Colistin-induced structural and biochemical changes in carbapenem-resistant Acinetobacter baumannii isolated from the hospital environment

BACKGROUND

Acinetobacter baumannii is an emerging multidrug-resistant bacterium and is considered as one of the important causes of nosocomial infections.

OBJECTIVES

The main objectives are to determine the drug-resistant pattern of beta-lactamase-producing A. baumannii, colistin-induced structural and biochemical changes.

METHODS

A. baumannii strains were isolated from the restrooms using the selective media, viz., restroom door, restroom floor, washing area, and restroom tap. A total of 120 samples were collected from all four sampling sites. These strains and their drug-resistance patterns were identified. Then carbapenem-resistance was analyzed and the occurrence of the drug-resistant gene (blaOXA-23) was determined. Colistin was applied at various concentrations (20 - 100 µg/mL) and the molecular mechanism of A. baumannii was analysed.

RESULTS

The bacterial population was high on doors (53 ± 2 CFU/mL), followed by restroom tap (19 ± 1 CFU/mL), restroom floor (14 ± 3 CFU/mL), and washing area (3 ± 0 CFU/mL), respectively. A total of 343 A. baumannii strains were isolated from the 120 samples obtained for one year from the restroom. The isolated bacteria showed resistance to selected carbapenems, with 100% isolates being resistant to imipenem, followed by cefotaxime (1.4 ± 0.2% susceptibility). More blaOXA-23 gene carrying strains were isolated from restroom tap(89 ± 2.1%) than other sources. Colistin exhibited bactericidal activity against drug-resistant A. baumannii. Treating A. baumannii strain with 100 µg/mL colistin induced cell membrane roughness in vitro. Scanning Electron Microscopy (SEM) analysis revealed moderate cell shrinkage after treatment with colistin. Bacterial cells treated with hydrogen peroxide or colistin for 30 min induced the production of hydroxyl radicals. The bacterial lysis increased fluorescence and hydroxyl radicals, and released cellular protein and sugars.

CONCLUSIONS

The isolated A. baumannii was resistant to imipenem and showed susceptibility to colistin. Colistin disrupted cell membrane in drug-resistant A. baumannii in vitro. The regular screening for drug-resistance among A. baumannii strains can help monitor the outbreak of A. baumannii and manage control measures.

The physical environment and multi-professional teamwork in three newly built stroke units

PURPOSE

To explore multi-professional teamwork in relation to the physical environment in three newly built or renovated stroke units.

MATERIALS AND METHODS

An observational study was undertaken. The participants were all staff members of a multi-professional team working in the reviewed stroke units. The data were collected using behavioural mapping and semi-structured observations, and they were analysed by content analysis and descriptive statistics.

RESULTS

Out of all the observations in the behavioural mapping, very few were of two or more members from the team together with a patient. None of the included stroke units had a co-location for all the members of the multi-professional team. Three main categories emerged from the analysis of the interviews: (i) the hub of the unit; (ii) the division of places; and (iii) power imbalance. All the categories reflected the teamwork in relation to parts of the physical environment.

CONCLUSION

The design of the physical environment is important for multi-professional teamwork. Emphasis must be placed on better understanding the impact of the physical environment and on incorporating the evidence related to multi-professional teamwork during the design of stroke units.IMPLICATIONS FOR REHABILITATIONUnderstanding the link between the physical environment and effective teamwork can lead to more tailored and supportive design solutions.The design of the physical environment should be considered as a vital part of effective teamwork in stroke units.The physical environment should include shared workstations, allowing team members to meet and communicate face to face.

Background Information: Isolation Routines

The isolation of patients with suspected or documented infections—to not spread to others—has been discussed for hundreds of years. Guidelines are many, methods are different, attitudes show vide variations, routines and procedures are still changing, regulations by law may be absent, and some healthcare professionals may be afraid of adverse outcomes of isolation [1–44]. Microbes that are spread in the environment, on the hands and equipment are invisible. The invisible agent does not call on attention before the infection; clinical disease, hospital infection or nosocomial infection is a factum that can be registered [23, 28, 29, 35–37]. How to stop the transmission is often “to believe and not believe” in infection control.

Surveillance of bacterial colonisation on contact surfaces in different medical wards

This study was conducted to determine the bacterial colonization of some bacterial groups, including extended-spectrum β-lactamase (ESBLs) producers and methicillin-resistant Staphylococcus aureus (MRSA), on surfaces of the equipment and instruments in patient rooms and other workspaces in three different medical wards. The number of microorganisms on swabs was determined with the colony count method on selective microbiological mediums. The aerobic mesophylic microorganisms were found in 73.5 % out of 102 samples, with the average and maximum values of 2.6 × 102 and 4.6 × 103 colony forming units (CFU) 100 cm-2, respectively. Members of the family Enterobacteriaceae, coagulase positive staphylococci, coagulase-negative staphylococci, and enterococci were detected in 23.4, 31.4, 53.2, and 2.9 % of samples, respectively. The differences in bacterial counts on the surfaces of the psychiatric, oncology, and paediatric wards were statistically significant (P<0.001). About 40 % out of 19 isolates from the family Enterobacteriaceae showed multiple resistance to three or more different groups of tested antibiotics, while ESBL was confirmed for only one strain. Staphylococci isolates were mostly resistant to penicillin. MRSA was confirmed in 5.2 % of the tested S. aureus isolates. Greater attention should be paid to cleaning and the appropriate choice of disinfectants, especially in the psychiatric ward. Employees should be informed about the prevention of the spreading of nosocomial infections. Routine application of rapid methods for hygiene control of surfaces is highly recommended.

Can the physical environment itself influence neurological patient activity?

PURPOSE

To evaluate if a changed physical environment following redesign of a hospital ward influenced neurological patient physical and social activity.

METHODS

A "before and after" observational design was used that included 17 acute neurological patients pre-move (median age 77 (IQR 69-85) years Ward A and 20 post-move (median age 70 (IQR 57-81) years Ward B. Observations occurred for 1 day from 08.00-17.00 using Behavioral Mapping of patient physical and social activity, and location of that activity. Staff and ward policies remained unchanged throughout. An Environmental Description Checklist of each ward was also completed.

RESULTS

Behavioral Mapping was conducted pre-/post-move with a total of 801 Ward A and 918 Ward B observations. Environmental Description Checklists showed similarities in design features in both neurological wards with similar numbers of de-centralized nursing stations, however there were more single rooms and varied locations to congregate in Ward B (30% more single-patient rooms and separate allied health therapy room). Patients were alone >60% of time in both wards, although there was more in bed social activity in Ward A and more out of bed social activity in Ward B. There were low amounts of physical activity outside of patient rooms in both wards. Significantly more physical activity occurred in Ward B patient rooms (median = 47%, IQR 14-74%) compared to Ward A (median = 2% IQR 0-14%), Wilcoxon Rank Sum test z = -3.28, p = 0.001.

CONCLUSIONS

Overall, patient social and physical activity was low, with little to no use of communal spaces. However we found more physical activity in patient rooms in the Ward B environment. Given the potential for patient activity to drive brain reorganization and repair, the physical environment should be considered an active factor in neurological rehabilitation and recovery. Implications for Rehabilitation Clinicians should include consideration of the impact of physical environment on physical and social activity of neurological patients when designing therapeutic rehabilitation environments. Despite architectural design intentions patient and social activity opportunities can be limited. Optimal neurological patient neuroplasticity and recovery requires sufficient environmental challenge, however current hospital environments for rehabilitation do not provide this.

The Role of Facility Design in Preventing the Transmission of Healthcare-Associated Infections: Background and Conceptual Framework

OBJECTIVE:

To describe the conceptual framework and methodology used to conduct a comprehensive literature review of current evidence evaluating the role of the built environment in the transmission of healthcare-associated infections.

BACKGROUND:

A multidisciplinary approach to evaluating a vast and diverse dataset requires a conceptual framework to create a common understanding for interpretation. This common understanding is accomplished through the application of a “chain of transmission” model depicting temporal and physical paths of pathogens that cause healthcare-associated infections. The chain of transmission interventions model argues that infection can potentially be reduced by interrupting any of several links in the chain.

TOPICAL HEADINGS:

The key pathogens impacted by the built environment are identified. The chain of transmission and the conceptual framework are described. Opportunities for intervention through the built environment are presented, which in turn guide the subsequent methodology used to conduct the systematic literature review.

CONCLUSIONS:

The chain of transmission interventions model is a multidisciplinary conceptualization of the interaction between pathogens and the built environment, and this model facilitated a systematic literature review of a very large amount of data.

The Role of the Hospital Environment in the Prevention of Healthcare-Associated Infections by Contact Transmission

OBJECTIVE:

This article describes the role of the hospital environment in the spread of pathogens by direct and indirect contact. In addition, the prevention of transmission through interventions involving the built environment is discussed.

BACKGROUND:

The hospital environment can become contaminated with pathogenic microorganisms, some of which can persist for long periods of time. Although contamination is common, the contribution of the hospital environment to the development of healthcare-associated infections remains unclear. In part spurred by the development of newer technologies to enhance environmental cleaning or to prevent contamination, research into the role of the environment in causing healthcare-associated infections has accelerated.

TOPICAL HEADINGS:

A review of the recent literature finds an increasing body of evidence implicating contaminated surfaces in patient care areas in the transmission of pathogens and the development of infections. Single-patient rooms and optimally placed alcohol hand rub dispensers and other design features can mitigate infection risk. Enhanced environmental cleaning including touchless technologies and self-cleaning surfaces can reduce environmental contamination and may prevent infections.

CONCLUSIONS:

The hospital environment contributes to transmission of pathogens in hospitals and to the development of healthcare-associated infections. Newer technologies to prevent environmental contamination or to enhance cleaning are promising although additional studies with the endpoints of reduction of infections are needed before the role of these technologies is known.

Expert Opinions on the Role of Facility Design in the Acquisition and Prevention of Healthcare-Associated Infections

OBJECTIVE:

To assess expert knowledge, perceptions, and experience on the role of the built environment in the acquisition and transmission of healthcare-associated infections (HAIs), facility design decision-making considerations, and strategies for intervention through facility design and technologies.

BACKGROUND:

Healthcare-associated infections pose a serious and costly threat to public health in the United States. A growing evidence base suggests that the built environment can play a role in interrupting the chain of infection.

METHODS:

Semi-structured individual interviews and triads were conducted with 26 experts in hospital administration, architecture, interior design, infection control, and air and water quality. A grounded theory approach was used for interview coding and interpretation.

RESULTS:

Participants characterized the shift in thinking about the relationship between the built environment and HAI transmission as a “progression,” as accountability for infection prevention has expanded beyond clinicians. Organizational leaders aim to make informed design decisions, but this can be challenging due to the paucity of efficacy and return on investment data. Emerging interventions include copper impregnated materials, seamless flooring, and chilled beams.

CONCLUSIONS:

No single intervention is entirely effective in mitigating HAI risk; multiple interventions are needed. In addition to the built environment, human behavior must be considered, as noncompliance can render even the best designs ineffective. Increased multidisciplinary collaboration is needed to improve the application of evidence and experience in healthcare facility design. In the absence of conclusive evidence regarding interventions aimed at reducing HAI transmission, a combination of research data and practical experience should be used to inform design decisions.

The Role of Facility Design in Preventing Healthcare-Associated Infection: Interventions, Conclusions, and Research Needs

OBJECTIVE:

To summarize the findings and provide recommendations based on the multidisciplinary literature review and industry scan, focusing on the links between the built environment and healthcare-associated infections. To propose a research agenda in order to increase informed design decisions and advance the evidence base.

BACKGROUND:

The HAI-Design project explores the research linking a range of design interventions to healthcare-associated infection. The multidisciplinary team evaluated over 3,800 articles and conducted interviews with a range of stakeholders including CEOs, architects, designers, physicians and other healthcare experts, the results of which are featured in this special Supplement as topical papers.

TOPICAL HEADINGS:

The four topical papers describing the role of the built environment in the acquisition of healthcare-associated infections are summarized. The evidence evaluating the strategies for intervention through the built environment is analyzed, and a research agenda is proposed.

CONCLUSIONS:

While the evidence base supporting the efficacy of strategies and technologies continues to grow, there are currently few data that demonstrate a reduction in infection rates. The need for multidisciplinary collaboration and increased efforts to standardize the evaluation of environmental studies are essential to overcome the many challenges and improve the reliability of data