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.

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.

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.

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.

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.

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.

Dermatologic Conditions in Down Syndrome: A Multi-Site Retrospective Review of International Classification of Diseases Codes.

BACKGROUND AND OBJECTIVE: As the population and life expectancy of people with Down syndrome increases, identifying common skin conditions throughout the lifespan will help inform clinical care and research. We sought to evaluate dermatologic conditions diagnosed in pediatric and adult patients with Down syndrome. METHODS: This multicenter retrospective study analyzed demographic and outpatient visit International Classification of Diseases codes of patients with Down syndrome evaluated at outpatient dermatology clinics in the United States or Canada between 2011 and 2021. RESULTS: A total of 1529 patients with Down syndrome were identified from eight academic medical centers: 50.8% were children (0-12 years), 25.2% were adolescents (13-17 years), and 24% were adults (18 years and older). Eczematous dermatitis was the most common diagnosis overall (26%), followed by folliculitis (19.3%) and seborrheic dermatitis (15.6%). Other notable diagnoses included dermatophyte infections (13%), alopecia areata (11.6%), and psoriasis (6.7%). About 4.3% of visits included a code for high-risk medication use. Eczematous dermatitis, alopecia areata, and folliculitis were the most common diagnoses observed in children; folliculitis, hidradenitis suppurativa, and eczematous dermatitis in adolescents; and seborrheic dermatitis, eczematous dermatitis, and folliculitis in adults. CONCLUSIONS: Dermatologic conditions in patients with Down syndrome vary by age, but are most often eczematous, adnexal, and cutaneous autoimmune disorders. This multicenter retrospective review identifies skin diseases that should be prioritized for clinical care guideline development and research in the Down syndrome community.

New factors affecting wound healing and recurrence after pilonidal sinus surgery in adolescents; seborrheic dermatitis and psychiatric co-occurring conditions.

Postoperative wound healing problems and recurrence remain common for pilonidal sinus disease (PSD). Our study aimed to examine the effect of comorbidities in addition to the classic known factors that may affect wound complications and recurrence after PSD surgery. We retrospectively analysed 282 adolescent patients operated on in our clinic between 2014 and 2021. We gathered the postoperative wound healing patterns of the patients under four groups. With a mean age of 15.49 ± 1.45, 59.9% (n = 169) were male, 40.1% (n = 113) were female and 23.8% (n = 67) had recurrence. When examined according to the wound healing groups, 53.5% (n = 151) had an uneventful wound, 22.6% (n = 64) had prolonged wound care, 17.7% (n = 50) of the postoperative wounds did not close and had a recurrence and 6% (n = 17) had recurrence after the wound was healed. The number of sinuses, abscess presentation and the incidence of comorbid disease in group 1 were found to be statistically significantly lower than all other groups. Seborrheic dermatitis, obesity and psychiatric diagnoses showed high statistical association with group 3 and acne with group 4. In patients with seborrheic dermatitis or psychiatric diagnosis, a significant correlation was found between wound healing according to the type of surgery (p < 0.05). The wound healing patterns of these patients after total excision and primary closure surgeries were included in Group 3 with a statistically significant high rate. As two new factors, the significance of the presence of seborrheic dermatitis and psychiatric comorbidities should be evaluated in these patients whose wounds remain open postoperatively and do not respond to primary wound care and eventually relapse. Further histologic and pathologic investigations are needed for seborrheic dermatitis and PSD relation. Awareness of these diseases may change the decision of the type of surgery, and their treatment within the same time may support wound healing and ultimately reduce recurrence.

A folliculocentric perspective of dandruff pathogenesis: Could a troublesome condition be caused by changes to a natural secretory mechanism?

Dandruff is a common scalp condition, which frequently causes psychological distress in those affected. Dandruff is considered to be caused by an interplay of several factors. However, the pathogenesis of dandruff remains under-investigated, especially with respect to the contribution of the hair follicle. As the hair follicle exhibits unique immune-modulatory properties, including the creation of an immunoinhibitory, immune-privileged milieu, we propose a novel hypothesis taking into account the role of the hair follicle. We hypothesize that the changes and imbalance of yeast and bacterial species, along with increasing proinflammatory sebum by-products, leads to the activation of immune response and inflammation. Hair follicle keratinocytes may then detect these changes in scalp microbiota resulting in the recruitment of leukocytes to the inflammation site. These changes in the scalp skin immune-microenvironment may impact hair follicle immune privilege status, which opens new avenues into exploring the role of the hair follicle in dandruff pathogenesis. Also see the video abstract here: https://youtu.be/mEZEznCYtNs.

Evaluation of the effect of botulinum toxin injection in aggravating or improving seborrheic dermatitis symptoms: A prospective, single-arm clinical trial.

INTRODUCTION: Considering the proven therapeutic effect of botulinum toxin and the pathophysiology of seborrheic dermatitis, conflicting hypotheses have been put forward regarding the effect of injection of this toxin on the improvement or exacerbation of seborrheic dermatitis. Because of the lack of consistent studies investigating this relationship, we decided to conduct this study to investigate the effect of local botulinum toxin injection on sebum production and improvement or worsening of seborrheic dermatitis lesions. METHOD: This study was a prospective, single-arm clinical trial that involved the injection of botulinum toxin into 20 patients with complaints of skin wrinkles and simultaneous symptoms of seborrheic dermatitis. The trial was conducted at a dermatology clinic between March 2019 and March 2021. Two important characteristics of these patients were seborrheic dermatitis on the face or scalp and a referral for botulinum toxin injection to remove facial wrinkles. The Seborrheic Dermatitis Area and Severity Index (SDASI) was used to determine the severity of symptoms. RESULTS: In study of 20 patients with an average age of 40 years, despite the decrease in the average scores of all examined criteria of seborrheic dermatitis symptoms in study, 1 month after botulinum toxin injection, no significant effect of using this toxin was seen on the improvement of patients' symptoms (p value >0.05). CONCLUSION: Despite the emphasis of many studies on the effectiveness of botulinum toxin in reducing the activity of sebaceous glands, the use of botulinum toxin as a therapeutic modality for control the symptoms of seborrheic dermatitis is not suggested by this study. Conducting studies in which the location and technique of injection and the follow-up intervals of patients in them are based on the standard of other studies, are the suggestions made by comparing the results and method of the current study with other studies.

Treatment with the Topical Antimicrobial Peptide Omiganan in Mild-to-Moderate Facial Seborrheic Dermatitis versus Ketoconazole and Placebo: Results of a Randomized Controlled Proof-of-Concept Trial.

Facial seborrheic dermatitis (SD) is an inflammatory skin disease characterized by erythematous and scaly lesions on the skin with high sebaceous gland activity. The yeast Malassezia is regarded as a key pathogenic driver in this disease, but increased Staphylococcus abundances and barrier dysfunction are implicated as well. Here, we evaluated the antimicrobial peptide omiganan as a treatment for SD since it has shown both antifungal and antibacterial activity. A randomized, patient- and evaluator-blinded trial was performed comparing the four-week, twice daily topical administration of omiganan 1.75%, the comparator ketoconazole 2.00%, and placebo in patients with mild-to-moderate facial SD. Safety was monitored, and efficacy was determined by clinical scoring complemented with imaging. Microbial profiling was performed, and barrier integrity was assessed by trans-epidermal water loss and ceramide lipidomics. Omiganan was safe and well tolerated but did not result in a significant clinical improvement of SD, nor did it affect other biomarkers, compared to the placebo. Ketoconazole significantly reduced the disease severity compared to the placebo, with reduced Malassezia abundances, increased microbial diversity, restored skin barrier function, and decreased short-chain ceramide Cer[NSc34]. No significant decreases in Staphylococcus abundances were observed compared to the placebo. Omiganan is well tolerated but not efficacious in the treatment of facial SD. Previously established antimicrobial and antifungal properties of omiganan could not be demonstrated. Our multimodal characterization of the response to ketoconazole has reaffirmed previous insights into its mechanism of action.

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.

Clinical efficacy of a gentle anti-dandruff itch-relieving shampoo formulation.

Dandruff is a common scalp condition affecting almost half of the world's population. Despite its high prevalence, the exact pathophysiology is not well established and is understood to be multifactorial, with factors such as fungal colonization, sebaceous gland activity and individual factors being implicated. There is a need for an effective and safe shampoo that can target the above factors. Hence, we have developed a shampoo formulation with properties of oil control, moisturizing, non-irritative, anti-fungal, anti-microbial and itch-relieving. In this interventional, open-label study, we evaluated the efficacy and safety of this shampoo in reducing the clinical signs of dandruff and pruritus in patients with pre-existing mild-to-moderate dandruff over a course of 21-day treatment duration through self-assessment and objective clinical evaluations. After continued use of the shampoo, there was a significant decrease in the adherent and loose scalp flaking scores. Mean pruritus scores also decreased significantly across the 21-day time points. There were also no adverse events or skin intolerances reported. This study showed that our shampoo formulation has led to a significant reduction in both adherent and loose scalp flaking and pruritus when used in individuals suffering from mild to moderate dandruff. As such, it is an ideal shampoo, which can be used to effectively control dandruff.

Les pellicules sont une affection courante du cuir chevelu qui touche près de la moitié de la population mondiale. Malgré sa prévalence élevée, la physiopathologie exacte n'est pas bien établie et est comprise comme étant multifactorielle, avec des facteurs impliqués tels que la colonisation fongique, l'activité des glandes sébacées et des facteurs individuels. Un shampooing sûr et efficace pouvant cibler les facteurs évoqués ci-dessus est nécessaire. Par conséquent, nous avons développé une formulation de shampooing présentant des propriétés de contrôle du sébum, d'hydratation, non irritante, antifongique, antimicrobienne et de soulagement des démangeaisons. Dans cette essaie interventionnelle ouvert, nous avons évalué l'efficacité et la sécurité d'emploi de ce shampooing dans la réduction des signes cliniques de pellicules et de prurit chez des patients présentant des pellicules préexistantes légères à modérées sur une durée de traitement de 21 jours par le biais d'auto-évaluations et d'évaluations cliniques objectives. Après une utilisation continue du shampooing, une diminution significative des scores de squames adhérents et d'excoriation du cuir chevelu a été observée. Les scores de prurit moyens ont également significativement diminué tout au long de la période de 21 jours. De même, aucun événement indésirable ou intolérance cutanée n'a été rapporté. Cette étude a montré que notre formulation de shampooing a entraîné une réduction significative des squames adhérents, de l'excoriation du cuir chevelu et du prurit lorsqu'elle est utilisée chez des personnes souffrant de pellicules légères ou modérées. Il s'agit donc d'un shampooing idéal qui peut être utilisé pour contrôler efficacement les pellicules.

Enhanced piroctone olamine retention from shampoo for superior anti-dandruff efficacy.

BACKGROUND: Dandruff is a pervasive chronic condition which negatively impacts quality of life. Effective treatment requires efficient delivery of scalp benefit agents that control commensal scalp Malassezia levels. Delivery of benefit agents from shampoos requires balancing many technical parameters to achieve the desired outcome without sacrificing secondary parameters, such as cosmetic attributes. AIM: To develop formulation technologies that increase the shampoo delivery efficiency of the scalp benefit agent piroctone olamine (PO). Increased delivery should result in increased anti-dandruff efficacy. METHODS: Micellar Stability and Association parameters were quantified via dynamic surface tension and nuclear magnetic resonance (NMR) diffusion parameters, respectively. PO delivery has been assessed in vivo both on the scalp surface and follicular infindibula using extraction procedures and analytical analysis. Clinical anti-dandruff efficacy was assessed for an advanced delivery technology prototype in comparison to standard delivery technology. RESULTS: Shampoo prototypes have been developed that increase the delivery efficiency of PO. Both surfactant and polymer coacervate-based approaches have been developed. Decreased micellar stability results in weaker association between PO and micelles, resulting in more efficient PO retention on the scalp surface and delivery to the infundibula. Increased charge density of cationic polymers optimizes coacervation enabling improved PO delivery as well. Increased PO delivery has been shown clinically to result in higher anti-dandruff efficacy as measured by both visible flakes and underlying biomarkers. CONCLUSION: Increased efficiency PO delivery shampoos have been developed by optimization of both surfactant and coacervate parameters. The increased deposition efficiency results in significantly more products with significantly greater anti-dandruff efficacy.

CONTEXTE: Les pellicules sont une maladie chronique omniprésente qui a un impact négatif sur la qualité de vie. Un traitement efficace nécessite une administration efficace d'agents bénéfiques pour le cuir chevelu qui contrôlent les niveaux commensaux de Malassezia. L'administration d'agents bénéfiques à partir de shampooings nécessite d'équilibrer de nombreux paramètres techniques pour obtenir le résultat souhaité sans sacrifier des paramètres secondaires tels que les attributs cosmétiques. BUT: Développer des technologies de formulation qui augmentent l'efficacité d'administration du shampooing de l'agent bénéfique pour le cuir chevelu piroctone olamine (PO). Une livraison accrue devrait entraîner une efficacité antipelliculaire accrue. MÉTHODES: La stabilité micellaire et les paramètres d'association ont été quantifiés via les paramètres de tension superficielle dynamique et de diffusion RMN, respectivement. L'administration de PO a été évaluée in vivo à la fois sur la surface du cuir chevelu et sur l'indibula folliculaire à l'aide de procédures d'extraction et d'analyses analytiques. L'efficacité antipelliculaire clinique a été évaluée pour un prototype de technologie d'administration avancée par rapport à la technologie d'administration standard. RÉSULTATS: Des prototypes de shampooing ont été développés pour augmenter l'efficacité de livraison des PO. Des approches à base de tensioactifs et de coacervats polymères ont été développées. Une diminution de la stabilité micellaire entraîne une association plus faible entre le PO et les micelles, ce qui entraîne une rétention plus efficace du PO sur la surface du cuir chevelu et une livraison à l'infundibula. L'augmentation de la densité de charge des polymères cationiques optimise la coacervation, permettant également une meilleure administration de PO. Il a été démontré cliniquement que l'augmentation de l'administration de PO entraîne une efficacité antipelliculaire plus élevée, mesurée à la fois par les squames visibles et les biomarqueurs sous-jacents. CONCLUSION: Des shampooings à libération de PO à efficacité accrue ont été développés en optimisant à la fois les paramètres du tensioactif et du coacervat. L'efficacité de dépôt accrue se traduit par beaucoup plus de produits avec une efficacité antipelliculaire nettement supérieure.

MALASSEZIA COLONIZATION CORRELATES WITH THE SEVERITY OF SEBORRHEIC DERMATITIS.

OBJECTIVE: The aim: To compare the number of fungi of the genus Malassezia on inflated and healthy areas of the skin and to correlate them with the severity of seborrheic dermatitis. PATIENTS AND METHODS: Materials and methods: 168 patients with typical manifestations of seborrheic dermatitis on the scalp and face and 30 healthy individuals were recruited. SD severity was assessed by SEDASI. Samples from lesions on scalp, face and intact chest skin were cultivated and/or stained with methylene blue or cotton and inoculated onto Malassezia Leeming & Notman Agar Modified (MLNA). RESULTS: Results: A statistical difference in colonization intensity between all body zones (Dwass-Steel-Critchlow-Flinger pairwise comparisons p≤0,001). Face zone with lesions of SD patients was two times more colonized with funguses than in the control group (38,5 vs 16,5 p=0,003). The sternal area with no skin lesions was more colonized in the SD group (25,0 vs 9,0 p=0,013). The SEDASI was positively correlated with the amount of CFU on the face (Spearman's rho 0,849; p≤0,001) and trunk (0,714; p≤0,001). CONCLUSION: Conclusions: Our results demonstrate that inflamed seborrheic areas are more colonized with Malassezia fungi than intact areas. The intensity of Malassezia growth is correlated with the severity of the symptoms of seborrheic dermatitis. The level of colonization may be a potential biomarker to indicate the efficiency of new treatment approaches.

Relationship between scalp histamine levels and dandruff within an Indian population: A confirmation study using LC/MS/MS method.

Dandruff is a common and challenging complaint associated with type of scalp, skin and population. Scalp seborrheic dermatitis (SD) is a more severe manifestation of dandruff associated with very severe itching and inflammation. Histamine is an interesting biomarker released in scalp affected by dandruff and SD even though the mechanism is not well understood yet. A monocentre clinical study was conducted to confirm the relationship between dandruff/SD and scalp histamine level in an Indian population. Highly sensitive liquid chromatography coupled with mass spectrometry was used for histamine quantification in scalp from samples obtained non-invasively. Results showed that scalps with dandruff and mild to moderate SD had higher histamine levels compared with healthy scalps.

Analysis of cutaneous bacterial microbiota of Thai patients with seborrheic dermatitis.

Seborrheic dermatitis (SD) is a chronic inflammatory skin condition that occurs in body areas that contain profuse sebaceous glands. Skin microbiota are diverse across ethnic groups and its dysbiosis has been implicated in the pathogenesis of SD. Here, we reported the contribution of cutaneous bacterial microbiota to SD in the Thai population. Healthy individuals and patients with scalp SD were recruited into the study. Normal skin, scalp skin lesion (SL) and non-lesion sites (SNL) samples were collected using a tape stripping method and next-generation sequencing of 16S rRNA for microbiome analysis. Although bacterial diversity in all sample groups was not statistically different, a population of bacteria commonly found on skin of scalp showed signs of dysbiosis. Apart from the reduction of Corynebacterium spp., SD-specific microbiota was dominated by Firmicutes at taxa level and Pseudomonas spp., Staphylococcus spp. and Micrococcus spp. at genus level. The dysbiosis of the skin microbiota in SD was specifically described as an alteration of bacteria populations commonly found on scalp skin, implying that managing and controlling the cutaneous bacterial microbiome can alleviate and prevent SD and pave the way for the development of new SD treatments.

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.

Sebaceous gland atrophy in seborrheic dermatitis of the scalp; a pilot study.

BACKGROUND: Sebaceous gland (SG) atrophy is well-documented in scalp lesions of psoriasis and has been considered as an important clue to psoriatic alopecia. However, its specificity for psoriasis has been questioned over the years. We hypothesize that SG atrophy is not specific for psoriasis and looked for its presence in biopsies of seborrheic dermatitis of the scalp. METHODS: We conducted a retrospective study of biopsy specimens of clinically suspected and histopathologically proven seborrheic dermatitis of the scalp for changes in SGs between January 1, 2014 and August 6, 2021. RESULTS: SGs lobules were smaller and narrower in five of the six cases of seborrheic dermatitis, and SG atrophy was present in four out of six cases. CONCLUSIONS: SG atrophy is observed in seborrheic dermatitis and is not specific for psoriasis or psoriatic alopecia.

Effectiveness of FastFung agar in the isolation of Malassezia furfur from skin samples.

BACKGROUND: Lipophilic basidiomycetous yeasts of the Malassezia genus can cause various skin diseases, such as seborrheic dermatitis, pityriasis versicolor, folliculitis and atopic dermatitis, and even life-threatening fungemia in newborns and immunocompromised individuals. Routine mycological media used in clinical practice do not contain sufficient lipid ingredients required for the growth of Malassezia species. A recently developed medium, FastFung agar, is promising for culturing fastidious fungal species. METHODS: In this study, we compared FastFung agar and mDixon agar for culturing Malassezia species from nasolabial fold and retroauricular specimens of 83 healthy individuals and 187 and 57 patients with acne vulgaris and seborrheic dermatitis, respectively. RESULTS: Malassezia species were identified using conventional tests and matrix-assisted laser desorption/ionisation mass spectrometry. In total, 96 of 654 samples (14.6%) contained Malassezia species. The total isolation rate was significantly higher in patients with seborrheic dermatitis (40.4%) than in healthy volunteers (21.7%; p < .05), and the rate of M. furfur isolation was significantly higher for patients with acne vulgaris (13.9%) and seborrheic dermatitis (24.6%) than for healthy individuals (1.5%; p < .05). FastFung agar was superior to mDixon agar in M. furfur isolation (p = .004) but showed similar performance in the case of non-M. furfur species (p > .05). Among cultured Malassezia species, perfect agreement between mDixon agar and FastFung agar was found only for M. globosa (κ = 0.90). CONCLUSION: Our results indicate that FastFung agar favours the growth of Malassezia species and should be useful in clinical mycology laboratories.