Characteristics of Malassezia furfur at various pH and effects of Malassezia lipids on skin cells.

Malassezia species are commensal and opportunistic fungi found in human skin. All Malassezia species lack fatty acid synthesis genes and survive by utilizing several lipases to degrade and absorb fatty acids from external lipid sources, but little research has been done on their optimal active pH and temperature. Our skin protects itself from external stimuli and maintains homeostasis, involving bacteria and fungi such as Malassezia species that inhabit our skin. Hence, dysbiosis in the skin microbiome can lead to various skin diseases. The skin's pH is slightly acidic compared to neutral, and changes in pH can affect the metabolism of Malassezia species. We used keratinocyte cell lines to determine the effect of lipids bio-converted by Malassezia furfur, Malassezia japonica, and Malassezia yamatoensis under pH conditions similar to those of healthy skin. Lipids bio-converted from Malassezia species were associated with the regulation of transcripts related to inflammation, moisturizing, and promoting elasticity. Therefore, to determine the effect of pH on lipid metabolism in M. furfur, which is associated with seborrheic dermatitis, changes in biomass, lipid content, and fatty acid composition were determined. The results showed that pH 7 resulted in low growth and reduced lipid content, which had a negative impact on skin health. Given that bio-converted Malassezia-derived lipids show positive effects at the slightly acidic pH typical of healthy skin, it is important to study their effects on skin cells under various pH conditions. KEY POINTS: • pH 6, Malassezia spp. bio-converted lipid have a positive effect on skin cells • Malassezia spp. have different lipid, fatty acid, and growth depending on pH • Malassezia spp. can play a beneficial role by secreting lipids to the outside.

A bibliometric and visual analysis of the research status and hotspots of seborrheic dermatitis based on web of science.

BACKGROUND: Seborrheic dermatitis (SD) is a common chronic inflammatory skin disease. In recent years, significant progress has been made in the field of SD, but there has been no bibliometric research yet. This study aims to use bibliometric methods to analyze the current research status and hot topics of SD, to understand further the research trends and future development prospects in this field. METHODS: Retrieve core literature on SD from the Web of Science database and conduct a detailed analysis using CiteSpace and VOSviewer software based on factors such as publication volume, countries (regions), research institutions, journals, authors, highly-cited papers, and keywords. RESULTS: From 1996 to 2024, a total of 1436 publications were included in the bibliometric analysis. The number of publications has shown an increasing trend year by year. The USA is the leading country in this field of research. The University of California System is the primary research institution. The International Journal of Dermatology is the journal with the highest number of publications. The author Yang Won Lee has the highest number of publications, while the article "Seborrheic Dermatitis" (2004) by Gupta, A.K. has been cited the most. "Seborrheic dermatitis" is the most frequently occurring keyword. The main research hotspots and frontiers in SD are as follows: (1) The relationship between SD and other skin diseases is a popular research topic; (2) Malassezia and inflammation are current research hotspots in SD; and (3) Focusing on antifungal and anti-inflammatory treatments for SD is the current frontier direction in this field. CONCLUSION: This study is a summary of the current status and hot trends of SD research, which helps clinical doctors and researchers quickly understand the insights and valuable information of SD research and provides reference for clinical decision-making and finding future research directions.

Saiba sobre a dermatite seborreica (ou caspa!) | Coisa de Homem

Você já ouviu falar em dermatite seborreica? Bom, talvez não por este nome! A condição inflamatória é popularmente conhecida como caspa e no Coisa de Homem, desta quarta-feira (27), você sabe mais sobre os sintomas e as formas de prevenção.

Nutrition, Obesity, and Seborrheic Dermatitis: Systematic Review.

BACKGROUND: Pathogenesis of seborrheic dermatitis involves lipid secretion by sebaceous glands, Malassezia colonization, and an inflammatory response with skin barrier disruption. Each of these pathways could be modulated by diet, obesity, and nutritional supplements. Current treatment options provide only temporary control of the condition; thus, it is essential to recognize modifiable lifestyle factors that may play a role in determining disease severity. OBJECTIVE: This study aimed to summarize published evidence on diet, nutritional supplements, alcohol, obesity, and micronutrients in patients with seborrheic dermatitis and to provide useful insights into areas of further research. METHODS: A literature search of Scopus, PubMed, and MEDLINE (Ovid interface) for English language papers published between 1993 and 2023 was conducted on April 16, 2023. Case-control studies, cohort studies, and randomized controlled trials with 5 or more subjects conducted on adult participants (>14 years) were included, case reports, case series, and review papers were excluded due to insufficient level of evidence. RESULTS: A total of 13 studies, 8 case-control, 3 cross-sectional, and 2 randomized controlled trials, involving 13,906 patients were included. Seborrheic dermatitis was correlated with significantly increased copper, manganese, iron, calcium, and magnesium concentrations and significantly lower serum zinc and vitamin D and E concentrations. Adherence to the Western diet was associated with a higher risk for seborrheic dermatitis in female patients and an increased consumption of fruit was associated with a lower risk of seborrheic dermatitis in all patients. The prebiotic Triphala improved patient satisfaction and decreased scalp sebum levels over 8 weeks. Most studies find associations between regular alcohol use and seborrheic dermatitis, but the association between BMI and obesity on seborrheic dermatitis severity and prevalence is mixed. CONCLUSIONS: This review sheds light on specific promising areas of research that require further study, including the need for interventional studies evaluating serum zinc, vitamin D, and vitamin E supplementation for seborrheic dermatitis. The negative consequences of a Western diet, alcohol use, obesity, and the benefits of fruit consumption are well known; however, to fully understand their specific relationships to seborrheic dermatitis, further cohort or interventional studies are needed. TRIAL REGISTRATION: PROSPERO CRD42023417768; https://tinyurl.com/bdcta893.

The Global Prevalence of Seborrheic Dermatitis: A Systematic Review and Meta-Analysis.

Importance: Seborrheic dermatitis is a prevalent chronic inflammatory skin disease, yet its global prevalence, pathogenesis, and epidemiology remain inadequately defined. Objective: To provide a detailed estimation of the global prevalence of seborrheic dermatitis, analyze demographic variations, and explore differences in various settings. Data Sources: Embase, PubMed, Scopus, and Cochrane Database of Systematic Reviews were searched from inception through October 2023. Study Selection: Original investigations on seborrheic dermatitis prevalence were included after duplicate screening of titles, abstracts, and full articles, including only studies with clinician-diagnosed cases. Data Extraction and Synthesis: Following PRISMA guidelines, data were extracted and quality was assessed independently by multiple reviewers. A random-effects model using restricted maximum likelihood was used for meta-analysis and subgroup analyses. Main Outcome and Measure: The primary outcome was the pooled estimate of global seborrheic dermatitis prevalence. Results: From 1574 identified articles, 121 studies were included, encompassing 1 260 163 individuals and revealing a pooled global seborrheic dermatitis prevalence of 4.38% (95% CI, 3.58%-5.17%), with significant heterogeneity (I2 = 99.94%). Subgroup analyses showed variations by age, with a higher prevalence in adults (5.64% [95% CI, 4.01%-7.27%]) compared to children (3.70% [95% CI, 2.69%-4.80%]) and neonates (0.23% [95% CI, 0.04%-0.43%]). Geographic analyses indicated variability, with the highest prevalence in South Africa (8.82% [95% CI, 3.00%-14.64%]) and the lowest in India (2.62% [95% CI, 1.33%-3.92%]). Conclusions and Relevance: This comprehensive meta-analysis provides a detailed estimation of the global prevalence of seborrheic dermatitis, highlighting significant variability across different demographics and settings.

Scalp microbiome: a guide to better understanding scalp diseases and treatments.

The scalp microbiome represents an array of microorganisms important in maintaining scalp homeostasis and mediating inflammation. Scalp microbial dysregulation has been implicated in dermatologic conditions including alopecia areata (AA), dandruff/seborrheic dermatitis (D/SD), scalp psoriasis (SP) and folliculitis decalvans (FD). Understanding the impact of scalp microbial dysbiosis gives insight on disease pathophysiology and guides therapeutic decision making. Herein we review the scalp microbiome and its functional role in scalp conditions by analysis of metagenomic medical literature in alopecia, D/SD, SP, and other dermatologic disease.Increased abundance of Malassezia, Staphylococcus, and Brevibacterium was associated with SD compared to healthy controls. A higher proportion of Corynebacterium, actinobacteria, and firmicutes are present in AA patients, and lower proportions of Staphylococcus caprae are associated with worse clinical outcomes. Decreased prevalence of actinobacteria and Propionibacterium and increased firmicutes, staphylococcus, and streptococcus are associated with scalp psoriasis. Studies of central centrifugal cicatricial alopecia (CCCA) suggest scalp microbial composition contributes to CCCA's pro-inflammatory status. The most common organisms associated with FD include methicillin-resistant S. aureus and S. lugdunensis. Antifungals have been a mainstay treatment for these diseases, while other alternatives including coconut oils and shampoos with heat-killed probiotics have shown considerable potential efficacy by replenishing the scalp microbiome.

Treatment of Common Dermatologic Conditions.

Dermatologic concerns are discussed in about a third of all primary care visits. This review discusses treatments for common dermatologic diagnoses addressed in primary care settings, with an emphasis on new and emerging treatments. Topical, oral, and injectable treatment of common forms of alopecia, facial rashes, atopic dermatitis, psoriasis, seborrheic dermatitis, and stasis dermatitis will be discussed to help increase comfort in prescribing and alert providers to common side effects or complications of more intensive treatments used by dermatologists.

Common Skin Conditions in Children and Adolescents: Atopic and Seborrheic Dermatitis.

Atopic dermatitis (AD) is a chronic, recurring, inflammatory skin condition. Xerosis, pruritus, and rash make the clinical diagnosis. Adequate skin care and regular emollient use are key in management. Topical corticosteroids are the first-line treatment for AD flare-ups. Wet wrap therapy can improve AD severity and extent. Topical calcineurin inhibitors are second-line treatments. Emollient use, topical corticosteroids and calcineurin inhibitors, and bleach baths can help prevent flare-ups. Patients with refractory AD that might require immunomodulatory treatments, such as dupilumab (Dupixent), Janus kinase inhibitors, or phototherapy, should be referred to a dermatologist. Seborrheic dermatitis (SD) is a common, chronic, relapsing, inflammatory condition that involves sebaceous skin areas. Infection with Malassezia species and the inflammatory response to it are the probable etiologies. The clinical diagnosis is made by the presence of hallmark greasy, yellow scales on the scalp or face. Infantile SD most commonly involves the scalp and forehead and typically is self-limited. In infants, application of emollients followed by hair brushing and shampooing may be effective. In infants and children, if the condition does not improve with this treatment, topical ketoconazole shampoo, gel, or lotion is safe and effective. Refractory cases of SD can be managed with topical corticosteroids and calcineurin inhibitors.

A comprehensive literature review and an international expert consensus on the management of scalp seborrheic dermatitis in adults.

Seborrheic Dermatitis of the scalp (SSD) is a chronic and relapsing inflammatory skin condition. Current SSD treatments mainly consist of topical applications of anti-fungals and anti-inflammatory agents. to review information about SSD and to provide dermatologists with practical recommendations for managing adult SSD. Material and methods: Between September and December 2023, an international group of experts in dermatology and hair and scalp disorders met to discuss published data about SD, SSD, dandruff, and management options. A total of 131 manuscripts available from PubMed were analysed, discussed and used for the present consensus. Each author was asked to complete a table listing currently used treatments to treat SSD according to the literature and to their own experience. The authors confirmed their use and regimen and commented on local treatment exceptions. They then agreed on prescription practices and proposed a general treatment approach. Currently, approved therapies to manage moderate and severe forms of SSD do not exist and there is a need for adapted and approved medications that treat efficiently and safely the disease. We propose a treatment algorithm that allows for the treatment of all severity grades of SSD. This algorithm may be completed with local treatment specifications. Despite the lack of approved therapies to manage moderate forms of SSD, a treatment algorithm is proposed and may help prescribers to manage SSD more efficiently.

Topical moisturizer with rose stem cell-derived exosomes (RSCEs) for recalcitrant seborrheic dermatitis: A case report with 6 months of follow-up.

INTRODUCTION: Seborrheic dermatitis (SD) poses significant treatment challenges due to its chronic nature and the side effects associated with long-term use of conventional therapies like topical corticosteroids. In the search for alternative treatments, exosomes, particularly those derived from rose stem cells (RSCEs), offer a promising avenue due to their potential in managing chronic skin conditions. OBJECTIVE: This case report examines the efficacy of a topical moisturizer containing RSCEs in treating a patient with refractory SD, aiming to provide an alternative treatment pathway. MATERIALS AND METHODS: A 40-year-old male with a long-standing history of SD, unresponsive to traditional treatments, underwent a novel treatment regimen. This regimen included an initial topical application of 2.5 mL of RSCEs followed by a maintenance phase involving the application of a RSCE-containing moisturizer. Clinical outcomes were assessed through the Patient's Global Assessment (PGA) and Investigator's Global Assessment (IGA) scores, along with evaluations of scaling and erythema. RESULTS: Remarkable clinical improvement was noted as early as 1-day post-treatment, with significant reductions in redness, scaling, and itching. The patient experienced sustained relief throughout the 6-month follow-up, with a recurrence in the sixth month that was less severe than previous flare-ups. This demonstrated not only the efficacy of RSCEs in symptom management but also their potential in extending remission periods. CONCLUSION: The chronic management of SD can benefit from innovative treatments like the RSCE-containing moisturizer, as shown in this case report. While the observed outcomes are promising, indicating substantial improvements in skin condition and symptom management, larger controlled studies are necessary to validate the therapeutic potential of exosome-containing moisturizers fully. This case underscores the need for alternative therapies in SD treatment, highlighting the role of exosomes as a viable option.

Malassezia-associated skin diseases in the pediatric population.

Malassezia are yeast species that commonly colonize healthy skin. However, they have been associated with or implicated in the pathogenesis of numerous skin disorders, particularly in the setting of pediatric populations. In this review, we will focus on several Malassezia-associated skin conditions manifesting in infants, children, and adolescents: pityriasis versicolor, Malassezia folliculitis, infantile and adolescent seborrheic dermatitis, head and neck dermatitis, and neonatal cephalic pustulosis. We examine the literature and provide an overview of these conditions, including clinical presentation in diverse skin colors, diagnosis, risk factors, and treatment and management. Additionally, we summarize and highlight some of the proposed theories on the role of Malassezia spp. in the pathogenesis of these skin conditions.

What you need to know about common skin problems in older adults.

Skin ageing is a multifaceted process impacted by both intrinsic and extrinsic factors. Drier and less elastic skin with declining sebum levels in older age makes ageing skin more vulnerable to various skin conditions, including infections, inflammatory dermatoses, and cancers. Skin problems are common among older adults due to the effects of ageing, polypharmacy and multimorbidity impacting not only physical health but wellbeing and quality of life. In the UK, older adults in geriatric medicine wards may present with various skin conditions. Hospitalised older individuals may have undiagnosed skin problems unrelated to their admission, making hospitalisation an opportunity to manage unmet needs. Asteatotic eczema, incontinence associated dermatitis, seborrhoeic dermatitis, chronic venous insufficiency, and cellulitis are common disorders clinicians encounter in the geriatric medicine wards. This article outlines the importance of performing comprehensive skin assessments to help diagnose and commence management for these common conditions.

Sebaceous gland atrophy due to seborrheic dermatitis in a patient with alopecia: A potential pitfall.

Seborrheic dermatitis is an inflammatory condition that usually presents with erythema, scaly greasy papules, and plaques affecting sebaceous gland-rich areas and predominantly involving the face and scalp. The diagnosis of seborrheic dermatitis can often be rendered based on the clinical presentation. However, in certain cases, a biopsy can be useful to distinguish it from clinical mimics such as psoriasis, discoid lupus, and rosacea. Prominent sebaceous gland atrophy without scarring has been well-described as an important and relatively specific clue for psoriatic or drug-induced alopecia. However, sebaceous gland atrophy is not specific to psoriasis and has been demonstrated in seborrheic dermatitis, facial discoid dermatitis, and potentially may occur in other inflammatory dermatoses of the scalp. We report a 23-year-old female patient presenting with non-scarring hair loss and histopathological findings demonstrating mild androgenetic alopecia and changes of seborrheic dermatitis with dramatic sebaceous gland atrophy. The patient had no history or evidence of psoriasis clinically. Our case suggests that in patients with seborrheic dermatitis, sebaceous gland atrophy may complicate the evaluation of alopecia biopsies and should be recognized as a pitfall. Seborrheic dermatitis should be included in the differential diagnosis of alopecia biopsies showing prominent sebaceous gland atrophy.

Association of air pollution with incidence of late-onset seborrhoeic dermatitis: a prospective cohort study in UK Biobank.

BACKGROUND: Late-onset seborrhoeic dermatitis seriously affects patients' quality of life. Studies have shown an association between air pollution and other inflammatory skin diseases. However, associations between air pollution exposures and the incidence of late-onset seborrhoeic dermatitis have not been elucidated. OBJECTIVES: To investigate air pollution's role in the incidence of late-onset seborrhoeic dermatitis. METHODS: We engaged a prospective cohort analysis utilizing the UK Biobank database. Exposure data spanning various years for specific air pollutants, namely particulate matter [PM; with an aerodynamic diameter of ≤ 2.5 µm (PM2.5), between 2.5 and 10 µm (PM2.5-10), ≤ 10 µm (PM10)] along with nitrogen oxides (NO plus NO2, denoted NOx) and NO2, were incorporated. Through a composite air pollution score constructed from five pollutants and employing Cox proportional hazards models, the relationship between air pollution and seborrhoeic dermatitis was delineated. RESULTS: Our examination of 193 995 participants identified 3363 cases of seborrhoeic dermatitis. Higher concentrations of specific pollutants, particularly in the upper quartile (Q4), were significantly linked to an elevated risk of seborrhoeic dermatitis. Notably, PM2.5, PM10, NO2 and NOx exhibited hazard ratios of 1.11, 1.15, 1.22 and 1.15, respectively. The correlation was further solidified with a positive association between air pollution score increments and onset of seborrhoeic dermatitis. Intriguingly, this association was accentuated in certain demographics, including younger men, socioeconomically deprived people, smokers, daily alcohol consumers, and those engaging in regular physical activity. CONCLUSIONS: Our findings revealed that air pollution exposures were associated with incidence of late-onset seborrhoeic dermatitis. These results emphasize the importance of preventing environmental air pollution exposures to mitigate the risk of developing the condition.

Enhancing assisted diagnostic accuracy in scalp psoriasis: A Multi-Network Fusion Object Detection Framework for dermoscopic pattern diagnosis.

BACKGROUND: Dermoscopy is a common method of scalp psoriasis diagnosis, and several artificial intelligence techniques have been used to assist dermoscopy in the diagnosis of nail fungus disease, the most commonly used being the convolutional neural network algorithm; however, convolutional neural networks are only the most basic algorithm, and the use of object detection algorithms to assist dermoscopy in the diagnosis of scalp psoriasis has not been reported. OBJECTIVES: Establishment of a dermoscopic modality diagnostic framework for scalp psoriasis based on object detection technology and image enhancement to improve diagnostic efficiency and accuracy. METHODS: We analyzed the dermoscopic patterns of scalp psoriasis diagnosed at 72nd Group army hospital of PLA from January 1, 2020 to December 31, 2021, and selected scalp seborrheic dermatitis as a control group. Based on dermoscopic images and major dermoscopic patterns of scalp psoriasis and scalp seborrheic dermatitis, we investigated a multi-network fusion object detection framework based on the object detection technique Faster R-CNN and the image enhancement technique contrast limited adaptive histogram equalization (CLAHE), for assisting in the diagnosis of scalp psoriasis and scalp seborrheic dermatitis, as well as to differentiate the major dermoscopic patterns of the two diseases. The diagnostic performance of the multi-network fusion object detection framework was compared with that between dermatologists. RESULTS: A total of 1876 dermoscopic images were collected, including 1218 for scalp psoriasis versus 658 for scalp seborrheic dermatitis. Based on these images, training and testing are performed using a multi-network fusion object detection framework. The results showed that the test accuracy, specificity, sensitivity, and Youden index for the diagnosis of scalp psoriasis was: 91.0%, 89.5%, 91.0%, and 0.805, and for the main dermoscopic patterns of scalp psoriasis and scalp seborrheic dermatitis, the diagnostic results were: 89.9%, 97.7%, 89.9%, and 0.876. Comparing the diagnostic results with those of five dermatologists, the fusion framework performs better than the dermatologists' diagnoses. CONCLUSIONS: Studies have shown some differences in dermoscopic patterns between scalp psoriasis and scalp seborrheic dermatitis. The proposed multi-network fusion object detection framework has higher diagnostic performance for scalp psoriasis than for dermatologists.