An update on the microbiology, immunology and genetics of seborrheic dermatitis

Efficacy of Lacticaseibacillus rhamnosus probiotic strains in treating chromate induced dermatitis

Chromate induced dermatitis is a significant occupational health concern. Chromate (Cr) resistant Lacticaseibacillus rhamnosus strains were isolated from commercial probiotic sachets PREPRO and HiFLORA. Among 13 Cr-resistant bacterial isolates, six were selected based on high chromate resistance at 500 ug/ml. Selected isolates were subjected to biochemical and molecular characterization and in vivo analyses. DPC assay was conducted under controlled conditions in order to determine the reduction potential of the isolated bacteria. The selected isolates were identified as L. rhamnosus-L1 (PP493917), L. rhamnosus-L2 (PP493918), L. rhamnosus-L3 (PP493921) L. rhamnosus-L4 (PP493920) L. rhamnosus-L8 (PP493922) and L. rhamnosus-L12 (PP493923). Lacticaseibacillus rhamnosus L1showed highest resistance against Cr (VI) with reduction potential 56%. In vivo experiments were performed to assess the healing effects of isolated bacterial strains on mice skin, with Hematoxylin and Eosin (H&E) staining used to identify severe dermatitis in skin tissue and evaluate therapeutic effects of probiotic strains. The structural determination of flavin reductase protein of L. rhamnosus was carried out using bioinformatics tools. These tools predicted the structural-based functional homology of flavin reductase protein in bacterial Cr (VI)-detoxification system. Lacticaseibacillus rhamnosus can be effectively used against chromate-induced dermatitis due to its high chromate resistance and reduction potential.

Seborrheic Dermatitis: Exploring the Complex Interplay with Malassezia

Seborrheic dermatitis (SD) is a chronic inflammatory skin condition often involving the sebaceous-rich areas, characterized by erythematous scaly lesions. It is frequently observed in individuals with immune dysregulation, suggesting the interplay between the immune system and disease development. An altered immune environment leads to an exaggerated inflammatory response with the activation of innate immunity, involving the participation of mast cells, γδ T cells, and the NOD-LRR-pyrin-domain-containing protein 3 (NLRP3) inflammasome. This review aims to assess the complex relationship between Malassezia and the immune system in the pathogenesis of SD. We will explore how an impaired immune response predisposes the skin to Malassezia overgrowth and infection. We will examine the role of adaptive immunity, particularly T helper cells, in driving chronic inflammation in SD. All actors involved, whether part of innate or adaptive immunity, are responsible for the release of pro-inflammatory cytokines, which contribute to the progression of the disease. Therapeutic strategies aimed at the modulation of the immune response in SD have been tested in clinical trials evaluating the efficacy of immunomodulatory treatments in the management of SD. This review synthesizes insights from immunological studies and clinical trials to present an in-depth analysis of the immune mechanisms underpinning SD, thereby proposing targeted therapeutic strategies for its management.

Potential Applications of Chitosan in Seborrheic Dermatitis and Other Skin Diseases: A Comprehensive Review

This review article explores the potential applications of chitosan, a natural polysaccharide derived from crustacean shells, in the treatment of seborrheic dermatitis (SD) and other skin diseases. SD is a common chronic inflammatory skin condition characterized by erythema, scaling, itching, and an oily appearance, predominantly affecting areas rich in sebaceous glands. Current treatments, including antifungal agents, corticosteroids, and calcineurin inhibitors, offer symptomatic relief but have limitations in long-term use due to side effects and resistance issues. Chitosan exhibits excellent biocompatibility, biodegradability, and broad-spectrum antibacterial properties, making it a promising candidate for SD treatment. This review highlights chitosan's multifunctional properties such as antimicrobial, anti-inflammatory, sebum-regulating, and barrier-enhancing effects, which are closely related to the pathogenesis of SD. Additionally, the article summarizes the applications of chitosan in other skin conditions, including wound healing, infectious skin diseases, and atopic dermatitis, demonstrating its broad therapeutic potential. Through this comprehensive evaluation, the review aims to provide a theoretical foundation for clinical research on chitosan in SD and support the development of new, safer, and more effective treatment options for various skin conditions.

Unlocking disease insights to facilitate drug development: Pharmaceutical industry-academia collaborations in inflammation and immunology

Evolving research landscapes warrant updates in drug development strategy. Collaborations between pharmaceutical industry and academic institutions are crucial for accelerating drug development, leveraging individual expertise in clinical trial conduct and pathophysiological investigations. This review highlights key collaborations between Pfizer and academic institutions in inflammation and immunology research, including dermatology, gastroenterology, rheumatology, and autoimmunity. These collaborations harness and enhance the development of innovative disease models, large clinical databases, registries, and novel clinical trial designs, and open new avenues in disease management to improve patient outcomes.

Role of immune cells in seborrheic dermatitis: a two-sample bidirectional Mendelian randomization study

Prior research has indicated a link between seborrheic dermatitis (SD) and dysregulated immune responses; however, the causal linkage between this association and certain immune cell features has yet to be thoroughly clarified. This study seeks to examine the potential causal influence of immune cell characteristics on the pathogenesis of seborrheic dermatitis (SD) and to evaluate if these characteristics can function as biomarkers for early diagnosis and therapy. Data mining was performed using the Genome-Wide Association Study (GWAS) Catalog database to select 731 immune cell features for exposure variables and seborrheic dermatitis for the outcome variable in a forward Mendelian Randomization (MR) study. In a reverse MR analysis, seborrheic dermatitis was designated as the exposure factor, while the significant immune cell traits recognized by a forward MR analysis were used as outcome factors to exclude potential reverse causality. Five MR analyses were carried out by utilizing methods such as inverse variance weighting (IVW). Additionally, false discovery rate (FDR) correction, heterogeneity testing, level-dependent pleiotropy analysis, and sensitivity analysis were conducted. This study identified 11 immune traits causally associated with seborrheic dermatitis (SD). Specifically, five immune phenotypes were found to have been linking to a lower risk of SD: CD24on transitional, CD28 - DN(CD4 - CD8-)%T cell, CD45RA - CD28 - CD8br AC, Resting Treg%CD4, SSC - A on NKT. Conversely, six immunized traits have been shown with a greater risk of SD: CD127 - CD8br AC, CD20on CD24 + CD27+, CD27on IgD - CD38br, CD27on unsw mem, CD28 + DN(CD4 - CD8-)%T cell, HLA DR on CD33br HLA DR + CD14dim. The sensitivity analysis showed an absence of heterogeneity and level-dependent pleiotropy.This study demonstrates that specific immune cell traits not only correlate with SD but also provide valuable mechanistic insights into its pathogenesis. These immune traits also hold promise as biomarkers for early diagnosis, risk stratification, and personalized therapy. In addition, the findings provide new insights into immune mechanisms, highlighting the potential of targeted immunotherapies in SD treatment.

Global, regional, and national burden of seborrheic dermatitis in individuals aged 55 and older from 1990 to 2021: a trend analysis and future projections

Seborrheic dermatitis (SD), an inflammatory dermatosis, significantly lowers quality of life, particularly in the elderly. Although studies have focused on the burden of SD globally before, trends among people 55 and older have received less attention. Utilizing the data released in 2021 by the Global Burden of Disease (GBD) consortium, our research was conducted to evaluate the global, regional, and national burden of SD in adults over 55 between 1990 and 2021 through incidence, prevalence, and disability-adjusted life years (DALYs) alongside advanced methods such as joinpoint regression analysis. We also performed decomposition analysis to examine the contributions of population and epidemiological changes. Correlation analysis was used to explore the assocaition between Socio-demographic Index (SDI) /climate-related parameters and SD. The global incidence of SD among adults aged 55 and older markedly rose from 1990 to 2021. The incidence grew by 120.84%, the prevalence by 125.09%, and the DALYs rose by 124.25%. Higher burdens were observed in the high and high-middle SDI regions, whereas low SDI areas displayed the highest age-standardized rates. Environmental factors, particularly global warming, were strongly connected with the incidence and prevalence of SD. Future projections suggested continued increases in SD cases through 2040. This study highlights the increasing burden of SD among older adults, emphasizing the role of demographic and environmental factors. Targeted public health interventions addressing aging populations and climate-related risks are urgent to mitigate the impact of SD globally.

Tape-strip profiling identifies unique immune and lipid dysregulation in patients with seborrheic dermatitis

BACKGROUND

Seborrheic dermatitis (SD) is a common, chronic inflammatory skin disease with limited understanding of its pathophysiology. Molecular profiling has been limited by invasiveness of sampling methods.

OBJECTIVE

To analyze the molecular skin profile of adult patients with SD using tape strips.

METHODS

Tape-strips obtained from facial lesions of 26 adult SD patients and 18 demographically matched healthy controls were evaluated with RNA sequencing.

RESULTS

SD molecular skin fingerprint was characterized by strong and significant upregulation of interleukin (IL)23/T-helper (Th)17 and Th22 (i.e. IL23A, IL22, PI3, LL37, S100A8, S100A12), some Th1 skewing (OASL, STAT1, CXCL9), and limited Th2 modulation. A parallel downregulation of barrier markers (CLDN1/8, FA2H, ELOVL3) was also observed.

LIMITATIONS

Limited representation of mild and severe SD patients.

CONCLUSION

These data deepen our understanding of SD suggesting that it has robust Th17/Th22, some Th1 skewing, and minimal Th2 activation, and associated skin barrier alterations. This provides rationale for novel immunomodulatory treatment approaches for SD patients targeting IL23/Th17 and/or Th22 pathways.

Skin Microbiota: Mediator of Interactions Between Metabolic Disorders and Cutaneous Health and Disease

Metabolic disorders, including type 2 diabetes mellitus (T2DM), obesity, and metabolic syndrome, are systemic conditions that profoundly impact the skin microbiota, a dynamic community of bacteria, fungi, viruses, and mites essential for cutaneous health. Dysbiosis caused by metabolic dysfunction contributes to skin barrier disruption, immune dysregulation, and increased susceptibility to inflammatory skin diseases, including psoriasis, atopic dermatitis, and acne. For instance, hyperglycemia in T2DM leads to the formation of advanced glycation end products (AGEs), which bind to the receptor for AGEs (RAGE) on keratinocytes and immune cells, promoting oxidative stress and inflammation while facilitating Staphylococcus aureus colonization in atopic dermatitis. Similarly, obesity-induced dysregulation of sebaceous lipid composition increases saturated fatty acids, favoring pathogenic strains of Cutibacterium acnes, which produce inflammatory metabolites that exacerbate acne. Advances in metabolomics and microbiome sequencing have unveiled critical biomarkers, such as short-chain fatty acids and microbial signatures, predictive of therapeutic outcomes. For example, elevated butyrate levels in psoriasis have been associated with reduced Th17-mediated inflammation, while the presence of specific Lactobacillus strains has shown potential to modulate immune tolerance in atopic dermatitis. Furthermore, machine learning models are increasingly used to integrate multi-omics data, enabling personalized interventions. Emerging therapies, such as probiotics and postbiotics, aim to restore microbial diversity, while phage therapy selectively targets pathogenic bacteria like Staphylococcus aureus without disrupting beneficial flora. Clinical trials have demonstrated significant reductions in inflammatory lesions and improved quality-of-life metrics in patients receiving these microbiota-targeted treatments. This review synthesizes current evidence on the bidirectional interplay between metabolic disorders and skin microbiota, highlighting therapeutic implications and future directions. By addressing systemic metabolic dysfunction and microbiota-mediated pathways, precision strategies are paving the way for improved patient outcomes in dermatologic care.

The Relationship Between Nutrition Habits, BMI, Anxiety, and Seborrheic Dermatitis

BACKGROUND

Seborrheic dermatitis (SD) is a chronic, inflammatory disease characterized by unknown etiopathogenesis. It affects skin areas rich in sebaceous glands. There are strong data on the relationship between nutrition habits, body mass index (BMI), psychoemotional status, and sebaceous gland diseases such as acne, rosacea, and androgenetic alopecia. However, there are very little data on SD, nutrition habits, BMI, and psychoemotional status.

AIMS

We aimed to evaluate the nutrition habits, BMI, and psychoemotional status in patients with SD.

METHODS

One hundred patients with SD and 110 healthy controls aged 18-65 years were included. Adolescents Food Habits Checklist (AFHC), a questionnaire form consisting information about nutrition habits and Depression Anxiety Stress Scale-21 (DASS-21) were completed by the participants, and BMI was calculated.

RESULTS

Severity of SD was positively correlated with BMI (p = 0.018). Patients with SD consumed more bread and less fruits-vegetables (p = 0.001, p = 0.006). Margarine, animal fat, and sugar consumption was higher in patients with moderate to severe SD (p = 0.008, p = 0.050). AFHC score was lower in patients with SD (p = 0.009). DASS-21 anxiety subscale and DASS-21 total scores were higher in the moderate to severe SD group (p = 0.035, p = 0.049).

CONCLUSIONS

Nutrition habits, higher BMI, and psychoemotional status may play a critical role in the etiopathogenesis of SD. Healthy nutrition habits and psychoemotional status may prevent the occurrence and exacerbation of SD.

Is seborrhoeic dermatitis of infancy and childhood related to maternal history of seborrhoeic dermatitis? A large population-based cohort study from the UK

BACKGROUND

The pathophysiology of seborrhoeic dermatitis (SebD) is complex and is likely to be related to an interplay of the microbial colonization of the skin and local immunity. There are also genetic components to the illness. At least two forms of SebD exist, infantile (ISebD), which has onset early in life, and SebD with later onset.

OBJECTIVES

We aimed to improve our understanding of SebD by evaluating whether maternal history of SebD is associated with increased risk of ISebD or childhood-onset SebD (CSebD, with onset after 5 years of life).

METHODS

We performed a prospective cohort study of mother-child pairs using data from a large UK primary care electronic medical records database.

RESULTS

We analysed 1 023 140 children with linked maternal data. The mean (SD) time of follow-up for the children was 10.2 (7.9) years for a total follow-up of more than 10 million person-years. Proportional hazards models [HRs (95% confidence intervals)] were used to examine the association between presence of SebD in mothers and SebD in the child. Maternal history of SebD was associated with development of SebD [1.99 (1.91-2.09)], ISebD [1.86 (1.74-1.99)] and CSebD [2.12 (1.97-2.29)] in their children. However, ISebD in a child was not associated with that child later developing CSebD [0.91 (0.82-1.01)].

CONCLUSIONS

Maternal history of SebD is a risk factor for the development of SebD in children. While we cannot fully differentiate SebD risk due to mother's genetics (inheritance) from a newborn's environment, our results lend credence to the possible role of genetics in SebD. A child with ISebD does not appear to be at risk for developing CSebD.

Exploring the Impact of Vitamin D and Zinc Deficiencies on Seborrheic Dermatitis: A Comparative Study

Background and Aims

Seborrheic dermatitis (SD) is a chronic inflammatory skin condition that affects patients' quality of life. Emerging evidence suggests that vitamin and mineral deficiencies may contribute to its progression, although the exact etiology remains unclear.

Objective

This case-control study assessed the serum levels of vitamin D and zinc in SD patients compared to a healthy control group, with a focus on how these deficiencies relate to disease severity.

Methods

A total of 71 SD patients and 71 healthy controls participated, providing demographic data and blood samples. Disease severity was evaluated using the SEDASI scoring system. Serum vitamin D and zinc levels were measured using ELISA and photometric methods, respectively. Statistical analysis was performed using t-tests and chi-square tests in SPSS 24, with groups matched for demographic variables (p > 0.05).

Results

Findings revealed no significant difference in vitamin D levels between SD patients and the control group (p = 0.066). However, zinc levels were notably lower in the SD group (p = 0.001). Additionally, vitamin D levels were inversely related to the severity of SD (p = 0.022), while no correlation was found between zinc levels and disease severity (p = 0.664).

Conclusion

Zinc deficiency appears to play a role in SD pathogenesis, while lower vitamin D levels are associated with increased disease severity. These findings highlight the need for further research into the potential therapeutic role of nutrient supplementation in managing SD.

Perturbations in the skin microbiome of infantile and adult seborrheic dermatitis and new treatment options based on restoring a healthy skin microbiome

Seborrheic dermatitis (SD) is a common, multifaceted skin condition, but its undefined etiology hampers the development of effective therapeutic strategies. In this review, we describe the intricate relationship between the skin microbiome and the pathogenesis of SD, focusing on the complex interplay between three major groups of organisms that can either induce inflammation (Malassezia spp., Staphylococcus aureus) or else promote healthy skin (Propionibacterium spp.). We describe how the disequilibrium of these microorganisms in the skin microbiome can develop skin inflammation in SD patients. Understanding these complex interactions of the skin microbiome has led to development of novel probiotics (e.g., Vitreoscilla spp. and Lactobacillus spp.) to restore normal skin physiology in SD. There are also differences in the skin microbiomes of healthy and SD infant and adult patients that impact pathogenesis and prompt different management strategies. A deeper understanding of the skin microbiome and its dynamic interactions will provide valuable insights into the pathogenesis of SD and prompt further development of targeted probiotic treatments to restore the balance of the skin microbiome in SD patients.

Adult and infantile seborrheic dermatitis: update on current state of evidence and potential research frontiers

Seborrheic dermatitis (SD) is a highly prevalent dermatological condition globally. The condition demonstrates bimodal presentation with what is commonly thought to be two subtypes: adult/adolescent seborrheic dermatitis (ASD) and infantile seborrheic dermatitis (ISD). Despite the common prevalence of ASD and ISD, there remains uncertainty around the underlying pathogenetic mechanisms, risk factors, and appropriate classification of the disease(s). This narrative review summarizes the current understanding of the epidemiology, presentation, and pathogenetic factors like epidermal barrier dysfunction, lipid abnormalities, and cutaneous microbiome for ASD and ISD. Elements such as immune responsiveness, neuroendocrine factors, and genetics in these disease states are also investigated. Throughout our review, we highlight shared features and discrepancies between ASD and ISD that are present in the literature and discuss potential avenues for future research that explore these disease states. We aim to contribute to the medical discourse on ASD and ISD and increase awareness of the need for additional research around these conditions, ultimately informing better targeting of therapeutics moving forward.

Malassezia globosa Induces Differentiation of Pathogenic Th17 Cells by Inducing IL-23 Secretion by Keratinocytes

Malassezia, the most abundant fungal commensal on the mammalian skin, has been linked to several inflammatory skin diseases such as atopic dermatitis, seborrheic dermatitis and psoriasis. This study reveals that epicutaneous application with Malassezia globosa (M. globosa) triggers skin inflammation in mice. RNA-sequencing of the resulting mouse lesions indicates activation of Interleukin-17 (IL-17) signaling and T helper 17 (Th17) cells differentiation pathways by M. globosa. Furthermore, our findings demonstrate a significant upregulation of IL-23, IL-23R, IL-17A, and IL-22 expressions, along with an increase in the proportion of Th17 and pathogenic Th17 cells in mouse skin exposed to M. globosa. In vitro experiments illustrate that M. globosa prompts human primary keratinocytes to secrete IL-23 via TLR2/MyD88/NF-κB signaling. This IL-23 secretion by keratinocytes is shown to be adequate for inducing the differentiation of pathogenic Th17 cells in the skin. Overall, these results underscore the significant role of Malassezia in exacerbating skin inflammation by stimulating IL-23 secretion by keratinocytes and promoting the differentiation of pathogenic Th17 cells.

Ocular Manifestations in Seborrheic Dermatitis Epidemiology, Clinical Features, and Management: A Comprehensive Review

Seborrheic dermatitis (SD) often leads to ocular manifestations (OM) that are frequently overlooked. This study comprehensively explains the genesis of these ocular issues, which involves a combination of Malassezia overgrowth, changes in sebum production, and inflammatory responses in the body. The periocular region is rich in sebaceous glands, allowing Malassezia to thrive, which can lead to an inflammatory reaction that spreads to the eye surface, causing disorders such as blepharitis, conjunctivitis, keratitis, and ocular surface diseases. Although epidemiological data are limited, it is well established that ocular involvement occurs in approximately 10%-40% of individuals with SD. Early detection and treatment are crucial to prevent potential vision-threatening complications. A comprehensive diagnostic approach is necessary, including clinical examination, slit-lamp biomicroscopy, tear film analysis, and corneal imaging. Managing these conditions requires a multidisciplinary strategy involving collaboration between dermatologists and ophthalmologists. The treatment should involve topical and systemic medications to address the skin and ocular components. Patient education is critical for improving adherence to therapy, self-management, and the early identification of problems. In the future, it will be essential to investigate the intricate interactions between Malassezia species and host immunological processes. This collective effort will involve creating new biomarkers and diagnostic tools, investigating targeted immunomodulatory drugs and novel lipid-based medicines as potential treatments, and conducting large-scale longitudinal studies to understand the epidemiological patterns and prognostic variables better. By raising awareness, encouraging collaboration across disciplines, and advancing research, healthcare practitioners can significantly improve patients' quality of life with SD and OM.

An Assessment of the Safety, Efficacy, and Tolerability of a Novel Scalp Treatment Regimen Combining a Hydroxy Acid-Based Scrub and Copper Tripeptide Serum in the Management of Seborrheic Dermatitis in Adults

Background and objective Scalp dandruff, a prevalent dermatological condition marked by flaking and itching, affects a large segment of the population. Sun exposure, genetics, and dryness, along with winter conditions, indoor heating, and hard water, all contribute to moisture loss and scalp imbalance. This study aimed to evaluate the safety, efficacy, and tolerability of a novel regimen combining a scalp scrub with hydroxy acid derivatives for exfoliation and dandruff removal, and a serum containing copper tripeptide-1, witch hazel (Hamamelis virginiana), hesperidin, hyaluronic acid, and pea protein (Pisum sativum) for hydration and scalp health. Methods This prospective, interventional, open-label, single-center study assessed the safety, efficacy, and in-use tolerability of a scalp scrub and serum regimen for mild to moderate dandruff. Ethical approval was granted by ACEAS - Independent Ethics Committee and all participants provided written consent. The study evaluated changes in Adherent Scalp Flaking Score (ASFS), scalp hydration with the Corneometer® CM 825, hair thickness, hair density, and scalp condition using CASLite Nova. Scalp appearance and treatment usage perception were evaluated on day 1, day 8, and day 15. Statistical analysis was conducted using SPSS Statistics v29.0.1.0 (IBM Corp., Armonk, NY) and Microsoft Excel 2019, with results reported as p-values and 95% confidence intervals (CI). Results As per the ASFS scale for adherent scalp flaking, a significant improvement of 61.24% (p<0.0001) was observed by day 15. Assessments with CASLite Nova showed significant increases in hair density and hair thickness by 12.48% (p<0.0001) and 25.36% (p<0.0001), respectively. Regarding scalp condition, the proportion of individuals with a dry scalp and significant keratin decreased from 65.52% at baseline to 6.9% by day 15. The incidence of dry scalp with fine dandruff also decreased from 6.9% at baseline to 0% by day 15. Conversely, the percentage of individuals with a dry scalp and some keratin increased from 27.59% at baseline to 48.28% by day 15. Also, the proportion of subjects with a normal scalp, characterized by good hair density and thickness, increased from 0% at baseline to 44.83% by day 15. Scalp skin hydration, measured by Corneometer® CM 825, showed a significant improvement of 76.24% (p<0.0001) from baseline to day 15. Overall, there were notable enhancements in scalp appearance, with reductions in itchiness, redness, roughness, and scaliness. All subjects reported satisfaction with the treatment. Conclusions The ThriveCo scalp regimen (scalp scrub + serum) has been demonstrated to be both effective and safe in treating and reducing scalp dandruff in healthy adults. The regimen significantly reduced ASFS by effectively removing visible scalp flakes from day 1 to day 15 with continuous use. Furthermore, the kit improved overall scalp condition, increased skin hydration, and enhanced the scalp's appearance. The components include scalp scrub with hydroxy acid derivatives for exfoliation and dandruff removal, and a serum containing copper tripeptide-1, Hamamelis virginiana, hesperidin, hyaluronic acid, and pea protein (Pisum sativum) for hydration and overall scalp health over the 15-day treatment period. The synergistic effects of this regimen work to clear visible dandruff flakes, reduce adherent scalp flaking, rejuvenate the scalp, and simultaneously strengthen the hair.

Topically Applied Therapies for the Treatment of Skin Disease: Past, Present, and Future

The purpose of this review is to summarize essential biological, pharmaceutical, and clinical aspects in the field of topically applied medicines that may help scientists when trying to develop new topical medicines. After a brief history of topical drug delivery, a review of the structure and function of the skin and routes of drug absorption and their limitations is provided. The most prevalent diseases and current topical treatment approaches are then detailed, the organization of which reflects the key disease categories of autoimmune and inflammatory diseases, microbial infections, skin cancers, and genetic skin diseases. The complexity of topical product development through to large-scale manufacturing along with recommended risk mitigation approaches are then highlighted. As such topical treatments are applied externally, patient preferences along with the challenges they invoke are then described, and finally the future of this field of drug delivery is discussed, with an emphasis on areas that are more likely to yield significant improvements over the topical medicines in current use or would expand the range of medicines and diseases treatable by this route of administration. SIGNIFICANCE STATEMENT: This review of the key aspects of the skin and its associated diseases and current treatments along with the intricacies of topical formulation development should be helpful in making judicious decisions about the development of new or improved topical medicines. These aspects include the choices of the active ingredients, formulations, the target patient population's preferences, limitations, and the future with regard to new skin diseases and topical medicine approaches.

Ketoconazole Shampoo for Seborrheic Dermatitis of the Scalp: A Narrative Review

Seborrheic dermatitis (SD) is a common inflammatory skin condition characterized by itchy, sensitive patches of greasy, flaky skin in areas rich in sebaceous glands, such as the scalp. Cases range from asymptomatic to debilitating, with effective treatment in severe cases proving crucial to patient quality of life. Ketoconazole shampoo is a topical antifungal that is a promising treatment option for individuals affected by this condition.Numerous trials display significant improvement in irritation and scaling of scalp seborrheic dermatitis (SSD) with ketoconazole shampoo treatment. Most studies also report optimally low relapse rates as well as little to no side effects, including rare skin irritation that resolves with cessation of the drug. Based on these findings, ketoconazole shampoo seems to be a safe and effective treatment for SSD.The present investigation reviews knowledge and research regarding ketoconazole shampoo as a treatment for SSD for physician consideration in the clinical setting.

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.

Unveiling the mechanism of essential oil action against skin pathogens: from ancient wisdom to modern science

Essential oils are among the most well-known phyto-compounds, and since ancient times, they have been utilized in medicine. Over 100 essential oils have been identified and utilized as therapies for various skin infections and related ailments. While numerous commercial medicines are available in different dosage forms to treat skin diseases, the persisting issues include their side effects, toxicity, and low efficacy. As a result, researchers are seeking novel classes of compounds as substitutes for synthetic drugs, aiming for minimal side effects, no toxicity, and high efficacy. Essential oils have shown promising antimicrobial activity against skin-associated pathogens. This review presents essential knowledge and scientific information regarding essential oil's antimicrobial capabilities against microorganisms that cause skin infections. Essential oils mechanisms against different pathogens have also been explored. Many essential oils exhibit promising activity against various microbes, which has been qualitatively assessed using the agar disc diffusion experiment, followed by determining the minimum inhibitory concentration for quantitative evaluation. It has been observed that Staphylococcus aureus and Candida albicans have been extensively researched in the context of skin-related infections and their antimicrobial activity, including established modes of action. In contrast, other skin pathogens such as Staphylococcus epidermidis, Streptococcus pyogens, Propionibacterium acnes, and Malassezia furfur have received less attention or neglected. This review report provides an updated understanding of the mechanisms of action of various essential oils with antimicrobial properties. This review explores the anti-infectious activity and mode of action of essential against distinct skin pathogens. Such knowledge can be valuable in treating skin infections and related ailments.

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.

Pediatric Dermatitis Seborrhoica - A Clinical and Therapeutic Review

Pediatric dermatitis seborrhoica (DS) is a common inflammatory disorder of infancy and adolescence distinct from atopic dermatitis. We performed a narrative review on clinical and therapeutic aspects of the disease. The prevalence varies geographically and can reach up to 10%. There is a slight male predominance. Although etiopathology is not well known, both endogenous and exogenous factors contribute. Skin microbiome and its interaction with sebaceous gland function is crucial. The inflammatory pathways include innate immune function and skin barrier disturbances. Malassezia spp. and certain bacteria are increased in lesional skin. DS develops in different clinical subtypes, from localized cephalic to disseminated disease with a risk of erythroderma and eczema herpeticatum. Treatment consists of skin care and topical and rarely systemic medical therapy. Cornerstones of treatment are antifungals and mild corticosteroids. Targeted treatment is on the horizon. Pediatric DS is a common disorder important in the differential diagnosis of skin problems in infants and and children. Due to better understanding of its pathogenesis, new treatment options are developed.

Roflumilast foam 0.3% for adolescent and adult patients with seborrheic dermatitis: A randomized, double-blinded, vehicle-controlled, phase 3 trial

BACKGROUND

The topical phosphodiesterase 4 inhibitor roflumilast has been studied in several dermatologic conditions.

OBJECTIVE

Roflumilast foam 0.3% is being investigated as a topical treatment for seborrheic dermatitis (SD).

METHODS

In this phase 3, double-blinded trial, patients with SD were randomly assigned (2:1 ratio) to once-daily roflumilast foam 0.3% or vehicle foam for 8 weeks. The primary efficacy outcome was Investigator Global Assessment (IGA) Success at week 8, defined as IGA of 0 (Clear) or 1 (Almost Clear) plus ≥2-point improvement from baseline. Safety was also assessed.

RESULTS

79.5% of roflumilast-treated and 58.0% of vehicle-treated patients met the primary endpoint (P < .001); statistically significant differences in IGA Success also favored roflumilast at week 2 (roflumilast: 43.0%; vehicle: 25.7%; P < .001) and week 4 (roflumilast: 73.1%; vehicle: 47.1%; P < .001). Roflumilast was well-tolerated with a low rate of treatment-emergent adverse events.

LIMITATIONS

Study limitations include the 8-week treatment period for this chronic condition.

CONCLUSIONS

Once-daily roflumilast foam was superior to vehicle in leading to IGA of Clear or Almost Clear plus ≥2-point improvement from baseline at 8 weeks in patients with SD. Longer trials are needed to determine durability and safety of roflumilast foam in SD.

More yeast, more problems?: reevaluating the role of Malassezia in seborrheic dermatitis

Seborrheic dermatitis (SD) is an inflammatory skin disorder and eczema subtype increasingly recognized to be associated with significant physical, psychosocial, and financial burden. The full spectrum of SD, including dandruff localized to the scalp, is estimated to affect half of the world's population. Despite such high prevalence, the exact etiopathogenesis of SD remains unclear. Historically, many researchers have theorized a central, causative role of Malassezia spp. based on prior studies including the proliferation of Malassezia yeast on lesional skin of some SD patients and empiric clinical response to antifungal therapy. However, upon closer examination, many of these findings have not been reproducible nor consistent. Emerging data from novel, targeted anti-inflammatory therapeutics, as well as evidence from genome-wide association studies and murine models, should prompt a reevaluation of the popular yeast-centered hypothesis. Here, through focused review of the literature, including laboratory studies, clinical trials, and expert consensus, we examine and synthesize the data arguing for and against a primary role for Malassezia in SD. We propose an expansion of SD pathogenesis and suggest reframing our view of SD to be based primarily on dysregulation of the host immune system and skin epidermal barrier, like other eczemas.

Unmet needs for patients with seborrheic dermatitis

Seborrheic dermatitis (SD) is a common skin disease with signs and symptoms that may vary by skin color, associated medical conditions, environmental factors, and vehicle preference. Diagnosis of SD is based on presence of flaky, "greasy" patches, and/or thin plaques accompanied by erythema of the scalp, face, ears, chest, and groin and is associated with pruritus in many patients. The presentation may vary in different skin types and hyper- or hypopigmentation may occur, with or without erythema and minimal or no scaling. While the pathogenesis is not certain, 3 key factors generally agreed upon include lipid secretion by sebaceous glands, Malassezia spp. colonization, and some form of immunologic dysregulation that predisposes the patient to SD. Treatment involves reducing proliferation of, and inflammatory response to, Malassezia spp. Topical therapies, including antifungal agents and low potency corticosteroids, are the mainstay of treatment but may be limited by efficacy and side effects. Few novel treatments for SD are currently being studied; however, clinical trials assessing the use of topical phosphodiesterase-4 inhibitors have been completed. Improving outcomes in SD requires recognizing patient-specific manifestations/locations of the disease, including increased awareness of how it affects people of all skin types.

Microbiome: Role in Inflammatory Skin Diseases

As the body's largest organ, the skin harbors a highly diverse microbiota, playing a crucial role in resisting foreign pathogens, nurturing the immune system, and metabolizing natural products. The dysregulation of human skin microbiota is implicated in immune dysregulation and inflammatory responses. This review delineates the microbial alterations and immune dysregulation features in common Inflammatory Skin Diseases (ISDs) such as psoriasis, rosacea, atopic dermatitis(AD), seborrheic dermatitis(SD), diaper dermatitis(DD), and Malassezia folliculitis(MF).The skin microbiota, a complex and evolving community, undergoes changes in composition and function that can compromise the skin microbial barrier. These alterations induce water loss and abnormal lipid metabolism, contributing to the onset of ISDs. Additionally, microorganisms release toxins, like Staphylococcus aureus secreted α toxins and proteases, which may dissolve the stratum corneum, impairing skin barrier function and allowing entry into the bloodstream. Microbes entering the bloodstream activate molecular signals, leading to immune disorders and subsequent skin inflammatory responses. For instance, Malassezia stimulates dendritic cells(DCs) to release IL-12 and IL-23, differentiating into a Th17 cell population and producing proinflammatory mediators such as IL-17, IL-22, TNF-α, and IFN-α.This review offers new insights into the role of the human skin microbiota in ISDs, paving the way for future skin microbiome-specific targeted therapies.

Is seborrheic dermatitis associated with early-stage osteoarthritis?

Seborrheic dermatitis (SD) and osteoarthritis involve similar factors in their pathogenesis. Both of these diseases are associated with an increased frequency of metabolic syndrome and underlying systemic inflammation. This study evaluated the thickness of the distal femoral cartilage using ultrasonography in patients with SD. The study enrolled 60 patients with SD (19 females and 41 males, mean age: 34.07 ± 12.56 years) and 60 controls matched for age and sex (20 females and 40 males, mean age: 35.08 ± 12.78 years). Ultrasonography was used to measure the distal femoral cartilage thickness (FCT) of the right medial condyle, right lateral condyle, right intercondylar area, left medial condyle, left lateral condyle, and left intercondylar area. FCT values at all points were significantly higher in patients with SD than in the controls (P < .05). Further, all FCT values were significantly higher in patients with moderate SD than in those with mild SD (P < .001). A strong positive correlation was observed between disease severity and FCT measured at right medial condyle (r = .7, P < .001), right lateral condyle (r = .749, P < .001), right intercondylar area (r = .79, P < .001), left medial condyle (r = .624, P < .001), and left intercondylar area (r = .703, P < .001). Further, a moderately positive correlation was observed between disease severity and FCT measured at left lateral condyle (r = .581, P < .001). Increased FCT in patients with SD might be an early indicator of osteoarthritis. However, further studies, especially those evaluating older patients with SD, are required to support our findings.

The burden of dermatitis from 1990-2019 in the Middle East and North Africa region

BACKGROUND

There are several types of dermatitis, each capable of causing enduring changes that extend beyond physical discomfort. In severe cases, dermatitis can significantly affect mental health, social interactions, and the overall quality of life. This study reports the burden of dermatitis in the Middle East and North Africa (MENA) region from 1990 to 2019, according to sex, age category, and socio-demographic index (SDI).

METHODS

Publicly available data regarding the point prevalence, incidence, and years lived with disability (YLDs) were collected from the Global Burden of Disease 2019 study for both the MENA region and its constituent countries. The point prevalence, incidence, and YLDs of dermatitis were represented as counts and age-standardised rates with 95% uncertainty intervals (UIs).

RESULTS

In 2019, the age-standardised point prevalence of dermatitis was 2744.6 (2517.8-3003.1) per 100,000 population, which was 2.3% lower than in 1990. The YLD rate was 92.3 (55.6-143.4) per 100,000 population, which was 3.1% lower than in 1990. The largest point prevalence rates were observed among those aged 70-74, for both sexes. The 2019 MENA/Global DALY ratio was not above one in any age group for either sex. During the period 1990 to 2019, there was no clear correlation between the burden of dermatitis and the SDI level.

CONCLUSION

The dermatitis burden in the MENA region remained relatively stable from 1990 to 2019. Future prevention efforts should focus on improving healthcare access, health education, and workplace safety regulations.

Lesional skin of seborrheic dermatitis patients is characterized by skin barrier dysfunction and correlating alterations in the stratum corneum ceramide composition

Seborrheic dermatitis (SD) is a chronic inflammatory skin disease characterized by erythematous papulosquamous lesions in sebum rich areas such as the face and scalp. Its pathogenesis appears multifactorial with a disbalanced immune system, Malassezia driven microbial involvement and skin barrier perturbations. Microbial involvement has been well described in SD, but skin barrier involvement remains to be properly elucidated. To determine whether barrier impairment is a critical factor of inflammation in SD alongside microbial dysbiosis, a cross-sectional study was performed in 37 patients with mild-to-moderate facial SD. Their lesional and non-lesional skin was comprehensively and non-invasively assessed with standardized 2D-photography, optical coherence tomography (OCT), microbial profiling including Malassezia species identification, functional skin barrier assessments and ceramide profiling. The presence of inflammation was established through significant increases in erythema, epidermal thickness, vascularization and superficial roughness in lesional skin compared to non-lesional skin. Lesional skin showed a perturbed skin barrier with an underlying skewed ceramide subclass composition, impaired chain elongation and increased chain unsaturation. Changes in ceramide composition correlated with barrier impairment indicating interdependency of the functional barrier and ceramide composition. Lesional skin showed significantly increased Staphylococcus and decreased Cutibacterium abundances but similar Malassezia abundances and mycobial composition compared to non-lesional skin. Principal component analysis highlighted barrier properties as main discriminating features. To conclude, SD is associated with skin barrier dysfunction and changes in the ceramide composition. No significant differences in the abundance of Malassezia were observed. Restoring the cutaneous barrier might be a valid therapeutic approach in the treatment of facial SD.

Recent advances in understanding the role of the skin microbiome in the treatment of atopic dermatitis

The skin is the largest organ in the human body, and histologically consists of the epidermis, dermis and subcutaneous tissue. Humans maintain a cooperative symbiotic relationship with their skin microbiota, a complex community of bacteria, fungi and viruses that live on the surface of the skin, and which act as a barrier to protect the body from the inside and outside. The skin is a 'habitat' and vast 'ecosystem' inhabited by countless microbes; as such, relationships have been forged through millions of years of coevolution. It is not surprising then that microbes are key participants in shaping and maintaining essential physiological processes. In addition to maintaining barrier function, the unique symbiotic microbiota that colonizes the skin increases the immune response and provides protection against pathogenic microbes. This review examines our current understanding of skin microbes in shaping and enhancing the skin barrier, as well as skin microbiome-host interactions and their roles in skin diseases, such as atopic dermatitis (AD). We also report on the current status of AD therapeutic drugs that target the skin microbiome, related research on current therapeutic strategies, and the limitations and future considerations of skin microbiome research. In particular, as a future strategy, we discuss the need for a skin-on-a-chip-based microphysiological system research model amenable to biomimetic in vitro studies and human skin equivalent models, including skin appendages.

Seborrheic dermatitis-like adult tinea capitis due to Trichophyton rubrum in an elderly man

Adult tinea capitis is often neglected and misdiagnosed, especially in men. We herein reported an older man with seborrheic dermatitis-like tinea capitis caused by Trichophyton rubrum to raise awareness of the disease. Scale and alopecia were the critical diagnostic clues in this patient. Given the previous presence of tinea pedis and onychomycosis, relevant mycological examinations were promptly performed, and antifungal therapy, as well as patient education, were effectively administered.

Part 1: Understanding the role of Malassezia spp. in skin disorders: Malassezia yeasts as commensal or pathogenic organisms of human and animal skin

INTRODUCTION

Malassezia spp. are a group of lipid-dependent basidiomycetes yeasts acting as commensal organisms of the human and animal skin. However, under some not well-defined circumstances, these yeasts may switch to opportunistic pathogens triggering a number of skin disorders with different clinical presentations. The genus comprises of 18 lipid-dependent species with a variable distribution in the hosts and pathologies thus suggesting a host- and microbe-specific interactions.

AREA COVERED

This review highlighted and discussed the most recent literature regarding the genus Malassezia as a commensal or pathogenic organisms highlighting Malassezia-associated skin disorders in humans and animals and their antifungal susceptibility profile. A literature search of Malassezia associated skin disorders was performed via PubMed and Google scholar (up to May 2023), using the different keywords mainly associated with Malassezia skin disorders and Malassezia antifungal resistance.

EXPERT OPINION

Malassezia yeasts are part of the skin mycobiota and their life cycle is strictly associated with the environment in which they live. The biochemical, physiological, or immunological condition of the host skin selects Malassezia spp. or genotypes able to survive in a specific environment by changing their metabolisms, thus producing virulence factors or metabolites which can cause skin disorders with different clinical presentations.

First Use of Tapinarof Monotherapy for Seborrhoeic Dermatitis: A Case Report

Abstract is missing (Short communication)

Protective Effects of Naringenin and Apigenin in Ameliorating Skin Damage via Mediating the Nrf2 and NF-κB Pathways in Mice

Naringenin and apigenin are common flavonoids derived from edible plants with the potential to alleviate inflammation and improve skin antioxidation. This study aimed to evaluate the effects of naringenin and apigenin on oleic acid-induced skin damage in mice and compare their underlying mechanisms of action. Triglycerides and non-esterified fatty acids were significantly decreased by naringenin and apigenin, while apigenin intervention resulted in a better recovery of skin lesions. Naringenin and apigenin improved the antioxidative abilities of the skin by increasing catalase and total antioxidant capacity levels and decreasing malondialdehyde and lipid peroxide levels. The release of skin proinflammatory cytokines, such as interleukin (IL)-6, IL-1β, and tumor necrosis factor α, was inhibited after naringenin and apigenin pretreatments, but naringenin only promoted the excretion of IL-10. Additionally, naringenin and apigenin regulated antioxidant defense and inflammatory response by activating nuclear factor erythroid-2 related factor 2-dependent mechanisms and suppressing the expression of nuclear factor-kappa B. In summary, naringenin and apigenin are prospective ingredients that contribute to the amelioration of skin damage by activating anti-inflammatory and antioxidative responses.

Heat-killed Lacticaseibacillus paracasei GMNL-653 ameliorates human scalp health by regulating scalp microbiome

BACKGROUND

The equilibrium of the scalp microbiome is important for maintaining healthy scalp conditions, including sebum secretion, dandruff, and hair growth. Many different strategies to improve scalp health have been reported; however, the effect of postbiotics, such as heat-killed probiotics, on scalp health remains unclear. We examined the beneficial effects of heat-killed probiotics consisting of Lacticaseibacillus paracasei, GMNL-653, on scalp health.

RESULTS

Heat-killed GMNL-653 could co-aggregate with scalp commensal fungi, Malassezia furfur, in vitro, and the GMNL-653-derived lipoteichoic acid inhibited the biofilm formation of M. furfur on Hs68 fibroblast cells. The mRNA of hair follicle growth factors, including insulin-like growth factor-1 receptor (IGF-1R), vascular endothelial growth factor, IGF-1, and keratinocyte growth factor was up-regulated in skin-related human cell lines Hs68 and HaCaT after treatment with heat-killed GMNL-653. For clinical observations, we recruited 22 volunteer participants to use the shampoo containing the heat-killed GMNL-653 for 5 months and subsequently measured their scalp conditions, including sebum secretion, dandruff formation, and hair growth. We applied polymerase chain reaction (PCR) to detect the scalp microbiota of M. restricta, M. globosa, Cutibacterium acnes, and Staphylococcus epidermidis. A decrease in dandruff and oil secretion and an increase in hair growth in the human scalp were observed after the use of heat-killed GMNL-653-containing shampoo. The increased abundance of M. globosa and the decreased abundance of M. restricta and C. acnes were also observed. We further found that accumulated L. paracasei abundance was positively correlated with M. globosa abundance and negatively correlated with C. acnes abundance. S. epidermidis and C. acnes abundance was negatively correlated with M. globosa abundance and positively correlated with M. restricta. Meanwhile, M. globosa and M. restricta abundances were negatively associated with each other. C. acnes and S. epidermidis abundances were statistically positively correlated with sebum secretion and dandruff, respectively, in our shampoo clinical trial.

CONCLUSION

Our study provides a new strategy for human scalp health care using the heat-killed probiotics GMNL-653-containing shampoo. The mechanism may be correlated with the microbiota shift.

Lipid Alterations and Metabolism Disturbances in Selected Inflammatory Skin Diseases

Lipidomics is a term used to define the field that analyzes the structure, functions, and interactions of lipids. Inflammatory dermatoses and lipid disturbances are interrelated, especially due to chronic inflammatory conditions. This review discusses lipidomics in selected inflammatory skin diseases: psoriasis, lichen planus, and atopic dermatitis, as well as the less commonly mentioned hidradenitis suppurativa, rosacea, and acne vulgaris. Lipid homeostasis disorders are common; they are especially well-documented in psoriasis, lichen planus, and atopic dermatitis. Future studies are required for better insight into this issue, particularly on the skin lipidome. Understanding lipidomics, in particular skin diseases, increases our knowledge about their pathogenesis, and may become useful in adjusting tailored management for each patient as well establishing prognosis. Noteworthily, it seems advisable to alert doctors to the need to analyze lipid parameters and the complications of abnormal lipid metabolism in dermatological patients, which could decrease their comorbidities and improve the life quality and health condition of dermatological patients.

Evaluation of the effectiveness of triamcinolone solution diluted with normal saline for the treatment of seborrheic dermatitis

Background and Aim

Seborrheic dermatitis is a common inflammatory disease for which various treatments have been proposed. The main purpose of this study was to determine the effectiveness of 80-mg Triamcinolone solution diluted with 0.1% normal saline for the treatment of seborrheic dermatitis in adults.

Methods

For this study, 120 patients with seborrheic dermatitis were considered. After obtaining written and informed consent, patients were treated with 80 mg of Triamcinolone diluted with 0.1% normal saline. To evaluate the effectiveness of Triamcinolone treatment, the scoring index (SI) and the level of patient satisfaction were evaluated at 2 and 4 weeks after the start of treatment and also 4 weeks after the end of treatment.

Results

The results of the study showed that 61.67% (74 patients) were satisfied with "good" to "very good" for the Triamcinolone treatment to seborrheic dermatitis. Based on the findings of the study, it was found that the SI before treatment was equal to 2.45 ± 7.45, which after 2 weeks after treatment, this index decreased by 61.6% (SI: 2.86 ± 1.94). In addition, the SI decreased to 88.6% (SI: 0.85 ± 1.02) after 4 weeks.

Conclusion

Considering the high decrease in SI, increasing patient satisfaction and observing a low number of cases with recurrence of the disease by Triamcinolone treatment method, it can be concluded that injection of Triamcinolone 80 mg diluted with 0.1% normal saline can be effective and efficient for the treatment of seborrheic dermatitis.

Human leukocyte antigen system associations in Malassezia-related skin diseases

BACKGROUND

The human leukocyte antigen system (HLA) is divided into two classes involved in antigen presentation: class I presenting intracellular antigens and class II presenting extracellular antigens. While susceptibility to infections is correlated with the HLA system, data on associations between HLA genotypes and Malassezia-related skin diseases (MRSD) are lacking. Thus, the objective of this study was to investigate associations between HLA alleles and MRSD.

MATERIALS AND METHODS

Participants in The Danish Blood Donor Study (2010-2018) provided questionnaire data on life style, anthropometric measures, and registry data on filled prescriptions. Genotyping was done using Illumina Infinium Global Screening Array, and HLA alleles were imputed using the HIBAG algorithm. Cases and controls were defined using filled prescriptions on topical ketoconazole 2% as a proxy of MRSD. Logistic regressions assessed associations between HLA alleles and MRSD adjusted for confounders and Bonferroni corrected for multiple tests.

RESULTS

A total of 9455 participants were considered MRSD cases and 24,144 participants as controls. We identified four risk alleles B*57:01, OR 1.19 (95% CI: 1.09-1.31), C*01:02, OR 1.19 (95% CI: 1.08-1.32), C*06:02, OR 1.14 (95% CI: 1.08-1.22), and DRB1*01:01, OR 1.10 (95% CI: 1.04-1.17), and two protective alleles, DQB1*02:01, OR 0.89 (95% CI: 0.85-0.94), and DRB1*03:01, OR 0.89 (95% CI: 0.85-0.94).

CONCLUSION

Five novel associations between HLA alleles and MRSD were identified in our cohort, and one previous association was confirmed. Future studies should assess the correlation between Malassezia antigens and antigen-binding properties of the associated HLA alleles.

Investigation of the relationship between inflammatory blood parameters and seborrheic dermatitis

OBJECTIVE

Seborrheic dermatitis (SD) is a chronic inflammatory disease. The etiology of the disease is still unknown. The systemic immune-inflammation index (SII), red cell distribution width (RDW), mean platelet volume (MPV), C-reactive protein (CRP), monocyte to HDL cholesterol ratio (MHR), platelet to lymphocyte ratio (PLR), and neutrophil to lymphocyte ratio (NLR) have all been reported as inflammatory markers in recent studies. However, these inflammatory markers have not been explored in SD patients. This study aimed to explore inflammatory and hematological parameters in SD patients with healthy controls (HCs) and evaluate their possible relationship with disease severity.

MATERIALS AND METHODS

One hundred patients who presented to our hospital were diagnosed with SD and 74 HCs were retrospectively included in our study. The seborrheic dermatitis area severity index (SDASI) score was used to assess the severity of the SD.

RESULTS

The patient group's mean PLR, MPV ve CRP levels were statistically significantly higher than the HCs (p < 0.05). There was no statistically significant difference in the patients compared with the control group regarding RDW, NLR, MHR, and SII levels (p > 0.05). There was no statistically significant correlation between NLR, PLR, MPV, monocyte/HDL cholesterol, SII levels with age, and SDASI in the patient group. There was a significant correlation between CRP with age and RDW with SDASI score.

CONCLUSION

Hematological parameters and CRP are low-cost tests. These tests can be used to define inflammation levels in inflammatory diseases. This study shows that PLR, CRP, and MPV may be used as novel inflammatory markers in SD.

A Meta-Analysis on the Effectiveness of Sertaconazole 2% Cream Compared with Other Topical Therapies for Seborrheic Dermatitis

Seborrheic dermatitis (SD) is a relapsing inflammatory skin disorder that affects the seborrheic areas of the body. Its etiology is not completely elucidated; however, the link between disease exacerbations and the proliferation of Malassezia spp., along with the good response to antifungal agents, indicate the role of fungi in its pathophysiology. Sertaconazole nitrate is a relatively new imidazole antifungal agent with a particular structure, consisting in a benzothiophene ring similar to the indole ring of tryptophan, and it acts mainly through the inhibition of ergosterol synthesis and the formation of pores in the fungal cell membrane. The aim of our study was to evaluate the efficiency of sertaconazole 2% cream compared with other topical treatments in patients with SD. We performed an extensive literature search by browsing the PubMed database with the keyword combination “sertaconazole AND seborrheic dermatitis AND clinical trial”, which retrieved eight controlled clinical trials evaluating the effects of sertaconazole in SD. All of the clinical trials included a standard scoring index (SI). At 28 days since the beginning of the treatment, the sertaconazole regimen was associated with a significantly higher percentage of patients with mild SI and a lower percentage of patients with moderate or severe SI (odds ratio 0.51) than the other investigated treatments—hydrocortisone, ketoconazole, clotrimazole, metronidazole, pimecrolimus, and tacrolimus (odds ratio 1.95). In conclusion, treatment with sertaconazole 2% cream may represent an efficient alternative therapy for patients with SD.

Impact of seborrheic dermatitis on osteoporosis risk: A population‐based cohort study

Osteoporosis is a systemic bone-resorbing disease that easily causes subsequent risk of fracture. Hence, the substantial physical burden of osteoporosis makes it an important public health issue. Seborrheic dermatitis (SD) is a chronic, recurrent, inflammatory skin disease. Despite the advances in medication for treating osteoporosis, identifying undiagnosed osteoporosis patients is still challenging. Since osteoporosis and SD share a similar pathobiology, e.g. inflammation and hormonal imbalance, we aimed to investigate whether the existence of SD increases osteoporosis risk by using the Taiwan National Health Insurance Research Database. A total of 7831 patients aged 18-50 years with SD and a control group of 31 324 patients without SD matched by age, gender, Charlson Comorbidity Index, and index date at a ratio of 1:4 during 1996-2010 were recruited in the study. To measure the cumulative incidence and compare the hazard ratios of osteoporosis between each group, the Kaplan-Meier method and Cox proportional hazard regression models were utilized. It was found that 0.98% of SD patients had osteoporosis. Compared to the non-SD group, the SD group had a 5.95-fold higher osteoporosis risk after adjustment for variables. The impact of SD on osteoporosis risk was largest in the female and young age groups. In addition, the presence of hyperlipidemia, hyperthyroidism, and epilepsy synergistically increased osteoporosis incidence in the SD group. This first large cohort study demonstrated an association between SD and osteoporosis. Since the effect on bone health in SD patients with concomitant diseases is largest in early life, diet or lifestyle recommendations as well as regular bone examinations are advised during follow-up of SD.

Examination of Cutaneous Changes Among Patients Following SARS-CoV-2 Infection

Individuals infected with SARS-CoV-2 have been found to develop a variety of cutaneous symptoms. This study sought to describe varying cutaneous manifestations of COVID-19 in individuals presenting to an inpatient healthcare facility. We screened individuals who presented with COVID-19 for skin changes throughout the illness and administered a survey regarding demographics, medical history, and their cutaneous findings. Three individuals reported varying skin findings including wheals, petechiae, ecchymosis, and papules. One individual reported a worsening skin condition, psoriasis, as well as a new skin condition, seborrheic dermatitis. In conclusion, cutaneous manifestations of patients suffering from COVID-19 are wide-ranging and worsening skin conditions amongst these patients should be further investigated.

Microbiota-Independent Spontaneous Dermatitis Associated With Increased Sebaceous Lipid Production in Tmem79-Deficient Mice

TMEM79 is a predisposing gene for atopic dermatitis (AD). Tmem79-deficient mice develop spontaneous dermatitis in a biphasic pattern. The 1^st-phase dermatitis is unique, as it occurs independent of microbiota status, whereas the 2^nd-phase dermatitis is microbiota-dependent. In this study, we sought to identify key factors mediating the development of 1^st-phase dermatitis. Structural analysis showed that sebaceous gland hyperplasia started from 1^st-phase dermatitis. Longitudinal RNA-sequencing analysis revealed significant activation of fatty acid lipid-metabolism pathways in 1^st-phase dermatitis, whereas Th17-based immune response genes were highly expressed in 2^nd-phase dermatitis. Quantitative reverse transcription-polymerase chain reaction analysis revealed that genes involved in fatty acid elongation and sebocyte differentiation were upregulated in 1^st-phase dermatitis. The results of thin-layer chromatography supported these findings with an increased abundance of wax esters, cholesterol esters, and fatty alcohols in hair lipids. Further gas chromatography-tandem mass spectrometry analysis showed an increase in total fatty acid production, including that of elongated C20-24 saturated and C18-24 mono-unsaturated fatty acids. Collectively, these results suggest that aberrant production of sebaceous long-chain fatty acids is associated with microbiota-independent dermatitis. Further investigation of Tmem79-deficient mice may clarify the role of certain fatty acids in dermatitis.

Seborrheic Dermatitis in Older Adults: Pathogenesis and Treatment Options

Seborrheic dermatitis is a common and chronic skin disease, which is particularly prevalent in older adults. While a specific cause of seborrheic dermatitis remains largely unelucidated, the currently understood pathogenesis of seborrheic dermatitis revolves around the presence of Malassezia yeast colonies and an inflammatory response in the affected individual. Keratinocyte proliferation resulting from inflammasome response in the host skin leads to the clinically relevant symptoms of seborrheic dermatitis. The increasing number of older adults as a percentage of the population in the USA will lead to an even higher prevalence of the disease in the ensuing decades. Fortunately, there are multiple treatment options based on individual patient situations and preferences. Topical treatment is the gold standard, but oral therapy may be required in certain cases. In order to maximize effectiveness and minimize adverse pharmacologic effects, effective treatment for older adults must take into account changes in lifestyle and metabolism that occur with aging.