GLISTer working group of the Italian Association of Clinical Microbiologists (AMCLI)

Long-term care facilities (LTCFs) are an important reservoir of multidrug-resistant organisms (MDROs). Colonization of LTCF residents by MDROs is generally higher in Italy compared to other European countries. The present review by the working group for the study of infections in LTCFs (GLISTer) of the Italian Association of Clinical Microbiologists (AMCLI) aims to propose criteria for a laboratory-based surveillance of MDROs in Italian LTCFs.

We recommend the adhesion to three levels of laboratory-based MDROs surveillance in LTCFs: i) mandatory MDRO surveillance by cumulative retrospective analysis of antimicrobial susceptibility data, obtained as part of routine care of clinical specimens. ii) strongly recommended surveillance by active rectal swab cultures or molecular screening to determine colonization with carbapenemase-producing Enterobacterales, should a resident be proven infected. iii) voluntary surveillance by prospective MDRO surveys, mainly based on point prevalence colonization studies, allowing to determine the MDROs baseline prevalence in the facility.

Laboratory-based surveillance of MDROs in LTCFs is aimed at providing useful epidemiological information to healthcare providers operating in the facility, but it is only effective if the collected data are used for infection prevention and control purposes, targeting the peculiar aspects of LTCFs.

Colonization of long-term care facility residents in three Italian Provinces by multidrug-resistant bacteria

Background

Rationale and aims of the study were to compare colonization frequencies with MDR bacteria isolated from LTCF residents in three different Northern Italian regions, to investigate risk factors for colonization and the genotypic characteristics of isolates. The screening included Enterobacteriaceae expressing extended-spectrum β-lactamases (ESβLs) and high-level AmpC cephalosporinases, carbapenemase-producing Enterobacteriaceae, Pseudomonas aeruginosa or Acinetobacter baumannii, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE).

Methods

Urine samples and rectal, inguinal, oropharyngeal and nasal swabs were plated on selective agar; resistance genes were sought by PCR and sequencing. Demographic and clinical data were collected.

Results

Among the LTCF residents, 75.0% (78/104), 69.4% (84/121) and 66.1% (76/115) were colonized with at least one of the target organisms in LTCFs located in Milan, Piacenza and Bolzano, respectively. ESβL producers (60.5, 66.1 and 53.0%) were highly predominant, mainly belonging to Escherichia coli expressing CTX-M group-1 enzymes. Carbapenemase-producing enterobacteria were found in 7.6, 0.0 and 1.6% of residents; carbapemenase-producing P. aeruginosa and A. baumannii were also detected. Colonization by MRSA (24.0, 5.7 and 14.8%) and VRE (20.2, 0.8 and 0.8%) was highly variable. Several risk factors for colonization by ESβL-producing Enterobacteriaceae and MRSA were found and compared among LTCFs in the three Provinces. Colonization differences among the enrolled LTCFs can be partially explained by variation in risk factors, resident populations and staff/resident ratios, applied hygiene measures and especially the local antibiotic resistance epidemiology.

Conclusions

The widespread diffusion of MDR bacteria in LTCFs within three Italian Provinces confirms that LTCFs are an important reservoir of MDR organisms in Italy and suggests that future efforts should focus on MDR screening, improved implementation of infection control strategies and antibiotic stewardship programs targeting the complex aspects of LTCFs.

[Community acquired urinary tract infections - association with risk factors : Changes in causative organisms and resistance over time]

BACKGROUND

Published studies on community-acquired urinary tract infections (UTI) often do not link microbiological findings with clinical risk factors and patient data.

MATERIALS AND METHODS

We retrospectively correlated clinical findings of all patients with UTI of a urological outpatient clinic with the respective microbiological analysis of their urine samples over 2 periods of time: (A: 2005-2006 and B: 2011-2012). Patients were stratified to the following risk groups: uncomplicated cystitis, diabetes mellitus type 2, nursing home resident, prostatitis/epidydimitis, permanent catheter.

RESULTS

The incidence of Escherichia coli (p < 0.001) and proteus (p < 0.001) significantly decreased from period A to B, while enterococci (p = 0.003) and staphylococci (p < 0.001) significantly increased. Antibiotic sensitivity to fosfomycin (p < 0.001), doxycycline (p < 0.001), nitrofurantoin (p < 0.001), and nitroxoline increased (p < 0. 001) and sensitivity to amoxicillin (p < 0.001) and gentamicin decreased (p < 0.001). Patients with a permanent catheter had significantly poorer sensitivity rates (50% and less) for almost all antibiotics tested compared to the overall group. The risk of a UTI with 3MRGN or MRSA bacteria was significantly higher for catheter carriers and nursing home residents.

CONCLUSIONS

Empiric antibiotic first-line therapy with nitrofurantoin and fosfomycin for uncomplicated community acquired UTIs are well indicated in conformity with guidelines. The accumulation of multiresistant pathogens in patients with a permanent bladder catheter requires restrictive use of any permanent catheter drainage.

Incidence of Methicillin-Resistant Staphylococcus aureus (MRSA) Carrier Status in Patients Undergoing Post-Mastectomy Breast Reconstruction

BACKGROUND

The incidence of methicillin-resistant Staphylococcus aureus (MRSA) carriers and infections continues to rise. Some specialties have demonstrated a reduction in infection through appropriate screening and treatment.

OBJECTIVES

We sought to investigate the incidence of preoperative colonization, postoperative conversion, and whether this had any impact on outcomes in patients undergoing post-mastectomy breast reconstruction (BR).

METHODS

This is a prospective study of a series of 122 BR patients from a single surgeon from May 2013 to March 2015. Nasal swabs were obtained at preoperative and postoperative clinic visits. The incidence of preoperative and postoperative colonization, demographic, and clinical variables were analyzed and compared to complication rates within 90 days of surgery.

RESULTS

The incidence of MRSA colonization was 3.3% (n = 4) preoperatively and 4.1% (n = 5) postoperatively. One patient was positive at both time points, and 4 patients converted postoperatively. Preoperative or postoperative colonization with MRSA was not associated with any specific patient demographics. Hospital length of stay tended to be longer in patients colonized both preoperatively (2.8 days vs 1.6 days, P = .075) and postoperatively (2.8 days vs 1.8 days, P = .072). Postoperative colonization trended toward an increased incidence of any complication (80.0% vs 35.7%, P = .068) and was significantly associated with delayed wound healing (40.0% vs 4.8%, P = .035). Having a minor complication (P = .073) and implant exposure (P = .056) tended to be associated with postoperative carriers.

CONCLUSIONS

The incidence of MRSA in breast reconstruction patients is relatively low, yet complications rates are higher in those patients. Multicenter randomized trials should be conducted to determine if there is a role for preoperative screening and treatment of MRSA carriers.

LEVEL OF EVIDENCE

2 Risk.

Review on colonization of residents and staff in Italian long-term care facilities by multidrug-resistant bacteria compared with other European countries

BACKGROUND

Rates of colonization and infection with multidrug-resistant (MDR) bacteria are increasing worldwide, in both acute care hospitals and long-term care facilities (LTCFs). Italy has one of the highest prevalence of MDR bacteria in European countries, especially with regard to methicillin-resistant Staphylococcus aureus (MRSA) and extended-spectrum β-lactamase (ESBL) or carbapenemase producing Enterobacteriaceae (CPE).

METHOD

Review of studies on colonization by MDR bacteria from Italian LTCFs, risk factors for colonization and molecular characteristics of surveillance and clinical isolates, compared with other European countries.

RESULTS

High variability of MDR colonization has been reported within and especially between European countries. Only a few surveillance studies have been performed in Italian LTCFs; these show MRSA colonization prevalence of 7.8-38.7 % for residents and 5.2-7.0 % for staff members, ESBL prevalence of 49.0-64.0 % for residents and 5.2-14.5 % for staff and prevalence of CPE of 1.0-6.3 % for residents and 0.0-1.5 % for staff. In Italian LTCFs, as well as in other European countries, the most prevalent ESBLs from surveillance or clinical Escherichia coli isolates were found to be CTX-M-type enzymes, particularly CTX-M-15, expressed by the pandemic ST131 clonal group; this lineage also expresses carbapenemase genes of the blaVIM and blaKPC types. Various risk factors for colonization of residents by MDR bacteria were identified.

CONCLUSIONS

The limited data from Italian LTCFs confirms these settings as important reservoirs for MDR organisms, allowing important considerations regarding the infection risk by these organisms. Nevertheless, more extended and countrywide screening studies for MDR colonization in Italian LTCFs are required. To promote further studies of various microbiological aspects related to LTCFs, the Association of Italian Clinical Microbiologists (Associazione Microbiologi Clinici Italiani; AMCLI) in 2016 has set up a new Working Group for the Study of Infections in LTCFs (Gruppo di Lavoro per lo Studio delle Infezioni nelle Residenze Sanitarie Assistite e Strutture Territoriali assimilabili; GLISTer), consisting of Clinical Microbiologists represented by the authors of this review article.

Risk factors for methicillin-resistant Staphylococcus aureus carriage among residents in 7 nursing homes in Shanghai, China

BACKGROUND

Nursing home residents are a population at risk for methicillin-resistant Staphylococcus aureus (MRSA) carriage, but few data about MRSA in this setting in Shanghai are available. The aim of this study is to determine the prevalence and risk factors for MRSA carriage in nursing home residents in Shanghai, China.

METHODS

Four hundred forty-three residents from 7 nursing homes in Shanghai, China, participated in this study; nasal and axillary swabs were obtained from these residents. Laboratory identification for S aureus and antimicrobial susceptibility testing were performed when isolated. Data, including individual resident characteristics and nursing home characteristics, were collected and analyzed.

RESULTS

Of the 443 participating residents, 99 (22.3%) and 45 (10.2%) residents were colonized by S aureus and MRSA, respectively. Previous hospitalization (odds ratio [OR], 2.564; 95% confidence interval [CI], 1.214-5.415; P = .014), presence of an invasive device (OR, 3.455; 95% CI, 1.678-7.113; P = .001), chloramphenicol therapy (OR, 7.672; 95% CI, 1.807-32.580; P = .006), and macrolides therapy (OR, 2.796; 95% CI, 1.056-7.403; P = .038) were independent risk factors for MRSA colonization. Low expenditure per month and less good sanitary condition also increased the risk for MRSA colonization.

CONCLUSIONS

Our study suggests that nursing homes are significant reservoirs for MRSA. Implementation of infection control strategies must be given high priority in nursing homes to fight the high prevalence of MRSA, and increased convenience and feasibility should also be realized with these control strategies for MRSA colonization.

Molecular and phenotypic characterization of methicillin-resistant Staphylococcus aureus isolates from a tertiary hospital in the Philippines

Background

Methicillin-resistant Staphylococcus aureus (MRSA) poses a major threat to public health worldwide. There are relatively few studies addressing the molecular epidemiology of MRSA in the Philippines.

Methods

This study characterized MRSA isolates in terms of their antimicrobial susceptibility profile, the SCCmec type, and the presence of lukF-lukS genes for Panton-Valentine leukocidin (PVL) and determined the relatedness of the isolates by random amplified polymorphic DNA (RAPD)-polymerase chain reaction (PCR).

Results

A total of 236 S. aureus were isolated from clinical specimens of the Makati Medical Center in Makati City, Philippines, between January 2013 and June 2013, and 108 or 45.76 % were found to be MRSA. Results showed that the MRSA strains were resistant to trimethoprim-sulfamethoxazole (20.37 %), azithromycin (10.19 %), gentamicin (5.56 %), and linezolid (4.63 %), while all were susceptible to vancomycin, nitrofurantoin, levofloxacin, minocycline, rifampin, and tetracycline. One isolate was found positive for inducible clindamycin resistance. All of the 108 MRSA strains were confirmed to carry the mecA and SCCmec genes, while the PVL genes were detected in 41 (38 %) of the isolates. Ninety-six isolates (89 %) carried SCCmec type IV, while the remaining isolates carried SCCmec type I (11 isolates) or type III (one isolate).

Conclusion

This study is the first to present a comprehensive MRSA surveillance data with molecular characterization in a tertiary hospital in the Philippines.

Prevalence and Molecular Epidemiology of Staphylococcus aureus among Residents of Seven Nursing Homes in Shanghai

BACKGROUND

Residents in nursing homes (NHs) always represent potential reservoirs for Staphylococcus aureus and methicillin-resistant S. aureus (MRSA). To our knowledge, there is no epidemiological information up till now that describes the prevalence and molecular characteristics of S. aureus in nursing home residents in Shanghai, China.

METHODS

Four hundred and ninety-one unique residents from 7 NHs were enrolled in this study. Specimens were collected among these residents including 491 nasal swabs, 487 axillary swabs and 119 skin swabs. S. aureus isolated and identified from the swabs was characterized according to antimicrobial susceptibility profiling, toxin gene prevalence, and multilocus sequence typing (MLST), spa and SCCmec typing.

RESULTS

Among the 491 residents screened, S. aureus was isolated in 109 residents from 90 nasal swabs (90/491, 18.3%), 29 axillary swabs (29/487, 6.0%), and 22 skin swabs (22/119, 18.5%). Sixty-eight MRSA isolates were detected in 52 residents from 41 nasal carriers, 15 axillary carriers and 12 skin carriers. The overall prevalence rate of S. aureus and MRSA colonization was 22.2% and 10.6% respectively. Ten residents presented S. aureus in all three sample types and 12 residents presented S. aureus in two of the three sample types collected. Molecular analysis revealed CC1 (29.1%) to be the dominant clone in this study, followed by CC398 (19.9%), CC188 (13.5%) and CC5 (12.8%). The most common spa type was t127 (22.0%), followed by t14383 (12.8%) and t002 (10.6%).

CONCLUSIONS

A high prevalence of S. aureus and MRSA colonization was revealed in nursing home residents in Shanghai. CC1 was the most common clonal complex and t127 was the most common spa type among NH residents. The data provides an important baseline for future surveillance of S. aureus in NHs in Shanghai and other highly urbanized regions in China. Implementation of infection control strategies must be given high priority in NHs to fight such high prevalence of both MRSA and methicillin-susceptible S. aureus (MSSA).

Current prevalence of multidrug-resistant organisms in long-term care facilities in the Rhine-Main district, Germany, 2013

Multidrug-resistant organisms (MDRO) and in particular multidrug-resistant Gram-negative organisms (MRGN) are an increasing problem in hospital care. However, data on the current prevalence of MDRO in long-term care facilities (LTCFs) are rare. To assess carriage rates of MDRO in LTCF residents in the German Rhine-Main region, we performed a point prevalence survey in 2013. Swabs from nose, throat and perineum were analysed for meticillin-resistant Staphylococcus aureus (MRSA), perianal swabs were analysed for extended-spectrum beta-lactamase (ESBL)-producing organisms, MRGN and vancomycin-resistant enterococci (VRE). In 26 LTCFs, 690 residents were enrolled for analysis of MRSA colonisation and 455 for analysis of rectal carriage of ESBL/MRGN and VRE. Prevalences for MRSA, ESBL/MRGN and VRE were 6.5%, 17.8%, and 0.4%, respectively. MRSA carriage was significantly associated with MRSA history, the presence of urinary catheters, percutaneous endoscopic gastrostomy tubes and previous antibiotic therapy, whereas ESBL/MRGN carriage was exclusively associated with urinary catheters. In conclusion, this study revealed no increase in MRSA prevalence in LTCFs since 2007. In contrast, the rate of ESBL/MRGN carriage in German LTCFs was remarkably high. In nearly all positive residents, MDRO carriage had not been known before, indicating a lack of screening efforts and/or a lack of information on hospital discharge.

[Healthcare associated infections (HAI), antibiotic use and prevalence of multidrug-resistant bacteria (MDRO) in residents of long-term care facilities: the Frankfurt HALT plus MDRO project 2012]

BACKGROUND

Residents of long-term care facilities (LTCF) are at risk of healthcare associated infections (HAI) and are often treated with antibiotics. In Germany a current HAI prevalence of 1.6 % and antibiotic use in 1.15% have been reported. However, data published on the current prevalence of multidrug-resistant organisms (MRDO) in LTCFs in Germany are scarce. Therefore, the prevalence of HAI, antibiotic use and presence of MDROs were investigated in LTCF residents in Frankfurt am Main, Germany.

METHODS

A point prevalence study of HAI and antibiotic use according to the European HALT protocol (health care associated infections in long-term care facilities) was carried out; swabs from the nose, throat and perineum were analyzed for methicillin-resistant Staphylococcus aureus (MRSA), extended spectrum beta-lactamase producing enterobacteria (ESBL) and vancomycin-resistant enterococci (VRE).

RESULTS

A total of 880 residents in 8 LTCFs were enrolled in the study in 2012. The study participants were 30% male, 46.7%  were more than 85 years old, 70% exhibitied urinary or fecal incontinence, 11.4% had an indwelling urinary catheter and 0.1% a vascular catheter. Prevalence rates of HAI and of antibiotic use were 2.5 % and 1.5%, respectively. The prevalence of MDROs in 184 residents who agreed to being tested for MDROs was 9.2% MRSA, 26.7% ESBL and 2.7% VRE.

CONCLUSION

The HAIs and antibiotic use were comparable to the German HALT data from 2010. Compared to other German studies there is a steadily increasing MRSA problem in German LTCFs. High and increasing ESBL rates have been detected in German LTCFs. Further studies are needed to confirm this trend, preferably encompassing molecular methods to study epidemiology.

Dissemination of methicillin-resistant Staphylococcus aureus sequence type 45 among nursing home residents and staff in Taiwan

Unlike hospitals or the community, nursing homes provide a unique healthcare environment for patients. There have been no reports regarding methicillin-resistant Staphylococcus aureus (MRSA) carriage among nursing home residents and staff in Taiwan. From May to November 2012, a total of 523 subjects, including 360 residents and 163 staff, in 14 nursing homes in Taiwan were surveyed for nasal MRSA carriage. Overall, the nasal MRSA carriage rate was 20.1%, with 20.3% for residents and 19.6% for staff. For residents, age >60 years (adjusted OR 2.268; 95% CI 1.185-4.342; p 0.013) and the presence of chronic wounds (adjusted OR 2.449; 95% CI 1.082-5.544; p 0.032) were the significant risk factors for MRSA carriage in multivariate models. Among the 105 MRSA isolates, 11 pulsed-field gel electrophoresis (PFGE) patterns were identified, except for five isolates untypeable by SmaI digestion, with one major pattern; nine isolates (8.6%) possessed staphylococcal cassette chromosome (SCCmec) type II or III, 66 isolates type IV or V, and 21 isolates unidentified types. The clone characterized as PFGE pattern BM sequence type 45 was the most common clone, accounting for 50% of the isolates, and was multiresistant, including to ciprofloxacin. Intra-institutional and inter-institutional transmission of MRSA was documented by molecular methods. It was shown conclusively that one-fifth of residents and staff in nursing homes in Taiwan harboured MRSA, mostly ST45 strains, in their nares. Intra-institutional and inter-institutional transmission of MRSA was documented.

Prevalence of multidrug-resistant organisms and risk factors for carriage in long-term care facilities: a nested case-control study

BACKGROUND

Long-term care facilities (LTCFs) are a potentially important reservoir of multidrug-resistant (MDR) organisms; however, limited data exist.

METHODS

A point-prevalence study was conducted in four co-located LTCFs in Australia. Nasal and rectal swabs were cultured for methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE) and MDR Gram-negative bacilli (GNB). Molecular typing and resistance detection were performed. Risk factors for colonization with an MDR organism were determined using a nested case-control study.

RESULTS

Consent was obtained from 115 (85%) of 136 eligible participants. Forty-one (36%) residents carried at least one type of MDR organism. The prevalence was 16% MRSA (n = 18), 6% VRE (n = 7) and 21% MDR GNB [n = 24; including extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (n = 12) and Acinetobacter baumannii (n = 6)]. The majority of ESBL-producing E. coli and A. baumannii were clonal. Current wound management [adjusted OR (AOR) 8.81 (95% CI 2.78-27.94), P < 0.001], medical device in situ [AOR 5.58 (95% CI 1.34-23.32), P = 0.018] and pressure ulcer [AOR 3.69 (95% CI 1.06-12.86), P = 0.04] were independent risk factors for MDR organism colonization. Advanced dementia [AOR 3.54 (95% CI 1.23-10.23), P = 0.02] and prolonged antibiotic use [AOR 2.95 (95% CI 1.01-8.60), P = 0.047] were independently associated with MRSA colonization, whilst current wound management [AOR 15.59 (95% CI 4.85-50.10), P < 0.001] and fluoroquinolone use [AOR 4.27 (95% CI 1.20-15.25), P = 0.025] were risk factors for MDR GNB colonization.

CONCLUSIONS

LTCFs are an important reservoir of MDR organisms, with person-to-person transmissions being a potential issue. We have identified several predictors of colonization with MDR organisms, allowing a more targeted management of high-risk residents.

Antimicrobial resistance and stewardship in long-term care settings

Infections and antimicrobial resistance (AMR) in long-term care facilities (LTCFs) are a public health challenge and a future infectious disease threat. More and more data show the dimension and impact of AMR and of inappropriate use of antimicrobials in this setting. Recently, the spread of carbapenemase-producing Enterobacteriaceae has provided new insights into the dangerous role the long-term care sector may play in the AMR problem in a community. Implementation of effective infection and surveillance control programs in LTCFs is challenging, due to scarce resources (personnel, expertise, diagnostic and supportive services), and no or poor coordination of medical care. However, interventions in LTCFs have been proven to be effective: inappropriate use of antibiotics for asymptomatic bacteriuria may be reduced; hand hygiene compliance may be improved; and the transmission of multidrug-resistant organisms may be halted. This paper reviews the most recent epidemiological information on this issue, providing references to valuable intervention programs.

Reducing inappropriate antibiotic prescribing in the residential care setting: current perspectives

Residential aged care facilities are increasingly identified as having a high burden of infection, resulting in subsequent antibiotic use, compounded by the complexity of patient demographics and medical care. Of particular concern is the recent emergence of multidrug-resistant organisms among this vulnerable population. Accordingly, antimicrobial stewardship (AMS) programs have started to be introduced into the residential aged care facilities setting to promote judicious antimicrobial use. However, to successfully implement AMS programs, there are unique challenges pertaining to this resource-limited setting that need to be addressed. In this review, we summarize the epidemiology of infections in this population and review studies that explore antibiotic use and prescribing patterns. Specific attention is paid to issues relating to inappropriate or suboptimal antibiotic prescribing to guide future AMS interventions.

Changes in colonization of residents and staff of a long-term care facility and an adjacent acute-care hospital geriatric unit by multidrug-resistant bacteria over a four-year period

BACKGROUND

In 2012 we undertook a screening study for Enterobacteriaceae with extended-spectrum β-lactamases (ESBLs), derepressed or acquired high-level AmpC cephalosporinases, and metallo-β-lactamases (MBLs), and also methicillin-resistant Staphylococcus aureus (MRSA), in a long-term care facility (LTCF1) and the associated acute care hospital geriatric ward in Bolzano, northern Italy. The study followed up an initial survey carried out in LTCF1 in 2008. For comparison, screening in 2012 was extended to a second LTCF.

METHODS

Urine samples and rectal, inguinal, oropharyngeal, and nasal swabs were plated on selective agars. Isolates were typed by pulsed-field gel electrophoresis. Resistance genes and Escherichia coli belonging to ST131 were sought by PCR. Demographic data were collected.

RESULTS

Fewer residents of LTCF1 were colonized with multidrug-resistant (MDR) bacteria in 2012: all MDR organisms, 53.8% vs 74.8% in 2008; ESBL producers, 49.0% vs 64.0% in 2008; MRSA, 13.2% vs 38.7% in 2008; only 2 MBL-producers were isolated in 2012 vs 8 in 2008. Colonization of staff in LTCF1 by MDR bacteria had also decreased (overall 10.5% in 2012 vs 27.5% in 2008). Changed case mixes and risk factors, together with strengthened hygiene measures probably underlie the changes. Colonization proportions in 2012 in LTCF2 were similar to those in LTCF1. By contrast there was no significant change in the proportion of patients colonized by MDR bacteria in the geriatric ward (22.2% in 2008 vs 22.7% in 2012).

CONCLUSIONS

A significant decrease in the proportions of staff and residents of an LTCF colonized by MDR bacteria was observed over a 4-y interval.

Predictors of methicillin-resistant Staphylococcus aureus colonization at hospital admission

BACKGROUND

The best strategy for active surveillance for methicillin-resistant Staphylococcus aureus (MRSA) remains unclear. We attempted to identify a risk factor score to predict MRSA colonization at hospital admission.

METHODS

Data on 9 variables reported as risk factors for MRSA colonization were analyzed, and a risk factor score to predict MRSA colonization was generated using multivariable logistic regression and receiver operating characteristic curve analyses. This risk score was then prospectively validated.

RESULTS

Four risk factors (nursing home residence, diabetes, hospitalization in the past year, and chronic skin condition/infection) were significantly associated with MRSA colonization (c-statistic = 0.846). A cut-off score of 8 or greater would result in screening 20% of admissions and would detect 71% of MRSA-colonized patients. In the prospective validation study, a cut-off score of 8 or greater required screening 21% of admissions and detected 54% of MRSA. Nursing home residence was the best predictor of MRSA colonization.

CONCLUSION

A similar risk factor-based screening strategy could be used to predict MRSA colonization in other institutions. Our data support routine screening of nursing home patients at hospital admission.

Transmission of methicillin-resistant Staphylococcus aureus in the long term care facilities in Hong Kong

Background

The relative contribution of long term care facilities (LTCFs) and hospitals in the transmission of methicillin-resistant Staphylococcus aureus (MRSA) is unknown.

Methods

Concurrent MRSA screening and spa type analysis was performed in LTCFs and their network hospitals to estimate the rate of MRSA acquisition among residents during their stay in LTCFs and hospitals, by colonization pressure and MRSA transmission calculations.

Results

In 40 LTCFs, 436 (21.6%) of 2020 residents were identified as ‘MRSA-positive’. The incidence of MRSA transmission per 1000-colonization-days among the residents during their stay in LTCFs and hospitals were 309 and 113 respectively, while the colonization pressure in LTCFs and hospitals were 210 and 185 per 1000-patient-days respectively. MRSA spa type t1081 was the most commonly isolated linage in both LTCF residents (76/121, 62.8%) and hospitalized patients (51/87, 58.6%), while type t4677 was significantly associated with LTCF residents (24/121, 19.8%) compared with hospitalized patients (3/87, 3.4%) (p < 0.001). This suggested continuous transmission of MRSA t4677 among LTCF residents. Also, an inverse linear relationship between MRSA prevalence in LTCFs and the average living area per LTCF resident was observed (Pearson correlation −0.443, p = 0.004), with the odds of patients acquiring MRSA reduced by a factor of 0.90 for each 10 square feet increase in living area.

Conclusions

Our data suggest that MRSA transmission was more serious in LTCFs than in hospitals. Infection control should be focused on LTCFs in order to reduce the burden of MRSA carriers in healthcare settings.

Staphylococcus colonization, mortality and morbidity in hemodialysis patients: 10 years of observation

Colonization with Staphylococci is widely distributed among patients with end-stage renal disease who are receiving hemodialysis (HD). In addition to more intensive care and use of artificial devices, the incidence of methicillin-resistant Staphylococcus aureus (MRSA) colonization and infection has increased. Such colonization has recently been associated with a more than doubled mortality rate in HD patients. However, it is not clear whether the (presumably increasing) incidence of methicillin-sensitive Staphylococcus aureus (MSSA) colonization is associated with MRSA and/or morbidity and mortality. We therefore established a screening program in our HD population (n=156) and followed these patients over 10 years. We discovered eighty-eight MSSA-colonized patients and one MRSA-colonized patient by cross-sectional and admission-related screenings between 2000 and 2010. The morbidity and mortality of the HD patients was not related to MSSA colonization. The MSSA colonization rate decreased slightly during the 10-year observation period. We conclude that the incidence of MRSA colonization in our unit was lower compared to that reported in the literature. The reasons for this finding are complex and require further investigation. The incidence of MSSA colonization was frequent but did not impact morbidity or mortality.

A multilevel model of methicillin-resistant Staphylococcus aureus acquisition within the hierarchy of an Australian tertiary hospital

Hospitals without universal single room accommodations typically contain multibed cubicles within wards. In this study, we examined whether the variation in a patient's risk for acquiring methicillin-resistant Staphylococcus aureus (MRSA) in a major tertiary hospital was greatest at the bed, cubicle, or ward level, and quantified the risk of MRSA acquisition associated with exposure to MRSA-colonized/infected patients within the same bed, cubicle, and ward at differently distributed lag times. Nested tri-level hierarchical logistic regression models with random effects were used for non-multiresistant MRSA (nmMRSA) and multiresistant MRSA (mMRSA). The models were internally validated. Receiver operating characteristic curves were used to compare the models' predictive capability The odds of new nmMRSA acquisition were 6.06-fold (95% credible intervals [CrI], 3.93- to 9.34-fold) greater in bed-weeks when a nmMRSA-colonized/infected patient was in the same cubicle 2 weeks earlier. The odds of mMRSA acquisition were 5.12-fold (95% CrI, 4.02- to 6.51-fold) greater in bed-weeks when a colonized/infected patient was in the same ward 2 weeks earlier. The between-cluster variance was highest at the ward level. Patients were at greater risk if there was a colonized/infected patient in the same cubicle or ward 2 weeks earlier. Our findings indicate that focusing on the relevant cubicles and wards during this high-risk period can help target infection control resources more efficiently.

Prevalence, risk factors and molecular epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) colonization in residents of long-term care facilities in Luxembourg, 2010

A prevalence survey of methicillin-resistant Staphylococcus aureus (MRSA) was performed in 2010 in 19 long-term care facilities in Luxembourg. Of the 954 participating residents, 69 (7·2%) were colonized by MRSA. Previous history of MRSA [odds ratio (OR) 7·20, 95% confidence interval (CI) 3·19-16·27], quinolone therapy in the previous year (OR 2·27, 95% CI 1·17-4·41) and ≥24 h care administered per week (OR 4·29, 95% CI 1·18-15·56) were independent risk factors for MRSA colonization. More than 75% of strains were of clonal complex (CC)5, mainly spa-type t003 or sequence type (ST)225 and ST710, which is a rapidly emerging lineage prevalent in central Europe. Five residents were colonized by livestock-associated genotypes belonging to CC398. Previously dominant CC8 strains have recently been replaced by more resistant CC5 strains in Luxembourg.

Antibiotic use and resistance in long term care facilities

INTRODUCTION

The common occurrence of infectious diseases in nursing homes and residential care facilities may result in substantial antibiotic use, and consequently antibiotic resistance. Focusing on these settings, this article aims to provide a comprehensive overview of the literature available on antibiotic use, antibiotic resistance, and strategies to reduce antibiotic resistance.

METHODS

Relevant literature was identified by conducting a systematic search in the MEDLINE and EMBASE databases. Additional articles were identified by reviewing the reference lists of included articles, by searching Google Scholar, and by searching Web sites of relevant organizations.

RESULTS

A total of 156 articles were included in the review. Antibiotic use in long term care facilities is common; reported annual prevalence rates range from 47% to 79%. Part of the prescribed antibiotics is potentially inappropriate. The occurrence of antibiotic resistance is substantial in the long term care setting. Risk factors for the acquisition of resistant pathogens include prior antibiotic use, the presence of invasive devices, such as urinary catheters and feeding tubes, lower functional status, and a variety of other resident- and facility-related factors. Infection with antibiotic-resistant pathogens is associated with increased morbidity, mortality, and health care costs. Two general strategies to reduce antibiotic resistance in long term care facilities are the implementation of infection control measures and antibiotic stewardship.

CONCLUSION

The findings of this review call for the conduction of research and the development of policies directed at reducing antibiotic resistance and its subsequent burden for long term care facilities and their residents.

Modeling the spread of methicillin-resistant Staphylococcus aureus in nursing homes for elderly

Methicillin-resistant Staphylococcus aureus (MRSA) is endemic in many hospital settings, including nursing homes. It is an important nosocomial pathogen that causes mortality and an economic burden to patients, hospitals, and the community. The epidemiology of the bacteria in nursing homes is both hospital- and community-like. Transmission occurs via hands of health care workers (HCWs) and direct contacts among residents during social activities. In this work, mathematical modeling in both deterministic and stochastic frameworks is used to study dissemination of MRSA among residents and HCWs, persistence and prevalence of MRSA in a population, and possible means of controlling the spread of this pathogen in nursing homes. The model predicts that: (i) without strict screening and decolonization of colonized individuals at admission, MRSA may persist; (ii) decolonization of colonized residents, improving hand hygiene in both residents and HCWs, reducing the duration of contamination of HCWs, and decreasing the resident∶staff ratio are possible control strategies; (iii) the mean time that a resident remains susceptible since admission may be prolonged by screening and decolonization treatment in colonized individuals; (iv) in the stochastic framework, the total number of colonized residents varies and may increase when the admission of colonized residents, the duration of colonization, the average number of contacts among residents, or the average number of contacts that each resident requires from HCWs increases; (v) an introduction of a colonized individual into an MRSA-free nursing home has a much higher probability of leading to a major outbreak taking off than an introduction of a contaminated HCW.

MRSA: A Challenge to Norwegian Nursing Home Personnel

In Norway, methicillin-resistant Staphylococcus aureus (MRSA) is increasing in primary healthcare, associated with imported cases and outbreaks in long-term care. According to Norwegian national guidelines, MRSA-exposed healthcare workers (HCWs) and patients are tested. Carriage of MRSA leads to exclusion from work in healthcare institutions. In this study, 388 staff members in 42 nursing homes in Oslo County responded to questions about personal experience with MRSA and of own attitudes to challenges associated with the control and treatment of MRSA patients. Half (52%) of the nursing staff were concerned of becoming infected with MRSA and the consequences of this would be for own social life, family, economy, and work restriction. The concern was associated with risk factors like old buildings not suitable for modern infection control work, low staffing rate (70% without specific training in healthcare and 32% without formal healthcare education), defective cleaning and decolonization, and lack of formal routines and capacity for isolation of MRSA patients. Since the Norwegian MRSA guideline permits patients with persistent MRSA infections to move freely around in nursing homes, the anxiety of the staff to become infected and excluded from job was real.

Revisiting Methicillin-Resistant Staphylococcus aureus Infections

Within less than 50 years, methicillin-resistant Staphylococcus aureus (MRSA) made a tremendous impact worldwide. It is not limited to medical facilities and healthcare institutions anymore. Indeed since two decades, cases of MRSA infections arising from the community among apparently healthy individuals are increasing. In this paper, I will present a case of community-associated MRSA sepsis followed by a comprehensive review about the history, pathogenesis, epidemiology, clinical presentations, diagnostic modalities, therapeutic options, contributing factors, growing cost and other pertinent elements of this newly evolving epidemic of MRSA infections.

MRSA prevalence in European healthcare settings: a review

BACKGROUND

During the past two decades, methicillin-resistant Staphylococcus aureus (MRSA) has become increasingly common as a source of nosocomial infections. Most studies of MRSA surveillance were performed during outbreaks, so that results are not applicable to settings in which MRSA is endemic. This paper gives an overview of MRSA prevalence in hospitals and other healthcare institutions in non-outbreak situations in Western Europe.

METHODS

A keyword search was conducted in the Medline database (2000 through June 2010). Titles and abstracts were screened to identify studies on MRSA prevalence in patients in non-outbreak situations in European healthcare facilities. Each study was assessed using seven quality criteria (outcome definition, time unit, target population, participants, observer bias, screening procedure, swabbing sites) and categorized as 'good', 'fair', or 'poor'.

RESULTS

31 observational studies were included in the review. Four of the studies were of good quality. Surveillance screening of MRSA was performed in long-term care (11 studies) and acute care (20 studies). Prevalence rates varied over a wide range, from less than 1% to greater than 20%. Prevalence in the acute care and long-term care settings was comparable. The prevalence of MRSA was expressed in various ways - the percentage of MRSA among patients (range between 1% and 24%), the percentage of MRSA among S. aureus isolates (range between 5% and 54%), and as the prevalence density (range between 0.4 and 4 MRSA cases per 1,000 patient days). The screening policy differed with respect to time points (on admission or during hospital stay), selection criteria (all admissions or patients at high risk for MRSA) and anatomical sampling sites.

CONCLUSIONS

This review underlines the methodological differences between studies of MRSA surveillance. For comparisons between different healthcare settings, surveillance methods and outcome calculations should be standardized.