A multilocus sequence typing method of Staphylococcus aureus DNAs in a sample from human skin

The skin and mucous membranes are the primary sites of Staphylococcus aureus colonization, particularly those of health care personnel and patients in long-term care centers. We found that S. aureus colonized with a higher abundance ratio on skins which had recovered from pressure injury (PI) than on normal skins in our earlier research on the skin microbiota of bedridden patients. Multilocus sequence typing (MLST) is a useful tool for typing S. aureus isolated from clinical specimens. However, the MLST approach cannot be used in microbiota DNA owing to the contamination from other bacteria species. In this study, we developed a multiplex-nested PCR method to determine S. aureus MLST in samples collected from human skins. The seven pairs of forward and reverse primers were designed in the upstream and downstream regions, which were conserved specifically in S. aureus. The first amplifications of the seven pairs were conducted in a multiplex assay. The samples were diluted and applied to conventional PCR for MLST. We confirmed that the method amplified the seven allele sequences of S. aureus specifically in the presence of untargeted DNAs from human and other skin commensal bacteria. Using this assay, we succeeded in typing sequence types (STs) of S. aureus in the DNA samples derived from the skins healed from PI. Peaks obtained by Sanger sequencing showed that each sample contained one ST, which were mainly categorized into clonal complex 1 (CC1) or CC5. We propose that this culture-free approach may be used in detecting S. aureus in clinical specimens without isolation.

The Relationship between Nursing Practice Environment and Pressure Ulcer Care Quality in Portugal's Long-Term Care Units

BACKGROUND

The morbidity associated with ageing has contributed to an increase in the prevalence of Pressure Ulcers (PUs) in all care settings. The impact of these on people's quality of life and the extent of the associated economic and social burden constitutes today, by their importance, a serious public health problem. This study aims to describe the nursing work environment in Portuguese long-term care (LTC) units and to assess how this environment relates to the quality of PU care.

METHODS

A longitudinal study among inpatients with PUs was conducted in LTC units. The Nursing Work Index-Revised Scale (NWI-R) was sent to all nurses in these units. Cox proportional hazard models were used to relate the satisfaction degree with the service (measured by the NWI-R-PT items) to the healing time of the PUs, adjusting for confounders.

RESULTS

A total of 165 of 451 invited nurses completed the NWI-R-PT. Most were women (74.6%) and had 1 to 5 years of professional experience. Less than half (38.4%) had education in wound care. Of the 88 patients identified with PUs, only 63 had their PU documented, highlighting the difficulties in updating electronic records. The results showed that the level of concordance with Q28 "Floating so that staffing is equalised among units" is strongly associated with a shorter PU healing time.

CONCLUSION

A good distribution of nursing staff over the units will likely improve the quality of wound care. We found no evidence for possible associations with the questions on participation in policy decisions, salary level, or staffing educational development and their relationship with PUs healing times.

Multilayered silicone foam dressings potentially used for preventing recurrence of pressure injuries: A bench-to-clinical bedside study

AIM

This study aimed to evaluate the use of multilayered silicone foam dressings for preventing pressure injury recurrence by reducing friction, pressure, and shear force at skin sites where previous pressure injuries closed.

METHODS

A bench-to-clinical bedside investigation was conducted. In the bench, three multilayered silicone foam dressings were assessed. The simulated skin-shearing test consisted of a weight, a polyurethane-based skin model containing a three-axis tactile sensor, dressings, a table covered with bedsheets, and a mechanical tester. The mechanical tester simultaneously measured the interface friction force and internal shear force and pressure continuously during skin model movements. No-dressing was used as a negative control. In clinical bedside assessments, a multilayered silicone foam dressing with lower friction and shear force was applied to two bedridden patients. Photographs and ultrasound images were used to assess the recurrence of pressure injury.

RESULTS

The dressings significantly reduced friction, pressure, and shear force compared with these parameters in the negative control. No significant differences in the shear forces between the dressings were observed. One clinical case did not develop a new pressure injury reaching the dermis. However, the second case developed a new pressure injury within one month after the first pressure injury closed.

CONCLUSION

Our bench-to-clinical bedside study revealed that multilayered silicone foam dressings can potentially prevent pressure injury recurrence.

Skin hydration measurement and the prediction of the early development of pressure ulcers among at risk adults: A systematic review

This systematic review aimed to examine skin hydration and determine if this biophysical parameter can predict pressure ulcer development in at risk adults. A literature search was conducted in March 2022, using PubMed, CINAHL, SCOPUS, Cochrane, and EMBASE databases. A total of 1727 records were returned, with 9 studies satisfying the inclusion criteria. Data were extracted using a pre-designed extraction tool and a narrative synthesis of the data was undertaken. The methodological quality of the included articles was assessed using the evidence-based librarianship checklist. Included studies were published between 1997 and 2021, with most using a prospective cohort design (88.9%, n = 8). The mean sample size was 74 participants (SD = 38.6; median 71). All studies measured skin hydration objectively, with 55.6% (n = 5) using the Corneometer® CM825 and 33.3% (n = 3) of studies reported a statistically significant association between skin hydration and pressure ulcer development. The mean evidence-based librarianship percentage was 66.6% (SD: 20.7%), however, only 33.3% (n = 3) of studies scored ≥75%, indicating validity. The quality of included studies, methodology variation, and reported results has reduced the homogeneity of outcomes. This review highlights the requirement for future research evidence to ascertain the role of skin hydration in pressure ulcer development.

Sampling the skin surface chemistry for diagnosis and prognosis

Skin and wound blotting are non‐invasive techniques used to sample the skin and wound surface chemistry, whereby a nitrocellulose membrane is applied to an intact or broken cutaneous surface to detect biomarkers. However, there has been no comprehensive review of the evidence for the techniques used and data obtained to date. The primary aim of this study was to review the utilities of surface blotting for the diagnosis and prognosis of physiological, pre‐disease, and pathological states. The secondary aim was to summarise the procedural steps. A systematic literature search was conducted on 9 July 2021 using Medline, Embase, and Google Scholar databases. Investigators used McMaster's Critical Review Form for Quantitative Studies to assess quality, then performed a narrative synthesis reporting according to Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) guidelines. Twenty‐five studies were reviewed. Eighteen studies were of good quality, and seven were of moderate quality. These studies conducted skin and wound blotting on 176 animals and 1546 humans. Studies reported physiological and pathological states for diagnosis and prediction of conditions, including skin tears, wound healing, biofilm detection, and skin barrier function. The four steps for blotting are surface preparation, blot preparation, application and removal of blot, and analysis. This review demonstrates that blotting can determine the skin and wound surface chemistry using a versatile and reproducible technique. However, future research is needed to validate the technique and skin biomarkers identified.

Interspecies Regulation Between Staphylococcus caprae and Staphylococcus aureus Colonized on Healed Skin After Injury

Staphylococcus spp. colonize commensally on the human skin. Some commensal coagulase-negative staphylococci and Staphylococcus aureus are also involved in nosocomial infections. Bacteria were collected from skin healed from pressure injury (PI). After the collection time points, some patients suffered from recurrent PI (RPI). This study analyzed the characteristics of Staphylococcus spp. on healed skin before recurrence between healed skin that suffered from RPI within 6 weeks (RPI group) and healed skin that did not suffer within the duration (non-RPI group) by Staphylococcus spp.-specific sequencing. Of the seven patients in the RPI group, two were dominated by S. aureus and four by Staphylococcus caprae, coagulase-negative human commensal staphylococci in the RPI group. Using mouse models, both S. caprae and S. aureus, but not Staphylococcus epidermidis, colonized on skin healed from injury at significantly higher rates than normal skin. Although subcutaneous injection of S. caprae did not induce lesion formation, the bacterium exhibited high hemolytic activity on human red blood cells. Lesion formation by subcutaneous injection of S. aureus was significantly suppressed in the presence of S. caprae. The hemolytic activity of rabbit blood cells of S. aureus was suppressed by S. caprae, whereas the hemolytic activity of S. caprae was dramatically suppressed by S. aureus. Data indicated that each of the two Staphylococcus spp. suppresses the pathogenicity of the other and that the imbalance between the two is associated with RPI.

The panniculus carnosus muscle: a missing link in the chronicity of heel pressure ulcers?

Chronic and recurring pressure ulcers (PUs) create an unmet need for predictive biomarkers. In this work, we examine the panniculus carnosus, a thin cutaneous muscle, traditionally considered vestigial in humans, and ask whether the panniculus may play a role in the chronicity and reinjury of heel PUs. To determine whether humans have a panniculus muscle layer at the heel, we dissected eight cadavers. To assess the influence of the panniculus layer on PU, we performed computational simulations of supine weight bearing. Finally, we assessed panniculus regeneration in fluorescent mice. Results show a panniculus layer present in all cadavers examined. Simulations show a thin layer of panniculus muscle causes a dramatic decrease in the volume of soft tissue experiencing high strain and stress, compared to a heel without a panniculus. Importantly, in the mouse model, the panniculus fails to regenerate after PU, even when other cutaneous layers had fully regenerated. Our work shows that the panniculus is able to redistribute load around the heel bone, which might allow it to prevent PUs. Moreover, it is highly susceptible to incomplete regeneration after PU. Poor panniculus regeneration after PU might be a predictive anatomical biomarker for recurrence, and this biomarker should be evaluated prospectively in future clinical trials.

Increased temperature at the healed area detected by thermography predicts recurrent pressure ulcers

Preventing recurrent pressure ulcers is an important challenge in healthcare. One of the reasons for the high rate of recurrent pressure ulcers is the lack of assessment methods for their early detection. Therefore, this study aimed to determine the thermographic characteristics of the healed area and to consider the predictive validity of thermographic images for recurrent pressure ulcers within a 2-week period. This observational study was conducted at a long-term care facility in Japan between July 2017 and February 2019 among patients whose pressure ulcers had healed. Thermographic images of the healed area were recorded once a week until recurrence or until the end of the study. We enrolled 30 participants, among whom 8 developed recurrent pressure ulcers. The generalised estimation equation revealed that the thermographic finding of increased temperature at the healed area compared to that of the surrounding skin was significantly associated with recurrent pressure ulcers (odds ratio: 101.13, 95% confidence interval: 3.60-2840.77, p = .007); the sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio and negative likelihood ratio for recurrent pressure ulcers within 2 weeks were 0.80, 0.94, 0.62, 0.97, 12.9 and 0.2, respectively. Our thermographic findings revealed that the temperature of the healed area was higher than that of the surrounding skin; this could be a useful predictor of pressure ulcer recurrence within 2 weeks, even in the absence of macroscopic changes.

LimpiAD foam and the potential control of the pressure ulcers onset

Pressure ulcers development is an undesirable event that often worsens the clinical condition of patients already affected by severe pathologies. Since the aetiology of this clinical complication is unclear yet, at current the primary approach to treat the problem is the adoption of suitable patients' assistance procedures. At the same time, the research focuses on finding medicaments or treatment strategies that could prevent the lesions and/or accelerate their healing. The international market's wide range of cosmetic/pharmaceuticals products is mainly topical preparations based on emollient agents to preserve or restore skin homeostasis. On the other hand, the skin microbiome's implication in the pressure ulcers occurrence is mainly unknown. Based on these assumptions, here we tested an innovative preparation, the LimpiAD foam, as a potential preventive strategy of pressure ulcers onset. The active component of this product is composed of hyaluronic acid conjugated with a bacterial cell wall fragment of C. acnes DSM 28251. For LimpiAD foam, we hypothesised a combined action of the two components on the skin tissue, an emollient effect due to the hyaluronic acid properties together with a modulatory effect on the skin microbiota carried out by the component of bacterial derivation. Our results supported the hypothesis and suggested a potential role of LimpiAD foam in pressure ulcers prevention.

Association of Skin Microbiome with the Onset and Recurrence of Pressure Injury in Bedridden Elderly People

Pressure injuries have been identified as one of the main health hazards among bedridden elderly people. Bedridden elderly people often stay in the same position for a long time, because they cannot switch positions; thus, the blood flow in the part of the body that is being compressed between the bed and their own weight is continuously blocked. As a result, redness and ulcers occur due to lacking oxygen and nutrients in the skin tissues, and these sites are often infected with microorganisms and, thus, become suppurative wounds, a condition commonly determined as pressure injuries. If left untreated, the pressure injury will recur with microbial infections, often resulting in cellulitis, osteomyelitis, and sepsis. The skin microbiome, in which many types of bacteria coexist, is formed on the skin surface. However, it remains unclear what characteristic of the skin microbiome among the bedridden elderly constitutes the development and severity of pressure injuries and the development of post-pressure injury infections. Thus, in this review article, we outlined the changes in the skin microbiome among the bedridden elderly people and their potential involvement in the onset and recurrence of pressure injuries.

Skin Physiology and its Microbiome as Factors Associated with the Recurrence of Pressure Injuries

BACKGROUND

Preventing recurrent pressure injuries (RPIs) is one of the important challenges faced in healthcare, but the risk factors of RPIs have not been fully revealed. This study aims to explore factors associated with RPIs, by focusing on skin physiology and its microbiome as local factors crucial for the health of healed tissue after pressure injury healing.

METHODS

This prospective observational study was conducted in a long-term care facility in Japan with patients whose PIs had healed within 1 month. Skin physiology was evaluated by stratum corneum (SC) hydration, pH, and transepidermal water loss. Skin bacteria was collected by tape stripping, followed by 16S ribosomal RNA-based metagenomics analysis. These parameters were evaluated every two weeks over a period of six weeks.

RESULTS

A total of 30 patients were included in this study, and 8 patients (26.7%) had an RPI within 6 weeks. In this study, significantly lower SC hydration and a higher rate of Staphylococcus species on the healed site were found in the RPI group.

DISCUSSION

A high rate of RPIs (about one in four) points out the necessity of a further care strategy on the healed PIs. Lower skin hydration and/or the increase in Staphylococcus bacteria may have a potential to be used as a biomarker for the prediction of RPIs, or may be an intervention point for the prevention of RPIs by, for example, skin cleansing with moisturizing care.