Skin Flora Research Articles

The MIC distribution of dalbavancin differs between different coagulase-negative staphylococci.

CoNS constitute a significant part of the human microbiota of skin and mucous membranes. They can cause nosocomial infections, and have shown decreased susceptibility to several antibiotics. The few remaining treatment options include (lipo)glycopeptides such as dalbavancin. However, there is a lack of knowledge concerning whether susceptibility to lipoglycopeptides varies between different species of CoNS. To determine the susceptibility to dalbavancin in different species of CoNS. We investigated 480 bacterial isolates from 10 CoNS species: Staphylococcus epidermidis, Staphylococcus capitis, Staphylococcus caprae, Staphylococcus haemolyticus, Staphylococcus lugdunensis, Staphylococcus warneri, Staphylococcus pettenkoferi, Staphylococcus hominis, Staphylococcus sciuri and Staphylococcus simulans. The isolates were randomly selected from different sources of infection, including blood isolates, as well as deep and superficial infections. Antibiotic susceptibility was tested with the gradient test method. There was a statistically significant difference (ANOVA; P < 0.0001) in the MIC distribution for dalbavancin between different CoNS species. S. sciuri was the least susceptible species, with 90% of the isolates having an MIC value for dalbavancin above the EUCAST breakpoint of 0.125 mg/L. The lowest MIC90 values were seen for S. capitis, S. simulans and S. caprae (all 0.032 mg/L). This study demonstrated a difference in dalbavancin susceptibility between different CoNS species, suggesting that species-specific breakpoints for CoNS should be further investigated.

(020) Does Climate Impact IPP Infection Risk? Assessment of Temperature and Dew Point on IPP Infections

Abstract Introduction Variations in climate have been associated with greater risk of surgical site infections, urinary tract infections, and changes in the skin microbiome. Although the pathogenic organisms for inflatable penile prosthesis (IPP) infections are commonly skin flora, limited data exists on the impact of climate on IPP infections. We sought to evaluate the impact of climate on the pathogenic organisms of IPP infections in a large international, multicenter cohort. Objectives To assess whether the time of the year, during which surgery was performed, affected device infections. Methods We performed a multi-institutional, retrospective study of patients undergoing IPP surgery. We then evaluated whether the month or season, during which surgery was performed, affected device infections. Additionally, we assessed the effect of temperature, dew point, and humidity on the microorganisms involved in implant infections. Infections were classified as Gram positive, Gram negative, or mixed (including a combination of Gram positive, Gram negative, and/or fungi). A univariate logistic regression analysis was undertaken. Results A total of 5289 patients with a mean age of 62.2 ± 10.8 years received IPP placement. A total of 103 (1.9%) infections were recorded. Overall, 38 (36.9%) infections were caused by Gram positive bacteria. An increase in temperature was associated with a higher risk of infection with Gram positive bacteria (OR: 1.03, 95% CI: 1 to 1.07, p = 0.035). No statistically significant differences were recorded in terms of season (p = 0.19) and month (p = 0.29). Conclusion Higher temperature is associated with greater risk of Gram positive infections whereas lower temperature and dew point were associated with a higher risk of mixed infections. These findings may help surgeons tailor antibiotic prophylaxis based on local climate. Disclosure No.

Variations in milk, udder skin, and fecal microbiota and their relationships with blood metabolites and milk composition in dairy cows.

This study examined the milk, udder skin, feces, and bedding microbiota in a dairy farm. Blood metabolites concentration and milk composition were also determined to examine their relationship with variations in the microbiota. Samples were collected from 10 healthy cows during the summers of 2018 and 2020. Milk protein, fat, and solid-not-fat contents were higher, and blood urea nitrogen and nonesterified fatty acid levels were lower in the 2020 samples. Principal coordinate analysis demonstrated that milk, udder skin, and fecal microbiota were separate groups. Year-to-year differences were distinct for milk and udder skin microbiota; however, the fecal microbiota of the 2018 and 2020 samples were similar. The bedding microbiota grouped with the udder skin microbiota of the 2018 samples. Although nonpathogens found as prevalent taxa in udder skin microbiota were likely to be found as abundant taxa in milk microbiota, selection and elimination occurred during transmission. Network analysis suggested that bacterial taxa of milk, udder skin, and fecal microbiota were unrelated to blood metabolites and milk composition, regardless of pathogens or nonpathogens.

Facial Physiological Characteristics and Skin Microbiomes Changes are Associated with Body Mass Index (BMI).

Overweight and obesity have become public health problems worldwide. An increasing number of research works are focusing on skin physiology and the manifestations of obesity-associated skin diseases, but little is known about the correlations between body mass index (BMI), facial skin physiological parameters, and the facial skin microbiome in healthy women. To investigate the correlations between BMI, facial skin physiological parameters and facial bacteria and fungi in 198 women aged 18 to 35 years in Shanghai. According to the international BMI standard and Chinese reference standard, subjects were divided into three groups, "lean" B1, "normal" B2 and "overweight" B3, and the physiological parameters of facial skin were measured by non-invasive instrumental methods, and the skin microbiota was analyzed by 16S rRNA and ITS high-throughput sequencing. Compared with the skin physiological parameters of the normal group, those of the overweight group exhibited a significant increase in trans-epidermal water loss (TEWL), which indicated that the skin barrier was impaired. The skin haemoglobin content was significantly increased, and skin surface pH was significant decreased in those with a high BMI. Furthermore, α-diversity, analysed using the Shannon, Chao, Sobs, and Ace indexes, was increased in the overweight group, suggesting that the diversity and species abundance of facial bacterial and fungal microbiota were also increased. Moreover, the overweight group had higher abundances of Streptococcus, Corynebacterium, Malassezia, and Candida. Notably, skin surface pH was significantly and negatively correlated with the relative abundances of Malassezia, Candida, and Cladosporium. Besides, the abundance of Malassezia was positively associated with the abundances of Staphylococcus and Corynebacterium. These results indicate that BMI is associated with differences in the biophysical properties and microbiome of the facial skin. A high BMI affects the integrity of skin barrier and changes the skin flora diversity and species composition.

Eradication of skin microbiota restores cytokine production and release in polymorphic light eruption.

Polymorphic light eruption (PLE) has been mechanistically linked to cytokine abnormalities. Emerging preclinical evidence posits the skin microbiome as a critical modulator of ultraviolet (UV)-induced cytokine expression, thereby influencing subsequent immune responses. This intricate relationship remains underexplored in the context of PLE. Hence, we investigated the differential responses between disinfected and non-disinfected skin following both single and repetitive exposures to solar-simulated UV radiation in patients with PLE. An experimental, half-body pilot study was conducted involving six PLE patients and 15 healthy controls. Participants' skin was exposed to single and multiple doses of solar-simulated UV radiation, both in disinfected and in non-disinfected skin areas. The co-primary outcomes were PLE score and cytokine expression in blister fluid analysed through OLINK proteomic profiling. Secondary outcomes were erythema, pigmentation, induction of apoptotic cells in vacuum-generated suction blisters, and density of infiltrate in skin biopsies of PLE patients. Among the 71 cytokines analysed, baseline expression levels of 20 specific cytokines-integral to processes such as apoptosis, inflammation, immune cell recruitment, cellular growth, and differentiation-were significantly impaired in PLE patients compared with healthy controls. Notably, skin disinfection reversed the observed cytokine imbalances following a single UV exposure at the minimal erythema dose (MED) level and exhibited even more pronounced effects after multiple UV exposures. However, no significant differences were evident in PLE score, erythema, pigmentation, or rates of apoptotic cell induction upon UV radiation. These findings provide evidence for UV-driven cytokine regulation by the skin microbiota and imply microbiome involvement in the PLE immune response.

Differences in microorganisms causing infection after cranial and spinal surgeries.

The primary aim of this retrospective study was to assess differences in the pathogens causing surgical site infections (SSIs) following craniectomies/craniotomies and open spinal surgery. The secondary aim was to assess differences in rates of SSI among these operative procedures. ANOVA tests with Bonferroni correction and incidence risk ratios (RRs) were used to identify differences in pathogens by surgical site and procedure using retrospective, de-identified records of 19,993 postneurosurgical patients treated between 2007 and 2020. The overall infection rates for craniotomy/craniectomy, laminectomy, and fusion were 2.1%, 1.1%, and 1.5%, respectively, and overall infection rates for cervical, thoracic, and lumbar spine surgery were 0.3%, 1.6%, and 1.9%, respectively. Craniotomy/craniectomy was more likely to result in an SSI than spine surgery (RR 1.8, 95% CI 1.4-2.2, p < 0.0001). Cutibacterium acnes (RR 24.2, 95% CI 7.3-80.0, p < 0.0001); coagulase-negative staphylococci (CoNS) (methicillin-susceptible CoNS: RR 2.9, 95% CI 1.6-5.4, p = 0.0006; methicillin-resistant CoNS: RR 5.6, 95% CI 1.4-22.3, p = 0.02); Klebsiella aerogenes (RR 6.5, 95% CI 1.7-25.1, p = 0.0003); Serratia marcescens (RR 2.4, 95% CI 1.1-7.1, p = 0.01); Enterobacter cloacae (RR 3.1, 95% CI 1.2-8.1, p = 0.02); and Candida albicans (RR 3.9, 95% CI 1.2-12.3, p = 0.02) were more commonly associated with craniotomy/craniectomy cases than fusion or laminectomy SSIs. Pseudomonas aeruginosa was more commonly associated with fusion SSIs than craniotomy SSIs (RR 4.4, 95% CI 1.3-14.8, p = 0.02), whereas Escherichia coli was nonsignificantly associated with fusion SSIs compared to craniotomy SSIs (RR 4.1, 95% CI 0.9-18.1, p = 0.06). Infections with E. coli and P. aeruginosa occurred primarily in the lumbar spine (p = 0.0003 and p = 0.0001, respectively). SSIs due to typical gastrointestinal or genitourinary gram-negative bacteria occur most commonly following lumbar surgery, particularly fusion, and are likely to be due to contamination of the surgical bed with microbial flora in the perianal area and genitourinary tract. Cutibacterium acnes in the skin flora of the head and neck increases risk of infection due to this microbe following surgical interventions in these body sites. The types of gram-negative bacteria associated with craniotomy/craniectomy SSIs suggest potential environmental sources of these pathogens. Based on the authors' findings, neurosurgeons should consider using a two-step skin preparation with benzoyl peroxide, in addition to a standard antiseptic such as alcoholic chlorhexidine for cranial, cervical, and upper thoracic surgeries. Additionally, broader gram-negative bacterial coverage, such as use of a third-generation cephalosporin, should be considered for lumbar/lumbosacral fusion surgical antibiotic prophylaxis.

IL-17A inhibitors alleviate Psoriasis with concomitant restoration of intestinal/skin microbiota homeostasis and altered microbiota function.

Disturbed gut microbiota and associated metabolic dysfunction exist in Psoriasis. Despite the growing use of interleukin-17 inhibitor (anti-IL17) therapy, the effect of anti-IL17 on gut/skin microbiota function is not fully understood in patients with Psoriasis. Therefore, we explored whether Psoriasis is associated with alterations in selected gut/skin microbiota in a study cohort, and a longitudinal cohort study to reveal the effects of IL-17A inhibitor treatment on gut microbiota in Psoriasis. In a case-control study, 14 patients with Psoriasis and 10 age, sex and body mass index-matched Healthy Controls were recruited. Longitudinal mapping of the gut microbiome was performed using 16S rRNA gene sequencing. Mouse models were used to further study and validate the interrelationship between the skin microbiome and the gut microbiome in Psoriasis. PICRUST2 was applied to predict the function of the bacterial community. In Psoriasis patients, gut microbiota dysbiosis was present with increased heterogeneity: decreased Bacteroidota and increased Firmicutes as well as Actinobacteriota predominating in Psoriasis. Escherichia-Shigella enrichment was associated with reduction in serum levels of total bile acid and markers in Apoptotic pathways. After IL-17A inhibitor treatment in Psoriasis patients, longitudinal studies observed a trend toward a normal distribution of the gut microbiome and modulation of apoptosis-related metabolic pathways. Results from a mouse model showed dysregulation of the skin microbiota in Psoriasis characterized by Staphylococcus colonization. The psoriatic gut/skin microbiota exhibits loss of community stability and pathogen enrichment. IL-17A inhibitors restore microbiota homeostasis and metabolic pathways, reduce pro-inflammatory cytokine expression, and alleviate symptoms in patients with Psoriasis.

Longitudinal analysis of the skin microbiome in association with hand eczema, hand hygiene practices and moisturizer use.

The skin microbiota maintains a physical and immunological barrier to the environment. Little is known about how the microbiome changes over time or the effect of hand hygiene practices and moisturizer use. To assess sex-specific changes in skin bacteria over time, and how the microbiome is related to self-reported hand eczema, hand hygiene practices and use of moisturizers. Swab samples from the dorsal hand were collected at baseline and 6.5 years later during the COVID-19 pandemic, in 168 participants from the RHINESSA study in Bergen, Norway. The skin samples were analysed by 16S rRNA amplicon sequencing. The alpha diversity of the hand microbiome increased from baseline to follow-up, and beta diversity differed by sex at both time points. The relative abundance increased for several bacteria from baseline to follow-up, with sex-specific differences. Current hand eczema and aggravating hand eczema during the COVID-19 pandemic were associated with an increase in Staphylococcus. High hand washing frequency at home was associated with lower alpha diversity and with higher abundance of Staphylococcus, Corynebacterium, Finegoldia, and Pseudomonas and lower abundance of Propionibacterium and Pelomonas. The alpha diversity increased with increasing time passing between hand washing and sampling, whereas more frequent moisturizer use was associated with significantly lower alpha diversity, and a change in abundance for some bacteria, such as more Pseudomonas. This longitudinal study revealed an overall increase in skin microbial diversity over a 6-year period, which was unexpected since follow-up was performed during the COVID-19 pandemic when vigorous hand hygienic practices were introduced. Sex-specific differences were identified at both time points. Individuals with hand eczema seem to develop a more dysbiotic skin bacterial community over time. Hand washing and use of moisturizers, with typically gender-specific habitual patterns, may lead to change in bacterial composition.

Skin ulcers and microbiota in Rana dybowskii: Uncovering the role of the gut-skin axis in amphibian health

Amphibians' gut and skin microbiota are vital for host health. Ulcers may affect the skin microbiota, with unknown impacts on the gut microbiota. Skin diseases could influence both, but research on their interrelationships is limited. The cutaneous and gut microbiota of healthy and ulcerated Rana dybowskii were analyzed with Illumina sequencing. The result showed healthy frogs showed greater alpha diversity in skin microbiota than ulcerated ones, with no gut microbiota difference. Bray-Curtis and unweighted UniFrac distances revealed distinct skin microbiotas in healthy versus ulcerated groups and significant gut microbiota differences only in Bray-Curtis. Linear discriminant analysis of effect size (LEfSe) showed that ulcerated skin groups were enriched in Proteobacteria and healthy in Actinobacteria. A variety of analyses revealed that diseased frogs, unlike healthy ones, exhibit similar skin and gut microbiota, suggesting disease impacts microbiota relationships and composition. Using the indicator method, identify key bacterial species indicating healthy or diseased status in the frog's skin and gut microbiota. There were significant differences in skin and gut microbiota functions between diseased and healthy frogs, with disease impacting bacterial community structure and physiological functions. Research on R. dybowskii indicated disease aligns the skin and gut microbiota, affecting composition and function, with distinct bacterial indicators for health and disease status. This research underscores the complex interplay between skin and gut microbiota in amphibian health, highlighting implications for disease understanding and conservation strategies.

Comparative profiling of the skin and gut microbiota during metamorphosis in Chinese spiny frogs (Quasipaa spinosa) highlights microbial communities involved in disease pathogenesis

The symbiotic microbiota inhabiting the skin and gut of amphibians exerts roles in maintaining host health, especially during the critical stage of complete metamorphosis where failure to remodel the microbiota can result in various diseases. However, the composition and alterations in the amphibian microbiota in diverse diseased populations, as well as the exact mechanisms underlying disruptions in skin and gut microbial communities leading to diseases, are not yet well established. Herein, skin and gut microbiota were sampled from healthy Chinese spiny frogs (CTL group) as well as individuals with ascites disease (AD group), cataract disease (CD group), and rotten-skin disease (RD group) for Illumina high-throughput sequencing analysis to comprehensively explore potential associations between microbiota composition and the health status of the host. Venn diagrams and UpSet analysis revealed that the CTL group exhibited the highest number of unique amplicon sequence variants (ASVs) in their skin, while the CD group displayed the lowest abundance of ASVs in their gut. Compared to the CTL group, the alpha-diversity of skin microbiota was dramatically depressed in diseased groups, and notable variations in the beta-diversity of both skin and gut microbiota were observed. Further compositional analysis identified Firmicutes, Proteobacteria, and Bacteroidota as the dominant bacterial phyla in both skin and gut microbiota, although their relative abundances varied widely among groups. The linear discriminant analysis effect size (LEfSe) analysis identified various bacteria species with substantial differences between skin and gut microbiota groups including beneficial populations as well as opportunistic ones. Functional predictions indicated significant differences between CTL and diseased groups mainly enriched in metabolism-relevant pathways. Furthermore, in vitro culture experiments confirmed the presence of a total of 19 strains of bacteria from the skin microbiota of RD group, including opportunistic bacteria population Acinetobacter closely associated with spiny frog rotten-skin disease. Taken together, this work provides insights into the composition dynamics of skin and gut microbiota under different health conditions in spiny frogs, highlighting potential applications for symbiotic microbiota modification in promoting healthy amphibian culture practices as well as preventing diseases.

Extraction of macroalgae phenolic compounds for cosmetic application using eutectic solvents

Cosmetic industry remains a major focus of economic development in the 21st century, while consumer's demand for sustainability drives the search for new active natural ingredients and the development of green extractions techniques. The aim of this work is to obtain antioxidant-enriched extracts from two seaweeds found on the Portuguese shore, Sargassum muticum and Gelidium corneum using natural deep eutectic solvents (NADES) to be used in cosmetic formulations. Extracts were obtained by maceration of powdered seaweeds with aqueous solutions (25 % (v/v) in water) of different NADES, L-lactic acid: fructose (5:1), L-lactic acid: glucose (5:1) and L-lactic acid: sodium acetate (7:1). The resulting extracts were evaluated regarding their total phenolic content (TPC) using the Folin-Ciocalteu method and antioxidant capacity by the DPPH and FRAP assays. L-lactic acid: fructose (5:1) NADES yielded Sargassum muticum extracts with the highest phenolic content (2099 mg GAE/L) and the highest antioxidant activities (DPPH reduction of 27 %, FRAP 30 μM FeSO4). Antimicrobial activity of the extracts over three microorganisms of the skin microbiota, the bacteria Staphylococcus epidermidis and Cutibacterium acnes and the fungus Malassezia furfur, revealed no relevant antimicrobial effect, meaning that extracts did not affect the skin microbiota homeostasis. The extract with the highest cosmeceutical interest, S. muticum extract prepared using L-lactic acid: fructose (7:1), was incorporated into a topical O/W emulsion. Physical and rheology data of the cosmetic formulation ensure its quality and safety. Finally, compatibility, acceptability and antioxidant efficacy were evaluated in vivo, in human volunteers. The results show that NADES are a promising replacement of conventional solvents in the extraction of antioxidants from biomass and their use in topical formulations is safe.

Plant-Based Films and Hydrogels for Wound Healing.

Skin is constantly exposed to injury and infectious agents that can compromise its structural integrity and cause wounds. When this occurs, microorganisms from the skin microbiota and external bacteria and fungi can penetrate the wound and cause an infection, which complicates the healing process. Nowadays, there are several types of wound dressings available to treat wounds, some of which are incorporated with antimicrobial agents. However, the number of microorganisms resistant to these substances is rising. Therefore, the search for new, natural alternatives such as essential oils (EOs) and plant extracts (PEs) is on the rise. However, these substances present some limitations (poor bioavailability and poor target capacity), which limits their efficiency. Their incorporation in formulations in the form of films and hydrogels (HGs) can help to overcome these issues and may be a potential alternative to the current treatments. HGs and films incorporated with PEs and EOs have antimicrobial activity, promote the viability of skin cells and fibroblast migration, and are non-toxic and biocompatible. This review discusses the use of films and HGs for the topical delivery of EOs and PEs for wound treatment and their formulations as effective wound dressings, while debating some mechanisms and biological properties to elucidate their presumptive clinical relevance and possible applications.

Melatonin restores DNFB-induced dysbiosis of skin microbiota in a mouse model of atopic dermatitis

BackgroundThe epidermic microbiota plays crucial roles in the pathogenesis of atopic dermatitis (AD), a common inflammatory skin disease. Melatonin (MLT) has been shown to ameliorate skin damage in AD patients, yet the underlying mechanism is unclear. MethodsUsing 2,4-dinitrofluorobenzene (DNFB) to induce an AD model, MLT intervention was applied for 14 days to observe its pharmaceutical effect. Skin lesions were observed using HE staining, toluidine blue staining and electron microscopy. Dermal proinflammatory factor (IL-4 and IL-13) and intestinal barrier indices (ZO1 and Occludin) were assessed by immunohistochemistry and RT–qPCR, respectively. The dysbiotic microbiota was analyzed using 16S rRNA sequencing. ResultsMLT significantly improved skin lesion size; inflammatory status (mast cells, IgE, IL-4, and IL-13); and the imbalance of the epidermal microbiota in AD mice. Notably, Staphylococcus aureus is the key bacterium associated with dysbiosis of the epidermal microbiota and may be involved in the fine modulation of mast cells, IL-4, IL-13 and IgE. Correlation analysis between AD and the gut revealed that intestinal dysbiosis occurred earlier than that of the pathological structure in the gut. ConclusionMelatonin reverses DNFB-induced skin damage and epidermal dysbiosis, especially in S. aureus.

Proteomic, miRNA and bacterial biomarker patterns in atopic dermatitis patients and their course upon anti-IL-4Rα therapy.

Identification of biomarkers is required for a systems medicine approach and personalized treatment in atopic dermatitis (AD). These biomarkers may not only aid in diagnosing but also might be suitable to predict the effectiveness of targeted treatment. We aimed to identify proteomic, microbial and miRNA biomarkers in AD patients and investigated their course in relation to the clinical response upon anti-IL-4Rα therapy. Proteomic and miRNA screening was performed in AD patients in comparison to healthy controls. Differentially regulated serum proteins, miRNA and selected skin microbiota were measured consecutively in 50 AD patients before and upon systemic dupilumab treatment. A random forest classifier was used to predict the outcome of dupilumab therapy based on the initial biomarker patterns. We identified 27 proteomic candidates, miRNA and three microbial strains to be dysregulated in AD. CCL17, CCL13, CCL22, E-selectin and BDNF were differently regulated and significantly associated with treatment response. In contrast, neither the microbial composition nor the miRNA pattern was associated with treatment response upon dupilumab treatment. AD patients display defined dysregulations regarding their systemic proteomic serum profile, miRNA patterns and their skin microbiome. The proteomic profile and selected skin bacteria changed profoundly upon anti-IL-4Rα therapy which was associated with an overall clinical response. This was not seen in miRNA-related biomarkers. Our findings support the hypothesis that biomarker profiles reflect treatment responses and may in the future be used to develop a personalized medicine approach for the treatment of AD patients.

Inhibition of Biofilm Formation in Cutibacterium acnes, Staphylococcus aureus, and Candida albicans by the Phytopigment Shikonin.

Skin microbiota, such as acne-related Cutibacterium acnes, Staphylococcus aureus, and fungal Candida albicans, can form polymicrobial biofilms with greater antimicrobial tolerance to traditional antimicrobial agents and host immune systems. In this study, the phytopigment shikonin was investigated against single-species and multispecies biofilms under aerobic and anaerobic conditions. Minimum inhibitory concentrations of shikonin were 10 µg/mL against C. acnes, S. aureus, and C. albicans, and at 1-5 µg/mL, shikonin efficiently inhibited single biofilm formation and multispecies biofilm development by these three microbes. Shikonin increased porphyrin production in C. acnes, inhibited cell aggregation and hyphal formation by C. albicans, decreased lipase production, and increased hydrophilicity in S. aureus. In addition, shikonin at 5 or 10 µg/mL repressed the transcription of various biofilm-related genes and virulence-related genes in C. acnes and downregulated the gene expression levels of the quorum-sensing agrA and RNAIII, α-hemolysin hla, and nuclease nuc1 in S. aureus, supporting biofilm inhibition. In addition, shikonin prevented multispecies biofilm development on porcine skin, and the antimicrobial efficacy of shikonin was recapitulated in a mouse infection model, in which it promoted skin regeneration. The study shows that shikonin inhibits multispecies biofilm development by acne-related skin microbes and might be useful for controlling bacterial infections.

Metagenomic profiling of viral and microbial communities from the pox lesions of lumpy skin disease virus and sheeppox virus-infected hosts.

It has been recognized that capripoxvirus infections have a strong cutaneous tropism with the manifestation of skin lesions in the form of nodules and scabs in the respective hosts, followed by necrosis and sloughing off. Considering that the skin microbiota is a complex community of commensal bacteria, fungi and viruses that are influenced by infections leading to pathological states, there is no evidence on how the skin microbiome is affected during capripoxvirus pathogenesis. In this study, shotgun metagenomic sequencing was used to investigate the microbiome in pox lesions from hosts infected with lumpy skin disease virus and sheep pox virus. The analysis revealed a high degree of variability in bacterial community structures across affected skin samples, indicating the importance of specific commensal microorganisms colonizing individual hosts. The most common and abundant bacteria found in scab samples were Fusobacterium necrophorum, Streptococcus dysgalactiae, Helcococcus ovis and Trueperella pyogenes, irrespective of host. Bacterial reads belonging to the genera Moraxella, Mannheimia, Corynebacterium, Staphylococcus and Micrococcus were identified. This study is the first to investigate capripox virus-associated changes in the skin microbiome using whole-genome metagenomic profiling. The findings will provide a basis for further investigation into capripoxvirus pathogenesis. In addition, this study highlights the challenge of selecting an optimal bioinformatics approach for the analysis of metagenomic data in clinical and veterinary practice. For example, direct classification of reads using a kmer-based algorithm resulted in a significant number of systematic false positives, which may be attributed to the peculiarities of the algorithm and database selection. On the contrary, the process of de novo assembly requires a large number of target reads from the symbiotic microbial community. In this work, the obtained sequencing data were processed by three different approaches, including direct classification of reads based on k-mers, mapping of reads to a marker gene database, and de novo assembly and binning of metagenomic contigs. The advantages and disadvantages of these techniques and their practicality in veterinary settings are discussed in relation to the results obtained.

Multiple subcutaneous abscesses by Corynebacterium amycolatum in a patient with severe idiopathic aplastic anaemia

AbstractCorynebacterium amycolatum is a part of the normal skin flora and has been underestimated as a pathogen. However, in recent years, the species has gained recognition as an important pathogen causing severe infections, particularly in immunocompromised patients. Nevertheless, identifying these organisms at the species level is difficult in routine clinical microbiology, leading to limited knowledge of their clinical manifestations in infectious diseases. In this study, we report a rare case of multiple subcutaneous abscesses in a patient with severe neutropenia, wherein C.amycolatum was identified as the causative organism through genotyping tests. This case highlights the importance of this organism as an aetiological agent of severe skin infections in patients with compromised immune systems.

Virulence determinants and antibiotic resistance in staphylococci isolated from the skin of captive bred reptiles

Knowledge of the composition and properties of skin microbiota in healthy reptiles is essential for preservation strategies and thus the prevention of skin dysbiosis leading to dermatological diseases. Despite the greatly increasing popularity of reptiles as pets, only a few studies have dealt with this topic. Therefore, the aim of this work was to analyse species composition of bacteria isolated from skin swabs of 40 reptiles (17 species) using MALDI-TOF spectrometry and to characterise the virulence properties of identified staphylococci (n = 51). The most common species were Staphylococcus xylosus and S. sciuri. Bacilli, enterococci, Escherichia coli, Salmonella sp. and Acinetobacter sp. were also common. The most frequent antimicrobial resistance in staphylococcal isolates was observed for ampicillin (100.0%) and cefoxitin (98.0%) with the blaZ gene being most prevalent (58.8%). In contrast, all staphylococci were susceptible to gentamicin, kanamycin and imipenem. Slime and biofilm production was observed in 86.3% and 76.5% of isolates, respectively. Gelatinase, DNase, protease and lipase activity was found more rarely (41.2%; 25.5%; 27.5% and 21.6%). Since reptiles are a reservoir of bacteria for their owners, common multi-drug resistance (84.3%, MAR index average 0.29 ± 0.09) and biofilm formation must be kept in mind, especially in the case of injury when handling reptiles.

Etiology and epidemiology of digital dermatitis in Australian dairy herds

Bovine digital dermatitis (BDD) is an important cause of lameness in dairy cows worldwide. However, very little is known about this disease in Australian herds, which are predominantly managed on pasture. The primary objectives of this cross-sectional study were to describe the presence and prevalence of BDD in Australian dairy herds and to characterize the microbiota of healthy skin and M4 lesions of BDD-affected, pasture-managed cows. Cows from 71 dairy herds were examined at milking time to identify the presence of BDD lesions. True prevalence was estimated using Bayesian methods with informative priors for sensitivity and specificity. Biopsy samples (n = 60) were collected from cows with and without BDD lesions in 7 pasture-based herds. The microbiota in the superficial and deep strata of each tissue biopsy were characterized via sequencing of the V3-V4 region of the bacterial ribosomal RNA gene. Lesions were detected in 1,817 (11.5%) of 15,813 cows and in 68 of 71 (95.8%) herds. The median herd-level apparent and true prevalences of BDD were 8.5% and 18.1%, respectively, but prevalences varied considerably between farms. On farms with BDD, M4 lesions accounted for 70% to 100% of all lesions (interquartile range = 95.1%-100%, median = 100%); M2 lesions (i.e., large ulcerative lesions) were observed at low prevalence (<2.2%) in the few herds (7/71, 9.9%) where they were found. There was a significant difference in the composition of the microbiota between healthy skin and M4 lesions but not between superficial and deep tissue layers. Several gut- and effluent-associated bacterial taxa, including Lentimicrobium and Porphyromonas, which have previously been associated with BDD, were abundant in BDD lesions but not in control biopsies. Our study supports the idea that such taxa are involved in, although possibly not essential to, lesion development and persistence in pasture-managed cows in Australia. Our results also suggest that Dichelobacter may contribute to the disease process. We conclude that BDD is likely to occur in most Australian dairy farms, but that further studies are needed to identify its effect on cow welfare and productivity. Further investigation of the etiology of BDD in Australian dairy herds is also necessary to inform prevention and control strategies.

(044) Does Time of Intraoperative Exposure to the Aerobiome Increase Microbial Growth on Inflatable Penile Prostheses?

Abstract Introduction The use of inflatable penile prostheses (IPP) is a fundamental approach in managing erectile dysfunction that does not respond to medical management. Approximately 28,000 IPPs are implanted annually in the United States. Device infection, with an incidence up to 3%, is a particularly concerning complication as management generally necessitates device removal. This can result in significant cost burden, requiring inpatient admission, return to operative room and extensive postoperative care. One important risk factor for IPP infection is operative time, with the suggestion that increased operative time facilitates a colonization of microbes from the skin flora and ambient air within the operating room (referred to as the aerobiome). Objective To evaluate whether increased exposure to the operating room (OR) aerobiome results in increased microbial colonization of IPPs. Methods We performed an ex vivo study focusing on the reservoir and tips of Coloplast Titan IPP. Conditions of an IPP surgery were attempted to be closely replicated. Setup included a dedicated table within the same institutional OR where IPPs are routinely performed, facilitating sample collection, and with standard intra-operative conditions-pressure 0.024”WC, temperature 66.80F, and humidity 49.2% RH-to emulate surgical conditions. Stringent surgical hygiene was observed to obtain samples in a sterile manner; this including surgical scrub, sterile field, and double-glove technique. A sterile swab was collected at 30-minute intervals over a total duration of 3 hours, from each individual component of the IPP, resulting in a total of 6 samples per component. To prevent any potential interference from previous samples, care was taken to collect each swab from distinct areas. The obtained swabs were subjected to quantitative polymerase chain reaction (qPCR) and next generation sequencing (NGS) analyses of the V12 16S rRNA conservative region using the MiSeq platform (Illumina, San Diego, CA) with 2x250 paired read chemistry. Subsequent bioinformatic processing was carried out utilizing a clustering-based method with operational taxonomic units set at a 97% similarity threshold, and taxonomic assignment was accomplished using an internally maintained taxonomic classifier. Results The results of the study, obtained through both standard culture and next-generation sequencing (NGS) analyses, demonstrated consistent and significant findings. Through rigorous examination, it was determined that no microbial growth was detected on any component of the inflatable penile prostheses (IPPs) throughout the entire duration of the experiment, which lasted up to 3 hours. This dual approach of standard culture and NGS provided comprehensive and robust evidence of the absence of microbial colonization on the IPP devices. Conclusions These findings suggest that the duration of exposure to the OR aerobiome alone does not appear to increase the risk of microbial colonization on IPP devices. Further ex vivo studies are needed to support these findings and evaluate whether factors such as time of skin-to-IPP contact or changes in OR conditions contribute to risk of IPP microbial colonization. Disclosure Any of the authors act as a consultant, employee or shareholder of an industry for: Coloplast, Boston Scientific.