Oral Microbes in Hospital-Acquired Pneumonia: Practice and Research Implications

Oral care practices and hospital-acquired pneumonia prevention: A national survey of Australian nurses

BACKGROUND

Hospital-acquired pneumonia (HAP) also known as non-ventilator associated pneumonia, is one of the most common infections acquired in hospitalised patients. Improving oral hygiene appears to reduce the incidence of HAP. This study aimed to describe current practices, barriers and facilitators, knowledge and educational preferences of registered nurses performing oral health care in the Australian hospital setting, with a focus on the prevention of HAP. We present this as a short research report.

METHODS

We undertook a cross sectional online anonymous survey of Australian registered nurses. Participants were recruited via electronic distribution through existing professional networks and social media. The survey used was modified from an existing survey on oral care practice.

RESULTS

The survey was completed by 179 participants. Hand hygiene was considered a very important strategy to prevent pneumonia (n = 90, 58%), while 45% (n = 71) felt that oral care was very important. The most highly reported barriers for providing oral care included: an uncooperative patient; inadequate staffing; and a lack of oral hygiene requisite. Patients' reminders, prompts and the provision of toothbrushes were common ways believed to help facilitate improvements in oral care.

CONCLUSION

Findings from this survey will be used in conjunction with consumer feedback, to help inform a planned multi-centre randomised trial, the Hospital Acquired Pneumonia PrEveNtion (HAPPEN) study, aimed at reducing the incidence of HAP. Findings may also be useful for informing studies and quality improvement initiatives aimed at improving oral care to reduce the incidence of HAP.

Oral and rectal colonization of methicillin-resistant Staphylococcus aureus in long-term care facility residents and their association with clinical status

Staphylococcus aureus is a commensal bacterium in humans, but it sometimes causes opportunistic infectious diseases such as suppurative skin disease, pneumonia, and enteritis. Therefore, it is important to determine the prevalence of S. aureus and methicillin-resistant S. aureus (MRSA) in individuals, especially older adults. In this study, we investigated the prevalence of S. aureus and MRSA in the oral cavity and feces of residents in long-term care facilities (LTCFs). S. aureus was isolated from the oral cavity of 61/178 (34.3%) participants, including 28 MRSA-positive participants (15.7%), and from the feces of 35/127 (27.6%) participants, including 16 MRSA-positive participants (12.6%). S. aureus and MRSA were isolated from both sites in 19/127 individuals (15.0%) and 10/127 individuals (7.9%), respectively. Among 19 participants with S. aureus isolation from both sites, 17 participants showed the same sequence type (ST) type. Then, we analyzed the correlation of S. aureus and MRSA in the oral cavity and rectum with the participant's condition. S. aureus and MRSA positivity in the oral cavity was significantly related to tube feeding, while there was no correlation of rectal S. aureus/MRSA with any factors. Our findings regarding the oral inhabitation of MRSA and its risk factors indicate the importance of considering countermeasures against MRSA infection in LTCFs.

Efficacy of Ceragenins in Controlling the Growth of Oral Microorganisms: Implications for Oral Hygiene Management

Ensuring proper dental hygiene is of paramount importance for individuals' general well-being, particularly for patients receiving medical care. There is a prevailing utilization of conventional oral hygiene items, including toothbrushes and mouthwashes, which have gained widespread acceptance; nevertheless, their limitations encourage investigating novel options in this domain. Our study indicates that ceragenins (CSAs) being lipid analogs of host defense peptides, well-recognized for their wide-ranging antimicrobial properties, may be a potentially efficacious means to augment oral hygiene in hospitalized individuals. We demonstrate that ceragenins CSA-13, CSA-44, and CSA-131 as well as undescribed to date CSA-255 display potent antimicrobial activities against isolates of fungi, aerobic, and anaerobic bacteria from Candida, Streptococcus, Enterococcus, and Bacteroides species, which are well-recognized representatives of microbes found in the oral cavity. These effects were further confirmed against mono- and dual-species fungal and bacterial biofilms. While the ceragenins showed similar or slightly diminished efficacy compared to commercially available mouthwashes, they demonstrated a highly favorable toxicity profile toward host cells, that may translate into better maintenance of host mucosal membrane stability. This suggests that incorporating ceragenins into oral hygiene products could be a valuable strategy for reducing the risk of both oral cavity-localized and secondary systemic infections and for improving the overall health outcomes of individuals receiving medical treatment.

Computer-aided drug repurposing to tackle antibiotic resistance based on topological data analysis

The progressive emergence of antimicrobial resistance has become a global health problem in need of rapid solution. Research into new antimicrobial drugs is imperative. Drug repositioning, together with computational mathematical prediction models, could be a fast and efficient method of searching for new antibiotics. The aim of this study was to identify compounds with potential antimicrobial capacity against Escherichia coli from US Food and Drug Administration-approved drugs, and the similarity between known drug targets and E. coli proteins using a topological structure-activity data analysis model. This model has been shown to identify molecules with known antibiotic capacity, such as carbapenems and cephalosporins, as well as new molecules that could act as antimicrobials. Topological similarities were also found between E. coli proteins and proteins from different bacterial species such as Mycobacterium tuberculosis, Pseudomonas aeruginosa and Salmonella Typhimurium, which could imply that the selected molecules have a broader spectrum than expected. These molecules include antitumor drugs, antihistamines, lipid-lowering agents, hypoglycemic agents, antidepressants, nucleotides, and nucleosides, among others. The results presented in this study prove the ability of computational mathematical prediction models to predict molecules with potential antimicrobial capacity and/or possible new pharmacological targets of interest in the design of new antibiotics and in the better understanding of antimicrobial resistance.

Changes and Clinical Value of Serum miR-24 and miR-223 Levels in Patients with Severe Pneumonia

Introduction

Severe pneumonia progresses rapidly, so early assessment of the severity and prognosis is crucial for reducing mortality rates.

Objective

We explore the role of serum microRNA-24 (miR-24) and microRNA-223 (miR-223) in the prognosis of severe pneumonia.

Methods

There were a total of 96 patients with general pneumonia, 94 patients with severe pneumonia, and 93 healthy people, who were enrolled in this study. The levels of serum miR-24 and miR-223 were detected by real-time fluorescent quantitative PCR in all groups.

Results

The serum miR-223 level in the severe group was higher than that in the common group and the control group, and the miR-24 level was lower than that in the common group and the control group (P<0.05). The serum miR-223 levels and APACHEII scores in the death group were higher than those in the survival group on the first, third, and seventh day after admission, while the miR-24 levels were lower than those in the survival group (P<0.05). The proportion of patients with mechanical ventilation in the death group was higher than that in the survival group (P<0.05). The level of serum miR-24 was negatively correlated with APACHEII score and mechanical ventilation in patients who died of severe pneumonia (P<0.05), and miR-223 was positively correlated with APACHEII score and mechanical ventilation (P<0.05). The AUC predicted by serum miR-24, miR-223, and APACHEII scores alone and jointly were 0.867, 0.839, 0.791, and 0.952, respectively. MiR-24 and miR-223 are protective and independent risk factors for mortality in severe pneumonia patients, respectively (P<0.05). MiR-24 was a protective factor affecting the death of patients with severe pneumonia, and miR-223 was an independent risk factor affecting the death of patients with severe pneumonia (P<0.05).

Conclusion

The combination of serum miR-24 and miR-223 levels on the first day after admission and APACHEII score can effectively predict prognosis.

Best Practices in Oral Care

Topic

Assessing functional cognition is a critical need for intensive care unit survivors transitioning to another level of care.

Clinical Relevance

Up to 62% of patients discharged from an intensive care unit have significant cognitive impairment that is not associated with severity of illness, number of comorbidities, or length of hospital stay. For more than 20 years, researchers have published an array of potentially effective interventions, including case management, patient and informal caregiver education, and home health care services.

Purpose

To describe the impact of and potential interventions for cognitive decline at intensive care unit discharge and discharge readiness on 30-day readmission rates.

Content Covered

Assessing the patient’s functional cognition assessment and advocating for appropriate resources are needed to improve patient and clinical outcomes.

General Factors and Dental-Related Risk Factors for Postoperative Pneumonia or Infectious Complications: A Retrospective Study

Numerous studies report that perioperative oral care decreases the frequency of postoperative pneumonia or infection. However, no studies have analyzed the specific impact of oral infection sources on the postoperative course, and the criteria for preoperative dental care differ among institutions. This study aimed to analyze the factors and dental conditions present in patients with postoperative pneumonia and infection. Our results suggest that general factors related to postoperative pneumonia, including thoracic surgery, sex (male > female), the presence or absence of perioperative oral management, smoking history, and operation time, were identified, but there were no dental-related risk factors associated with it. However, the only general factor related to postoperative infectious complications was operation time, and the only dental-related risk factor was periodontal pocket (4 mm or higher). These results suggest that oral management immediately before surgery is sufficient to prevent postoperative pneumonia, but that moderate periodontal disease must be eliminated to prevent postoperative infectious complication, which requires periodontal treatment not only immediately before surgery, but also on a daily basis.

Multisite Evaluation of Toothbrushes and Microbial Growth in the Hospital Setting

DESIGN

This observational, descriptive study was conducted to determine the prevalence of microbial growth on toothbrushes found in hospital patient rooms.

METHODS

Toothbrush sampling was conducted in 136 acute care hospitals and medical centers from November 2018 through February 2022. Inclusion criteria for the units and patient rooms sampled were as follows: general adult medical-surgical units or critical care units; rooms occupied by adults 18 years or older who were capable of (1) mobilizing to the bathroom; (2) using a standard manual, bristled toothbrush; and (3) room did not have signage indicating isolation procedures.

RESULTS

A total of 5340 patient rooms were surveyed. Of the rooms included, 46% (2455) of patients did not have a toothbrush available or had not used a toothbrush (still in package and/or toothpaste not opened). Of the used toothbrushes collected (n = 1817): 48% (872/1817) had at least 1 organism; 14% (251/1817) of the toothbrushes were positive for 3 or more organisms.

CONCLUSIONS

These results identify the lack of availability of toothbrushes for patients and support the need for hospitals to incorporate a rigorous, consistent, and comprehensive oral care program to address the evident risk of microbe exposure in the oral cavity.

Small extracellular vesicles derived from Nrf2-overexpressing human amniotic mesenchymal stem cells protect against lipopolysaccharide-induced acute lung injury by inhibiting NLRP3

BACKGROUND

Acute lung injury (ALI) is a major cause of respiratory failure in critically ill patients that results in significant morbidity and mortality. Recent studies indicate that cell-based therapies may be beneficial in the treatment of ALI. We recently demonstrated that Nrf2-overexpressing human amniotic mesenchymal stem cells (hAMSCs) reduce lung injury, fibrosis and inflammation in lipopolysaccharide (LPS)-challenged mice. Here we tested whether small extracellular vesicles (sEVs) derived from Nrf2-overexpressing hAMSCs (Nrf2-sEVs) could protect against ALI. sEVs were isolated from hAMSCs that overexpressed (Nrf2-sEVs) or silenced (siNrf2-sEVs) Nrf2. We examined the effects of sEVs treatment on lung inflammation in a mouse model of ALI, where LPS was administered intratracheally to mice, and lung tissues and bronchoalveolar lavage fluid (BALF) were analyzed 24 h later.

METHODS

Histological analysis, immunofluorescence microscopy, western blotting, RT-PCR and ELISA were used to measure the inflammatory response in the lungs and BALF.

RESULTS

We found that sEVs from hAMSCs are protective in ALI and that Nrf2 overexpression promotes protection against lung disease. Nrf2-sEVs significantly reduced lung injury in LPS-challenged mice, which was associated with decreased apoptosis, reduced infiltration of neutrophils and macrophages, and inhibition of pro-inflammatory cytokine expression. We further show that Nrf2-sEVs act by inhibiting the activation of the NLRP3 inflammasome and promoting the polarization of M2 macrophages.

CONCLUSION

Our data show that overexpression of Nrf2 protects against LPS-induced lung injury, and indicate that a novel therapeutic strategy using Nrf2-sEVs may be beneficial against ALI.