Predictive Risk Factors for Methicillin-Resistant Staphylococcus aureus (MRSA) Colonisation among Adults in Acute Care Settings: A Systematic Review

Using publicly available UK datasets to identify recruitment sites to maximise inclusion of under-served groups: three case studies

Background

There is strong evidence that those recruited into studies are not always representative of the population for whom the research is most relevant. Development of the study design and funding decisions are points in the research process where considerations about inclusion of under-served populations may usefully be made. Current practical guidance focuses on designing and modifying participant recruitment and retention approaches but an area that has not been addressed is recruitment site selection.

Methods

We present case studies of three NIHR funded trials to demonstrate how publicly available UK population datasets can be used to facilitate the identification of under-served communities for inclusion in trials. The trials have different designs, address different needs and demonstrate recruitment planning across Trauma centres, NHS Trusts and special educational settings.We describe our use of national freely available datasets, such as those provided by NHS Digital and the Office for National Statistics, to identify potential recruitment sites with consideration of health status, socio-economic status and ethnicity as well as clinical and risk factors to support inclusivity.For all three studies, we produced lists of potential recruitment sites in excess of the number anticipated as necessary to meet the recruitment targets.

Discussion

We reflect on the challenges to our approach and some potential future developments. The datasets used are all free to use but each has their limitations. Agreeing search parameters, acceptable proxies and identifying the appropriate datasets, then cross referencing between datasets takes considerable time and particular expertise. The case studies are trials, but the methods are generalisable for various other study types.

Conclusion

Through these exemplars, we aim to build on the NIHR INCLUDE project, by providing trialists with a much needed practical approach to embedding EDI into trial design at the grant application stage.

Healthcare-Associated Infections in Subjects With Severe Acquired Brain Injury: The Effect of Microbial Colonization on the Functional Outcome. Data From a Multicenter Observational Study

Background: Hospital-acquired infections (HAIs) and microbial colonization are a worldwide serious threat for human health. Neurological patients with infections who undergo rehabilitation have a significantly poor recovery. The effect of microbial colonization on the functional outcome in severe acquired brain injury (sABI) subjects is still unclear. Aim: The aim of this multicenter observational study was to describe the clinical impact of HAIs and colonization on the functional outcome of sABI subjects admitted to inpatient neurorehabilitation. Methods: Patients were assigned to three groups: infected (INF), not infected (noINF), and colonized (COL). The Glasgow Coma Scale (GCS), the Rancho Los Amigos Levels of Cognitive Functioning Scale, Disability Rating Scale, and modified Barthel Index (mBI) assessments were performed both at admission and discharge. Results: Two hundred sixty-five (92 female/173 male) patients were enrolled: 134 were assigned to INF, 63 to COL, and 68 to noINF. In the INF group, 231 culture specimens were found positive for bloodstream (44.2%), respiratory tract (25.5%), urinary tract (18.6%), gastrointestinal tract (8.3%), skin (3%), and cerebrospinal fluid (0.4%) infections. After rehabilitation, all groups showed a significant improvement in all assessment tests, except for the noINF group that did not show any improvement in GCS. Both noINF and COL groups showed a significantly higher gain in mBI than the INF group (p = 0.000). The COL group showed a significantly higher gain than the noINF group in GCS (p = 0.001). A significantly lower improvement was detected in the INF group than the COL and noINF groups. The rate of patients who needed functional isolation was higher in the INF group than the COL group. Length of stay (LOS) (in days) was 56 ± 50.7, 88.3 ± 55, and 101.3 ± 73.6 for noINF, INF, and COL groups, respectively. The number of deaths in the INF group was significantly higher (24.6%) than the noINF group (7.4%) (p = 0.005) and comparable to the COL group (19%). Conclusion: Colonized sABI patients obtained a similar functional outcome to that of subjects who had no infections, even if they needed a significantly higher LOS.

One Health in hospitals: how understanding the dynamics of people, animals, and the hospital built-environment can be used to better inform interventions for antimicrobial-resistant gram-positive infections

Despite improvements in hospital infection prevention and control, healthcare associated infections (HAIs) remain a challenge with significant patient morbidity, mortality, and cost for the healthcare system. In this review, we use a One Health framework (human, animal, and environmental health) to explain the epidemiology, demonstrate key knowledge gaps in infection prevention policy, and explore improvements to control Gram-positive pathogens in the healthcare environment. We discuss patient and healthcare worker interactions with the hospital environment that can lead to transmission of the most common Gram-positive hospital pathogens – methicillin-resistant Staphylococcus aureus, Clostridioides (Clostridium) difficile, and vancomycin-resistant Enterococcus – and detail interventions that target these two One Health domains. We discuss the role of animals in the healthcare settings, knowledge gaps regarding their role in pathogen transmission, and the absence of infection risk mitigation strategies targeting animals. We advocate for novel infection prevention and control programs, founded on the pillars of One Health, to reduce Gram-positive hospital-associated pathogen transmission.

Methicillin-resistant Staphylococcus aureus colonization in patients undergoing primary total hip arthroplasty

Introduction. Nasal and skin colonization by methicillin-resistant Staphylococcus aureus (MRSA) are linked to a higher incidence of infection after total joint replacement. The prevalence of colonization is poorly defined in Latin American countries.Aim. The aim of the present study was to determine the prevalence of MRSA colonization in the nostrils and groin using real-time polymerase chain reaction (RT-PCR) in patients undergoing total hip arthroplasty (THA).Methodology. In this cross-sectional study, 146 patients undergoing THA between December 2015 and March 2017 in a tertiary-care university-affiliated hospital in Chile were screened for MRSA colonization before the procedure using RT-PCR independently in the nostrils and groin. Risk factors for colonization were documented.Results. Seven of the 146 (5 %) patients undergoing THA were carriers of MRSA in the nostrils and/or the groin. Recent antibiotic use was identified as a risk factor for colonization, OR=4.86 [95 % confidence interval (CI): 1.56-13.96]. Patients reporting at least one of the seven surveyed risk factors had an OR of 2.39 (95 % CI: 0.37-25.77) for colonization. MRSA colonization frequency was twofold higher in the groin as opposed to the nostrils (P=0.014).Conclusion. Five percent of the patients undergoing THA were identified as carriers of MRSA. Recent antibiotic use is a relevant risk factor for MRSA colonization in patients undergoing primary total hip arthroplasty.

Methicillin-Resistant Staphylococcus Aureus Carrier Rate in Orthopaedic Trauma Patients: A Prospective Cohort Study

OBJECTIVES

To identify the methicillin-resistant Staphylococcus aureus (MRSA) carrier rate among surgical patients on an orthopaedic trauma service and to determine whether screening is an effective tool for reducing postoperative MRSA infection in this population.

DESIGN

Prospective.

SETTING

Level 1 trauma center.

PATIENTS/PARTICIPANTS

Two hundred forty-eight patients with operatively managed orthopaedic trauma conditions during the study period. Two hundred three patients (82%) had acute orthopaedic trauma injuries. Forty-five patients (18%) underwent surgery for a nonacute orthopaedic trauma condition, including 36 elective procedures and 9 procedures to address infection.

INTERVENTION

MRSA screening protocol, preoperative antibiotics per protocol.

MAIN OUTCOME MEASUREMENTS

MRSA carrier rate, overall infection rate, MRSA infection rate.

RESULTS

Our screening captured 71% (175/248) of operatively treated orthopaedic trauma patients during the study period. The overall MRSA carrier rate was 3.4% (6/175). When separated by group, the acute orthopaedic trauma cohort had an MRSA carrier rate of 1.4% (2/143), and neither MRSA-positive patient developed a surgical site infection. Only one MRSA infection occurred in the acute orthopaedic trauma cohort. The nonacute group had a significantly higher MRSA carrier rate of 12.5% (4/32, P = 0.01), and the elective group had the highest MRSA carrier rate of 15.4% (4/26, P < 0.01). The odds ratio of MRSA colonization was 10.1 in the nonacute group (95% confidence interval, 1.87-75.2) and 12.8 for true elective group (95% confidence interval, 2.36-96.5) when compared with the acute orthopaedic trauma cohort.

CONCLUSIONS

There was a low MRSA colonization rate (1.4%) among patients presenting to our institution for acute fracture care. Patients undergoing elective surgery for fracture-related conditions such as nonunion, malunion, revision surgery, or implant removal have a significantly higher MRSA carrier rate (15.4%) and therefore may benefit from MRSA screening. Our results do not support routine vancomycin administration for orthopaedic trauma patients whose MRSA status is not known at the time of surgery.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Bacterial Colonization in COPD Patients Admitted to a Rehabilitation Respiratory Unit and Impact on Length of Stay: A Real-Life Study

Bacterial colonization is a well-known phenomenon in acute care, but scant information is available regarding the rehabilitation setting. We retrospectively analyzed, in COPD patients admitted to a Respiratory Rehabilitative unit in 2010, the number of cultures requested, of positive cultures, and of cultures showing multiple drug resistant (MDR) organisms. We also compared hospital admissions (HA) with versus without positive cultures and with versus without MDR and investigated which baseline variables may predict length of stay (LOS) > 30 days. Of 286 COPD admissions (involving 269 patients, age 71 ± 11 years, males 66%), culture samples were requested in 62 (22%). The rate of colonization and of MDR organisms was 61 and 39%, respectively. Patients with a positive culture had a worse clinical condition and disability, and were more frequently tracheostomized, on invasive mechanical ventilation (MV) and admitted from/discharged to acute care. Patients with MDR cultures showed a lower exercise tolerance. Factors predicting LOS > 30 days were the presence of comorbidities, invasive MV, age > 65 years, and lower functional status, but not a positive culture or MDR presence. To our knowledge, this is the first real-life Italian study investigating the epidemiology of colonization and the association between colonization and LOS in a respiratory rehabilitation setting. Further investigation is necessary to clarify the relationship between colonization burden and patients' baseline clinical status and outcomes.

Enhanced topical delivery of non-complexed molecular iodine for Methicillin-resistant Staphylococcus aureus decolonization

Staphylococcus aureus, a leading cause of serious human infections in both healthcare and community settings, is increasingly difficult to control due to expanding resistance to multiple antibiotic classes. Methicillin-resistant S. aureus (MRSA) strains have disseminated on a global scale and are associated with adverse patient outcomes, increased hospital stays, and significant economic costs to the healthcare system. A proximal step in S. aureus infection is colonization of the nasal mucosa, and effective strategies to decolonize high risk patients to reduce the risk of invasive infection and nosocomial spread represent an important clinical priority. With rising resistance to mupirocin, the most common antibiotic utilized for nasal MRSA decontamination, we are examining the use of pure molecular iodine (I₂)-based formulations for this indication. Recently, an iodophor formulation of povidone-iodine (PVP-I) has shown significant promise for nasal MRSA decontamination by swabbing the anterior nares of patients in hospital settings, but the I₂ concentration in this treatment is less than 0.01% of total iodine species present and like all providone-iodine formulations causes skin staining. Here we determine that a novel non-staining formulation of I₂ combined with the safe organic emollient glycerin delivers high local concentrations of the active antimicrobial entity (I₂) with minimal evaporative loss, exhibits activity at ∼1 part per million against MRSA and other important Gram-positive and -negative human pathogens. This formulation for I₂ topical delivery produced similar reductions in mean bacterial burden and was associated with fewer treatment failures (<2-logfold reduction) than PVP-I in a murine model of MRSA nasal decontamination. Formulations of I₂ in glycerin emollient merit further exploration as topical disinfectants for human medical indications.