A comprehensive pathophysiology of dandruff and seborrheic dermatitis - towards a more precise definition of scalp health

Air pollution and skin diseases: A comprehensive evaluation of the associated mechanism

Air pollutants deteriorate the survival environment and endanger human health around the world. A large number of studies have confirmed that air pollution jeopardizes multiple organs, such as the cardiovascular, respiratory, and central nervous systems. Skin is the largest organ and the first barrier that protects us from the outside world. Air pollutants such as particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs) will affect the structure and function of the skin and bring about the development of inflammatory skin diseases (atopic dermatitis (AD), psoriasis), skin accessory diseases (acne, alopecia), auto-immune skin diseases (cutaneous lupus erythematosus(CLE) scleroderma), and even skin tumors (melanoma, basal cell carcinoma (BCC), squamous-cell carcinoma (SCC)). Oxidative stress, skin barrier damage, microbiome dysbiosis, and skin inflammation are the pathogenesis of air pollution stimulation. In this review, we summarize the current evidence on the effects of air pollution on skin diseases and possible mechanisms to provide strategies for future research.

The Evaluation of Dermatological Disease Profiles of Neurosurgery Inpatients: A Tertiary Clinic Experience

BACKGROUND

Both the skin and neuronal systems originate from the ectoderm. In patients hospitalized for neurosurgery, their skin may be affected by genetic and environmental factors.

OBJECTIVE

This study researched disease relationships by evaluating the profile of hospitalized neurosurgery patients who consulted with dermatology in a tertiary clinic (Neurosurgery Clinic, Ankara Training and Research Hospital, Ankara).

METHODS

This study included hospitalized neurosurgery patients who consulted with dermatology. Age, gender, type of hospitalization, neurosurgical diseases, and dermatology diseases were selected as study variables. The medical health records of the patients were retrospectively scanned and analyzed.

RESULTS

A total of 172 consultations were analyzed. The mean age of patients was 44.7 years old ranging from 1 year to 99 years old. The percentage of male patients was 54.7%; 25.5% of the patients were hospitalized for cerebral vascular diseases, 30.2% for spinal diseases, 22.1% for tumors, 12.2% for infections, and 1.2% for other neurosurgical diseases. The most commonly diagnosed dermatological disease in patients was drug eruptions (18.6%), followed by seborrheic dermatitis (16.2%) and contact dermatitis (14.5%).

CONCLUSION

According to this study, the most commonly diagnosed dermatological diseases in neurosurgery inpatients were drug eruption, contact dermatitis, and seborrheic dermatitis. The results of this study may be helpful in terms of neurosurgical training planning and treatment management.

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.

A newer approach in the treatment of seborrheic dermatitis with QR678® and QR678 Neo®-A prospective pilot study

BACKGROUND

Seborrheic dermatitis is a common chronic inflammatory skin disorder that affects the scalp and is characterized by erythema and oily scales. It could perhaps be difficult to control and could seriously degrade one's quality of life. The study's objective is to assess the effectiveness of intradermal administrations of QR678 Neo® hair growth factor therapy for the treatment of scalp seborrheic dermatitis in both men and women.

METHOD

Forty male and female patients with clinically diagnosed seborrheic dermatitis of the scalp in the age 18-45 years, not satisfactorily responding to standard therapy for at least 6 months, were included. 1 mL solution of QR678 Neo® was administered in the scalp skin of all patients at 3-week interval till eight sessions. Patients were advised to continue with antifungal shampoo and topical antifungal solution with steroid combination which they had been on during the treatment. Assessment of disease severity, dermoscopic evaluation, and self-assessment were done at baseline and at the end of the fourth and the eighth sessions.

RESULTS

Improvement was observed in adherent scalp flaking score after eighth session (mean = 12) compared to baseline (mean = 60). The dermoscopic evaluation showed a noticeable difference from baseline (mean = 11) in erythema and scaling with the Seborrheic Dermatitis Scalp Severity Index tool at the end of treatment (mean = 2). A high satisfaction score was given for the efficiency in the self-assessment questionnaire.

CONCLUSION

Our study proved that treatment with QR678 Neo® led to an improvement in the overall scalp condition by the resolution of flaking and inflammation.

A Comprehensive Review on HIV-Associated Dermatologic Manifestations: From Epidemiology to Clinical Management

Dermatological disorders are among the most prevalent manifestations of HIV infection/acquired immunodeficiency syndrome (AIDS). In this review, we aimed to characterize the various dermatologic presentations among HIV-infected patients with a detailed categorization of the mucocutaneous signs and symptoms, their etiopathogenic factors, and clinical management. In fact, cutaneous manifestations of HIV are quite various, ranging from AIDS-specific skin eruptions (xerosis, pruritic papular eruptions, eosinophilic folliculitis, and acne), opportunistic infections (herpes simplex, molluscum contagiosum, cutaneous leishmaniasis, bacillary angiomatosis, disseminated histoplasmosis, disseminated cryptococcosis, and zoster) to AIDS-related malignancies (Kaposi's sarcoma, lymphoma, and nonmelanoma skin cancers) and antiretroviral therapy (ART)-associated drug eruptions. We tried to classify HIV-related cutaneous presentations which can help clinicians for a better understanding of the various specific and nonspecific features of AIDS-associated cutaneous manifestations and management of the condition.

Malassezia restricta-mediated Lipoperoxidation: A Novel Trigger in Dandruff

Dandruff is a common scalp disorder with multiple microbial and host-related factors contributing to its aetiology, including alterations in scalp sebum. Despite existing evidence that the yeast Malassezia restricta plays a key role in the onset of dandruff, the interplay of these factors is poorly understood. Recently, squalene monohydroperoxide and malondialdehyde were established as biomarkers of dandruff-afflicted scalp, highlighting the role of sebum lipoperoxidation in the triggering and maintenance of dandruff, although its mechanism of action is unknown. The current study provides evidence that M. restricta mediates sebum peroxidation, leading to production of squalene monohydroperoxide and malondialdehyde. Furthermore, in vitro data show that these lipoperoxidation products act on epidermal cells and alter the skin barrier. These results support the role of Malassezia restricta-induced lipoperoxides as triggers of dandruff, which suggests that blocking their production could be a novel anti-dandruff treatment approach.

Saccharide isomerate ameliorates cosmetic scalp conditions in a Chinese study population

BACKGROUND

Scalp conditions such as flaky or oily scalp affect people across ethnicities and age groups. In addition to flaking, increased sebum secretion, itching, and compromised scalp barrier function were described. Scalp conditions are aesthetically disturbing and may cause psychological distress in affected individuals who are looking for mild and effective treatment at the same time. Saccharide isomerate has a long history as a skin moisturizer, and it was found to improve skin barrier function, also suggesting possible beneficial effects on scalp.

AIMS

To provide relevant claim substantiation to introduce saccharide isomerate as a new scalp care active against scalp flaking condition.

MATERIAL AND METHODS

We conducted a placebo-controlled clinical study in an adult Chinese population affected by dandruff scalp as assessed by an adherent scalp flaking score. We monitored transepidermal water loss (TEWL), sebum secretion, and scalp flaking during 28 days.

RESULTS

Formulations containing Saccharide isomerate significantly improved all parameters both over time as well as compared to the placebo formulation.

CONCLUSION

We propose Saccharide isomerate for cosmetic formulations directed toward improving scalp conditions such as dandruff or oily scalp.

The Use of Urea Cream for Hand Eczema and Urea Foam for Seborrheic Dermatitis and Psoriasiform Dermatoses of the Scalp

PURPOSE

Urea as an ingredient in topical skin applications can aid skin integrity and hydration and have keratolytic, anti-fungal, anti-bacterial, and anti-pruritic effects. Skin conditions that urea-containing formulations have been utilized to treat include hand eczema/dermatitis, seborrheic dermatitis and psoriasiform dermatoses of the scalp. Two monocentric, simple blind, observational studies were carried out in healthy participants to examine the efficacy and safety of two urea-containing products in these skin conditions.

PATIENTS AND METHODS

Study 1 tested the actions of a commercially available 30% urea topical cream on hand eczema. The product was applied ≥2/day for 28 ±2 days. Transepidermal water loss, skin redness, skin hydration, and participant ratings of efficacy and qualities were assessed prior to first product application and on days 14 and 29. Study 2 tested the actions of a commercially available foaming product containing 10% urea on seborrheic dermatitis and scalp psoriasiform dermatoses. The product was applied ≥2/day for 28 ±2 days. Desquamation index and surface occupied by squames, analysis of extracted squames, microscopic assessment of scalp photos and participant ratings of product efficacy and qualities was carried out prior to first product application and on days 14 and 29.

RESULTS

In Study 1 (n = 20 females), results showed a significant (p < 0.05) decrease in transepidermal water loss, with an increase in hydration level of the upper skin layers, and a decrease in skin redness. In Study 2 (n = 13 females, 7 males), product use led to significant (p < 0.05) decreases in desquamation measures and dryness. In both studies, the majority of participants "agreed" or "slightly agreed" that the product had good efficacy and was easy to apply. No adverse reactions were reported.

CONCLUSION

These findings point to the utility of urea in topically applied vehicles for hand eczema, seborrheic dermatitis, and psoriasiform dermatoses.

Herbal Therapy for the Treatment of Seborrhea Dermatitis

Seborrhea dermatitis is a skin disorder that usually appears on parts of the body that have high density of sebaceous glands, such as the face, chest, and scalp. Clinical manifestations that generally appear as scaly skin and erythema. Seborrhea dermatitis is also known as one of the causes of alopecia. Treatments that can be used for seborrhea dermatitis are antifungal, anti-inflammatory, keratolytic, and coal tar. There are concerns about poor adherence, resistance, and some side effects of drugs that have been used in the treatment of seborrhea dermatitis. Concerns regarding these issues increase the urgency for the development of new therapeutic agents in the treatment of seborrhea dermatitis. Research on medicinal plants has enormous potential to produce compounds with new structures and bioactivity. This review discusses clinical and in vitro studies related to the activity of several medicinal plants that have potential as a treatment for seborrhea dermatitis, as well as the compounds that play a role in these activities. Literature searches were carried out on the PubMed, Taylor & Francis, and SpringerLink databases using Boolean Operators to get 25 articles that match the keywords used. Of the 25 articles, six were clinical trials, while 19 were in vitro studies of Malassezia. Several plants have potential as promising therapeutic agents for the treatment of seborrhea dermatitis by inhibiting the growth of Malassezia, decreasing sebum secretion, and decreasing symptoms associated with seborrhea dermatitis such as itching, pain or burning sensation, and redness.

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.

The Efficacy and Safety of Pimecrolimus in Patients With Facial Seborrheic Dermatitis: A Systematic Review of Randomized Controlled Trials

Facial seborrheic dermatitis (SD) is a chronic inflammatory skin condition that can affect the quality of life with frequent recurrences. There is no medication as yet to cure this disease completely. There are four general categories of agents that are used to treat SD: antifungal agents, keratolytics, corticosteroids, and lastly calcineurin inhibitors. Topical therapies are the mainstream line of treatment to be used for this skin condition.

The objective of this article is to critically review the published data in the literature on the use of topical pimecrolimus 1% topical cream as an option for treating facial SD. The final purpose of this review is to answer two questions: whether pimecrolimus topical cream is effective for the treatment of SD compared to the conventional current treatments and how safe is this treatment. 

The PubMed, Clinicaltrials.gov, MEDLINE + Embase, and Cochrane library databases were searched for original randomized clinical trials (RCTs) evaluating pimecrolimus 1% topical cream and comparing it with other topical treatments for SD. A systematic review and meta-analysis were then conducted on the selected studies by grading the evidence and qualitative comparison of results among and within studies. A total of five studies were included in the review; however, only four were eligible for inclusion in the meta-analysis, in which pimecrolimus was compared with other treatments for the management of facial SD.

Pimecrolimus was found to be an effective topical treatment for facial SD, as it showed considerable desirable control of the symptoms in patients with facial SD clinically, in addition to a lower recurrence or relapsing rates; however, it had more side effects compared to other topical treatments, but the side effects were mild and tolerable.

Malassezia: Zoonotic Implications, Parallels and Differences in Colonization and Disease in Humans and Animals

Malassezia spp. are commensals of the skin, oral/sinonasal cavity, lower respiratory and gastrointestinal tract. Eighteen species have been recovered from humans, other mammals and birds. They can also be isolated from diverse environments, suggesting an evolutionary trajectory of adaption from an ecological niche in plants and soil to the mucocutaneous ecosystem of warm-blooded vertebrates. In humans, dogs and cats, Malassezia-associated dermatological conditions share some commonalities. Otomycosis is common in companion animals but is rare in humans. Systemic infections, which are increasingly reported in humans, have yet to be recognized in animals. Malassezia species have also been identified as pathogenetic contributors to some chronic human diseases. While Malassezia species are host-adapted, some species are zoophilic and can cause fungemia, with outbreaks in neonatal intensive care wards associated with temporary colonization of healthcare worker’s hands from contact with their pets. Although standardization is lacking, susceptibility testing is usually performed using a modified broth microdilution method. Antifungal susceptibility can vary depending on Malassezia species, body location, infection type, disease duration, presence of co-morbidities and immunosuppression. Antifungal resistance mechanisms include biofilm formation, mutations or overexpression of ERG11, overexpression of efflux pumps and gene rearrangements or overexpression in chromosome 4.

Is cutaneous microbiota a player in disease pathogenesis? Comparison of cutaneous microbiota in psoriasis and seborrheic dermatitis with scalp involvement

BACKGROUND

Knowledge about cutaneous microbiota in psoriasis vulgaris and seborrheic dermatitis is limited, and a comparison of microbiota in the two diseases was not yet previously undertaken.

AIMS/OBJECTIVES

This study aimed to compare the scalp lesional and non-lesional microbiota in psoriasis vulgaris and seborrheic dermatitis with that in a healthy control group.

METHODS

Fifty samples were taken with sterile swabs from patients' and controls' scalps, and 16S rRNA gene sequencing analyses were performed.

RESULTS

Alpha and beta diversity analyses showed that bacterial load and diversity were significantly increased in psoriasis vulgaris and seborrheic dermatitis lesions compared to the controls. As phyla, Actinobacteria decreased and Firmicutes increased, while as genera, Propionibacterium decreased; Staphylococcus, Streptococcus, Aquabacterium, Neisseria and Azospirillum increased in lesions of both diseases. Specifically, Mycobacterium, Finegoldia, Haemophilus and Ezakiella increased in psoriasis vulgaris and Enhydrobacter, Micromonospora and Leptotrichia increased in seborrheic dermatitis lesions. Mycobacterium, Ezakiella and Peptoniphilus density were higher in psoriasis vulgaris compared to seborrheic dermatitis lesions. The bacterial diversity and load values of non-lesional scalp in psoriasis vulgaris and seborrheic dermatitis lay between those of lesional areas and controls.

LIMITATIONS

The small sample size is the main limitation of this study.

CONCLUSION

Higher bacterial diversity was detected in lesions of both psoriasis and seborrheic dermatitis compared to the controls, but similar alterations were observed when the two diseases were compared. Although these differences could be a result rather than a cause of the two diseases, there is a need to analyze all members of the microbiota and microbiota-host interactions.

The Human Skin Microbiome in Selected Cutaneous Diseases

The human skin harbors a wide variety of microbes that, together with their genetic information and host interactions, form the human skin microbiome. The role of the human microbiome in the development of various diseases has lately gained interest. According to several studies, changes in the cutaneous microbiota are involved in the pathophysiology of several dermatoses. A better delineation of the human microbiome and its interactions with the innate and adaptive immune systems could lead to a better understanding of these diseases, as well as the opportunity to achieve new therapeutic modalities. The present review centers on the most recent knowledge on skin microbiome and its participation in the pathogenesis of several skin disorders: atopic and seborrheic dermatitis, alopecia areata, psoriasis and acne.

Evaluation of a new-formula shampoo containing 6% glycyrrhetinic acid complex for scalp seborrheic dermatitis: A pilot study

Background

Scalp seborrheic dermatitis (SD) is a chronic inflammatory dermatosis associated with sebum imbalance and proliferation of Malassezia species. Various antifungal shampoos are commonly used for scalp SD.

Aims

Glycyrrhetinic acid is known to have antioxidative, anti‐inflammatory, and anti‐allergic effects. This study was designed to evaluate the effectiveness of a new‐formula shampoo that contains glycyrrhetinic acid for the treatment of scalp SD.

Patients/Methods

Thirty‐four patients were enrolled and treated with the 6% glycyrrhetinic acid complex shampoo. Efficacy was assessed clinically with Dermatology Life Quality Index (DLQI) and Adherent Scalp Flaking Score (ASFS) by the same dermatologist at baseline, week 2, and week 5. Among the 24 subjects with the most significant clinical improvement, four common microorganisms from scalp samples were analyzed by quantitative polymerase chain reaction (qPCR) at baseline, and week 5.

Results

The DLQI and ASFS at week 2 and week 5 improved significantly relative to baseline. The bacteria profiles showed a significant increase of Cutibacterium acnes and a decrease of Staphylococcus epidermidis at week 5. The fungi profiles showed significant decreases of both Malassezia restricta and Malassezia globosa. The ratio of C. acne to S. epidermidis increased significantly from 0.93 at baseline to 1.55 at week 5. The ratio of M. restricta to M. globosa decreased from 5.02 at baseline to 1.00 at week 5.

Conclusions

The effectiveness of this new regimen was objectively demonstrated at the clinical and microbiological levels. This new formula may alleviate the bacterial and fungal dysbiosis in scalp SD.

Targeted Delivery of Zinc Pyrithione to Skin Epithelia

Zinc pyrithione (ZnPT) is an anti-fungal drug delivered as a microparticle to skin epithelia. It is one of the most widely used ingredients worldwide in medicated shampoo for treating dandruff and seborrheic dermatitis (SD), a disorder with symptoms that include skin flaking, erythema and pruritus. SD is a multi-factorial disease driven by microbiol dysbiosis, primarily involving Malassezia yeast. Anti-fungal activity of ZnPT depends on the cutaneous availability of bioactive monomeric molecular species, occurring upon particle dissolution. The success of ZnPT as a topical therapeutic is underscored by the way it balances treatment efficacy with formulation safety. This review demonstrates how ZnPT achieves this balance, by integrating the current understanding of SD pathogenesis with an up-to-date analysis of ZnPT pharmacology, therapeutics and toxicology. ZnPT has anti-fungal activity with an average in vitro minimum inhibitory concentration of 10-15 ppm against the most abundant scalp skin Malassezia species (Malassezia globosa and Malassezia restrica). Efficacy is dependent on the targeted delivery of ZnPT to the skin sites where these yeasts reside, including the scalp surface and hair follicle infundibulum. Imaging and quantitative analysis tools have been fundamental for critically evaluating the therapeutic performance and safety of topical ZnPT formulations. Toxicologic investigations have focused on understanding the risk of local and systemic adverse effects following exposure from percutaneous penetration. Future research is expected to yield further advances in ZnPT formulations for SD and also include re-purposing towards a range of other dermatologic applications, which is likely to have significant clinical impact.

Effective Picosecond Nd:YAG laser on seborrheic dermatitis and its mechanism

BACKGROUND

The Picosecond Nd:YAG laser has advantages in skin rejuvenation, which has little damage to surrounding tissues due to the ultra-short pulse width. We perform clinical application of Picosecond Nd:YAG laser's tender skin mode, which could improve the seborrheic dermatitis.

MATERIALS AND METHODS

Sixty-three subjects with facial seborrheic dermatitis are randomized to be control and observation groups. Records regarding skin subjective improvement, skin barrier function-related data, skin microbial status, and dermoscopy detection of the two patient groups before and after treatments are investigated.

RESULTS

Improvements of erythema and scales in observation group are significant compared with controls (p < 0.05). In terms of skin barrier function, there are significant changes regarding transepidermal water loss and epidermal seborrhea content in observation group after the laser treatments. Skin microbial state, pityrosporum furfur, and Demodex significantly decrement in observation group. Microscopical findings of infiltration mode advise that scales and capillary congestion and dilatation are significantly improved in observation group. Compared with controls, epidermal gloss increases, pore fineness improves, and capillary density decreases in the observation group.

CONCLUSIONS

Picosecond Nd:YAG laser could efficiently decrease erythema area and seborrheic dermatitis scales and reduce pruritus incidence. The sebaceous gland secretion of seborrhea and multiplying of epidermal parasitic microbiological are inhibited after laser treatment. Less epidermal seborrhea content and inflammation are induced by parasitic microbiology, which is helpful for skin barrier function and microvascular remodeling.

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.

Essential oils as Potential Source of Anti-dandruff Agents: A Review

BACKGROUND

Dandruff is a frequently occurring scalp problem that causes significant discomfort to approximately 50% population at some stage of life, especially post-puberty and pre-adult age.

OBJECTIVE

This review aims to summarize the recent findings regarding the anti-fungal properties of herbal essential oils against pathogens involved in dandruff prognosis.

METHODS

A literature search of studies published between 2000 and 2020 was conducted over databases: PubMed, Google Scholar, Scopus, and Science direct. Literature was explored using the guidelines given in Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

RESULTS

Dandruff, characterized by clinical symptoms of dryness, pruritis, scaly, and flaky scalp, is considered a pri-mary manifestation of seborrheic dermatitis. Amongst various etiological and pathophysiological factors, a significant role of yeasts, primarily species of Malassezia, Candida, has been strongly correlated with dandruff. At the same time, incidences of M. furfur, M. restricta, and M. globosa are high compared to others. Due to relapse of symptoms with the withdrawal of conventional anti-dandruff products. Essential oils of herbal origin, such as tea tree oil, lime oil, rose-mary oil, have gained global importance in dermatology. These oils are rich in secondary aromatic metabolites, espe-cially terpenes and phenolic components that impart substantial antimicrobial properties and resisting biofilm production.

CONCLUSION

Based on the available information, we can conclude that essential oils have tremendous potential to be developed as anti-dandruff products; however, further studies are warranted to establish their efficacy in dandruff cures.

Skin Commensal Fungus Malassezia and Its Lipases

Malassezia is the most abundant genus in the fungal microflora found on human skin, and it is associated with various skin diseases. Among the 18 different species of Malassezia that have been identified to date, M. restricta and M. globosa are the most predominant fungal species found on human skin. Several studies have suggested a possible link between Malassezia and skin disorders. However, our knowledge on the physiology and pathogenesis of Malassezia in human body is still limited. Malassezia is unable to synthesize fatty acids; hence, it uptakes external fatty acids as a nutrient source for survival, a characteristic compensated by the secretion of lipases and degradation of sebum to produce and uptake external fatty acids. Although it has been reported that the activity of secreted lipases may contribute to pathogenesis of Malassezia, majority of the data were indirect evidences; therefore, enzymes' role in the pathogenesis of Malassezia infections is still largely unknown. This review focuses on the recent advances on Malassezia in the context of an emerging interest for lipases and summarizes the existing knowledge on Malassezia, diseases associated with the fungus, and the role of the reported lipases in its physiology and pathogenesis.

Eczema and the older person

Age-related changes lead to an increase in skin problems, and around 70% of older people have a treatable skin condition. However, ageing and poor physical health can make it difficult for older people to care for their skin. Eczema, a chronic inflammatory skin condition, where the skin becomes red, inflamed, itchy and scaly, can develop easily in older adults. This can, in turn, become infected and cause discomfort and health problems. This article explains how ageing affects the skin, how eczema can develop and how it can be treated, also touching upon the different types of eczema. It aims to equip community nurses with knowledge about this common condition and how to recognise and manage it.

Skin microbiota in health and disease: From sequencing to biology

Microbiota live in a closely regulated interaction with their environment, and vice versa. The presence and absence of microbial entities is greatly influenced by features of the niche in which they thrive. Characteristic of this phenomenon is that different human skin sites harbor niche‐specific communities of microbes. Microbial diversity is considerable, and the current challenge lies in determining which microbes and (corresponding) functionality are of importance to a given ecological niche. Furthermore, as there is increasing evidence of microbial involvement in health and disease, the need arises to fundamentally understand microbiome processes for application in health care, nutrition and personal care products (e.g. diet, cosmetics, probiotics). This review provides a current overview of state‐of‐the‐art sequencing‐based techniques and corresponding data analysis methodology for profiling of complex microbial communities. Furthermore, we also summarize the existing knowledge regarding cutaneous microbiota and their human host for a wide range of skin diseases.

Biophysical characteristics of dandruff-affected scalp categorized on the basis of sebum levels

BACKGROUND

Various sebum levels can be detected in dandruff-affected scalps. However, few studies have compared the biophysical characteristics of dandruff scalps categorized based on sebum levels.

AIMS

To investigate and compare the biophysical characteristics of dandruff-affected scalps categorized based on sebum levels.

METHODS

Fifty-four Korean women with dandruff and 30 healthy Korean women underwent physiological measurements, including evaluation of sebum and hydration levels, pH, and transepidermal water loss (TEWL) in the scalp. The levels of the biomarkers of interleukin-8 (IL-8) and kallikrein 5 (KLK5) and corneodesmosomes were investigated in the stratum corneum (SC) of the scalp.

RESULTS

Dandruff was categorized as dry (low-sebum, n = 25) or oily (high-sebum, n = 29) based on a sebum cutoff level of 97.82 μg/cm² . Both dry and oily dandruff-affected scalps showed significantly decreased hydration levels and increased pH and TEWL compared with healthy subjects, with hydration levels being lower in dry dandruff-affected scalps. IL-8 expression was significantly increased in the oily dandruff-affected scalp. In addition, both dry and oily dandruff-affected scalps showed significantly increased KLK5 levels in the SC, with the levels being higher in oily dandruff-affected scalps. Altered distribution of corneodesmosomes, present on the entire surface area of the corneocytes, was notable in oily dandruff-affected scalps.

CONCLUSION

The biophysical characteristics of the two types of dandruff represent the influence of different characteristics, including hydration levels, expression of IL-8 and KLK5, and corneodesmosome distribution. Thus, strategies to reduce dandruff levels should differ according to sebum levels.

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

The underlying mechanism of seborrheic dermatitis (SD) is poorly understood but major scientific progress has been made in recent years related to microbiology, immunology and genetics. In light of this, the major goal of this article was to summarize the most recent articles on SD, specifically related to underlying pathophysiology. SD results from Malassezia hydrolysation of free fatty acids with activation of the immune system by the way of pattern recognition receptors, inflammasome, IL-1β and NF-kB. M. restricta and M. globosa are likely the most virulent subspecies, producing large quantities of irritating oleic acids, leading to IL-8 and IL-17 activation. IL-17 and IL-4 might play a big role in pathogenesis, but this needs to be further studied using novel biologics. No clear genetic predisposition has been established; however, recent studies implicated certain increased-risk human leucocyte antigen (HLA) alleles, such as A*32, DQB1*05 and DRB1*01 as well as possible associations with psoriasis and atopic dermatitis (AD) through the LCE3 gene cluster while SD, and SD-like syndromes, shares genetic mutations that appear to impair the ability of the immune system to restrict Malassezia growth, partially due to complement system dysfunction. A paucity of studies exists looking at the relationship between SD and systemic disease. In HIV, SD is thought to be secondary to a combination of immune dysregulation and disruption in skin microbiota with unhindered Malassezia proliferation. In Parkinson's disease, SD is most likely secondary to parasympathetic hyperactivity with increased sebum production as well as facial immobility which leads to sebum accumulation.

Malassezia and Staphylococcus dominate scalp microbiome for seborrheic dermatitis

Seborrheic dermatitis (SD) is a common disease of the human scalp that causes physical damage and psychological problems for patients. Studies have indicated that dysbiosis of the scalp microbiome results in SD. However, the specific fungal and bacterial microbiome changes related to SD remain elusive. To further investigate the fungal and bacterial microbiome changes associated with SD, we recruited 57 SD patients and 53 healthy individuals and explored their scalp microbiomes using next generation sequencing and the QIIME and LEfSe bioinformatics tools. Skin pH, sebum secretion, hydration, and trans-epidermal water loss (TWEL) were also measured at the scalp. We found no statistically significant differences between the normal and lesion sites in SD patients with different subtypes of dandruff and erythema. However, the fungal and bacterial microbiome could differentiate SD patients from healthy controls. The presence of Malassezia and Aspergillus was both found to be potential fungal biomarkers for SD, while Staphylococcus and Pseudomonas were found to be potential bacterial biomarkers. The fungal and bacterial microbiome were divided into three clusters through co-abundance analysis and their correlations with host factors indicated the interactions and potential cooperation and resistance between microbe communities and host. Our research showed the skin microbe dysbiosis of SD and highlighted specific microorganisms that may serve as potential biomarkers of SD. The etiology of SD is multi-pathogenetic-dependent on the linkage of several microbes with host. Scalp microbiome homeostasis could be a promising new target in the risk assessment, prevention, and treatment of SD disease.

Exploring Anti-Fungal, Anti-Microbial and Anti-Inflammatory Properties of a Topical Non-Steroidal Barrier Cream in Face and Chest Seborrheic Dermatitis

INTRODUCTION

The pathogenesis of seborrheic dermatitis (SD) is multifactorial and traditional treatments may not target all aspects of it. The aim of this study was to evaluate short-term anti-fungal, anti-microbial, anti-inflammatory and anti-pruritus properties of a novel non-steroidal cream (NSC) containing piroctone olamine, zinc salt of L-pyrrolidone carboxylate (PCA), hydroxyphenyl propamidobenzoic acid, biosaccharide gum-2 and stearyl glycyrrhetinate in patients with face and chest SD.

METHODS

Twelve male subjects affected by SD, presenting face and chest manifestations, were enrolled. Patients were instructed to apply NSC twice a day, performing regular visits at baseline (W0), after 7 (W1) and 14 (W2) days of treatment. A limitation of the study was that no control group treated with the vehicle without active ingredients was enrolled. To evaluate the efficacy of the NSC, investigator's assessments were represented by scoring index (SI) and investigator's global assessment score (IGA). In order to assess NSC anti-fungal and anti-microbial effects, skin scale scrapings were collected and used for Malassezia furfur (MF) and Staphylococcus epidermidis (SE) cultures. In parallel, in order to assess NSC anti-inflammatory effects, gene expression of IL-1α, IL-1β, IL-6, IL-8, and TNF-α was assessed. In addition, anti-pruritus effects were also evaluated through gene expression of cathepsin S and L-histidine decarboxylase.

RESULTS

SI mean scores significantly decreased at W1 and, to a greater extent, at W2 compared with W0. The IGA score registered an important improvement efficacy both for face and chest, from W1 to W2. MF and SE growth was already inhibited at W1, with a more pronounced decrease at W2. Gene expression of all analyzed mediators was significantly reduced at W1 compared to W0.

CONCLUSION

In conclusion, our assessment is that NSC is an effective and well tolerated treatment option for SD with anti-fungal, anti-microbial and anti-inflammatory properties.

TRIAL REGISTRATION

ISRCTN registry, ISRCTN77871064 (retrospectively registered October 17, 2019). EudraCT number, 2019-003813-32.

FUNDING

ISDIN.

Clinical study on treatment of facial seborrheic dermatitis with intense pulsed light combined with 30% supramolecular salicylic acid

OBJECTIVES

In this study, we investigated the effects of intense pulsed light (IPL) combined with 30% supramolecular salicylic acid on facial seborrheic dermatitis.

METHODS

A total of 45 patients with mild or moderate facial seborrheic dermatitis were selected from our hospital between September 2018 and September 2019. The patients were divided into three groups consisting of 15 patients each. The first group was exposed to a combination of IPL and 30% supramolecular salicylic acid treatment, the second group was exposed to the IPL treatment alone, and the third group was exposed to the 30% supramolecular salicylic acid treatment alone. They were treated once every 4 weeks in three consecutive rounds.

RESULTS

Facial lesions and symptoms were observed 4 and 12 weeks after the first treatment, and adverse reactions were recorded. The combination group showed significant improvement in symptoms 4 weeks after the first treatment, while the individual treatment groups showed no significant improvement. After three rounds of treatments, seborrheic dermatitis had significantly decreased in the three groups; the efficacy of the combined treatment group was significantly higher than that of the IPL group and the 30% supramolecular salicylic acid group.

CONCLUSION

IPL combined with 30% supramolecular salicylic acid was effective in the treatment of facial seborrheic dermatitis and provided a quicker result with no adverse reactions.

Dynamic Thiol/Disulfide Balance in Patients with Seborrheic Dermatitis: A Case-Control Study

Background:

Seborrheic dermatitis is a chronic, inflammatory skin disease, in which many endogenous and exogenous factors play a role. Recent studies have shown that oxidative stress increases in these patients. The role of the dynamic thiol/disulfide homeostasis, an important component of the oxidative stress, in the pathogenesis of seborrheic dermatitis has not yet been investigated.

Objectives:

The objective was to investigate the relationship between the dynamic thiol/disulfide balance in the plasma of seborrheic dermatitis patients and disease severity.

Methods:

In this case–control study, 70 seborrheic dermatitis patients and 61 age- and sex-matched healthy controls were included. Thiol/disulfide homeostasis was calculated from venous blood samples, and tests were performed by automated spectrophotometric method. The thiol/disulfide balance between the patient and control groups was compared. In addition, disease severity and other demographic characteristics and thiol/disulfide balance parameters were compared.

Results:

Native and total thiols were significantly higher in the patient group than that in the control group (P < 0.001). Disulfide levels were nonsignificantly lower in the patient group than controls (P = 0.821). Patients' age and age at the onset of disease were found to have a negative correlation with native and total thiol levels.

Conclusion:

Higher levels of thiols in the serum may be responsible for the increased proliferation of seborrheic dermatitis lesions. To the best of the authors' knowledge, this is the first report on the correlation between thiol/disulfide homeostasis in patients with seborrheic dermatitis.

The diversity and abundance of fungi and bacteria on the healthy and dandruff affected human scalp

Dandruff is a skin condition that affects the scalp of up to half the world's population, it is characterised by an itchy, flaky scalp and is associated with colonisation of the skin by Malassezia spp. Management of this condition is typically via antifungal therapies, however the precise role of microbes in the aggravation of the condition are incompletely characterised. Here, a combination of 454 sequencing and qPCR techniques were used to compare the scalp microbiota of dandruff and non-dandruff affected Chinese subjects. Based on 454 sequencing of the scalp microbiome, the two most abundant bacterial genera found on the scalp surface were Cutibacterium (formerly Propionibacterium) and Staphylococcus, while Malassezia was the main fungal inhabitant. Quantitative PCR (qPCR) analysis of four scalp taxa (M. restricta, M. globosa, C. acnes and Staphylococcus spp.) believed to represent the bulk of the overall population was additionally carried out. Metataxonomic and qPCR analyses were performed on healthy and lesional buffer scrub samples to facilitate assessment of whether the scalp condition is associated with differential microbial communities on the sampled skin. Dandruff was associated with greater frequencies of M. restricta and Staphylococcus spp. compared with the healthy population (p<0.05). Analysis also revealed the presence of an unclassified fungal taxon that could represent a novel Malassezia species.

Seborrheic Dermatitis: Three Novel Trichoscopic Signs and Its Correlation to Malassezia sp. Colonization

Seborrheic dermatitis (SD) is a chronic recurrent erythemato-squamous condition that affects seborrheic areas causing flaking, erythema, and pruritus. Etiology is multifactorial and the role of Malassezia sp.remains controversial. We present a series of 12 patients with trichoscopic and direct microscopic exams. We analyzed the presence of the already known SD trichoscopic signs and its correlation to the amount of Malassezia sp. in the scalp. We describe three novel signs: the "dandelion" vascular conglomerate, the "cherry blossom" vascular pattern, and the intrafollicular oily material; of which the "dandelion" vascular conglomerate was the only trichoscopic sign to correlate with Malassezia colonization. This study correlates trichoscopic signs in SD and the quantity of Malassezia sp. We describe three new signs that can be useful to determine indirectly the fungal colonization of the scalp in SD.

Fenugreek Leaf Extract and Its Gel Formulation Show Activity Against Malassezia furfur

Malassezia spp. are commensal yeasts that can cause cutaneous ailments such as dandruff and seborrheic dermatitis. We sought to develop a cost-effective, herbal formulation for the treatment of cutaneous ailments related to Malassezia spp. Aqueous and ethanolic extracts of fenugreek (Trigonellafoenum-graecum L.) leaves exhibited activity against a clinical isolate and commercial strain of Malassezia furfur. The extracts were also found to be active against other pathogenic fungi such as Aspergillus niger and Candida albicans. Qualitative and quantitative phytochemical evaluation of aqueous extract showed a predominant presence of flavonoids apart from alkaloids, saponins, carbohydrates, phenols, and proteins. Gel formulation of 30% aqueous fenugreek leaf extract was developed and optimized using sodium alginate as a gelling agent. The formulation showed good physicochemical characteristics and retained activity against M. furfur during 3-month accelerated stability studies. Furthermore, the developed herbal gel formulation did not show any irritation or sensitization in New Zealand rabbits after topical application, proving its cutaneous safety. Thus, topical gel formulation containing fenugreek leaf aqueous extract could be a safe and effective herbal treatment for various cutaneous fungal infections, including dandruff.

Dermatologic Problems Commonly Seen by the Allergist/Immunologist

Allergists/immunologists see a variety of skin disorders, some of which have a known immunologic basis whereas others do not. We review the prevalence, etiology, clinical presentation, and effective and low-cost care of common dermatologic conditions seen in outpatient practices. Conditions discussed include pityriasis alba, seborrheic dermatitis, rosacea, acne, tinea infections, intertrigo, lichen planus, tinea versicolor, lichen simplex chronicus, scabies, pityriasis rosea, keratosis pilaris, and seborrheic keratosis. An understanding of frequently encountered cutaneous diseases and their therapies will help provide immediate access to treatment and improve the experience for both the affected patient and the clinician.

The role of the microbiome in scalp hair follicle biology and disease

The skin surface microbiome and its role in skin diseases have received increasing attention over the past years. Beyond, there is evidence for a continuous exchange with the cutaneous immune system in healthy skin, where hair follicles (HFs) provide unique anatomical niches. Especially, scalp HFs form large tubular invaginations, which extend deeply into the skin and harbour a variety of microorganisms. The distinct immunology of HFs with enhanced immune cell trafficking in superficial compartments in juxtaposition to immune-privileged sites crucial for hair follicle cycling and regeneration makes this organ a highly susceptible structure. Depending on composition and penetration depth, microbiota may cause typical infections, but may also contribute to pro-inflammatory environment in chronic inflammatory scalp diseases. Involvement in hair cycle regulation and immune cell maturation has been postulated. Herein, we review recent insights in hair follicle microbiome, immunology and penetration research and discuss clinical implications for scalp health and disease.

Treatment of seborrheic dermatitis: a comprehensive review

Seborrheic dermatitis (SD) is a chronic, recurring inflammatory skin disorder that manifests as erythematous macules or plaques with varying levels of scaling associated with pruritus. The condition typically occurs as an inflammatory response to Malassezia species and tends to occur on seborrheic areas, such as the scalp, face, chest, back, axilla, and groin areas. SD treatment focuses on clearing signs of the disease; ameliorating associated symptoms, such as pruritus; and maintaining remission with long-term therapy. Since the primary underlying pathogenic mechanisms comprise Malassezia proliferation and inflammation, the most commonly used treatment is topical antifungal and anti-inflammatory agents. Other broadly used therapies include lithium gluconate/succinate, coal tar, salicylic acid, selenium sulfide, sodium sulfacetamide, glycerin, benzoyl peroxide, aloe vera, mud treatment, phototherapy, among others. Alternative therapies have also been reported, such as tea tree oil, Quassia amara, and Solanum chrysotrichum. Systemic therapy is reserved only for widespread lesions or in cases that are refractory to topical treatment. Thus, in this comprehensive review, we summarize the current knowledge on SD treatment and attempt to provide appropriate directions for future cases that dermatologists may face.

Prevalence and determinants of seborrhoeic dermatitis in a middle-aged and elderly population: the Rotterdam Study

BACKGROUND

Seborrhoeic dermatitis is a chronic relapsing inflammatory skin disease with unclear pathophysiological mechanisms.

OBJECTIVES

To establish which lifestyle and physiological determinants are associated with seborrhoeic dermatitis.

METHODS

Seborrhoeic dermatitis was diagnosed by a trained physician during a full-body skin examination within the Rotterdam Study, a prospective population-based cohort study in middle-aged and elderly people. The current design is a comparative cross-sectional study embedded in the Rotterdam Study. Potential factors were identified from the literature and analysed in a multivariable logistic regression, including: age, sex, obesity, skin colour, stress, depression, education level, hypertension, climate, xerosis cutis, alcohol and tobacco use.

RESULTS

Of the 5498 participants, 788 participants were diagnosed with seborrhoeic dermatitis (14·3%). We found associations between seborrhoeic dermatitis and male sex [adjusted odds ratio (OR) 2·09, 95% confidence interval (CI) 1·77-2·47], darker skin (adjusted OR 0·39, 95% CI 0·22-0·69), season (summer vs. winter: adjusted OR 0·63, 95% CI 0·48-0·82) and generalized xerosis cutis (adjusted OR 1·41, 95% CI 1·11-1·80).

CONCLUSIONS

Seborrhoeic dermatitis is one of the most common inflammatory dermatoses in middle-aged and elderly individuals, especially during winter. Men, and people with a light and dry skin were most likely to have seborrhoeic dermatitis.

Reinforcement of barrier function and scalp homeostasis by Senkyunolide A to fight against dandruff

OBJECTIVE

Senkyunolide-A (SENKY) can be isolated from Apium graveolens seed oil obtained using supercritical CO₂ extraction. SENKY and its parent compounds, the N-butyl phthalides, have been demonstrated to protect cells from CO poisoning, to prevent diabetes mellitus and to decrease cancer cell proliferation. This study was undertaken to evaluate in vitro and in vivo the effect of SENKY on epidermal function improvement, Malassezia effect control, scalp soothing and dandruff reduction via skin protection-related pathways.

METHODS

DNA-array and proteomic studies were performed on human keratinocytes, sebocytes and skin explants to demonstrate SENKY activities. Two clinical evaluations were performed under dermatologist control on 106 volunteers, with greasy or dry scalp, experiencing dandruff, itching and redness. Volunteers tested a shampoo followed, or not, by a leave-on, containing SENKY, or their placebos. Dandruff severity and redness were scored on the scalp. Moisturization and sebum release were recorded using relevant measuring apparatus. Itching and scratching evaluations came from volunteers' self-declarations.

RESULTS

DNA-array studies on keratinocytes showed a clear regulation of skin barrier functions and epidermis defence pathways. Upregulation of epidermal differentiation complex genes was observed. These preliminary observations were reinforced by immunocytochemistry and immunohistochemistry studies showing a significant increase of involucrin, filaggrin, loricrin, SPRR, LC3B and ceramide 2 productions. Tight-junctions and corneodesmosomes were significantly reinforced both in keratinocyte cultures (corneodesmosin, claudin, ZO-1) and in skin explants (desmoglein). DNA-array studies also demonstrated upregulation of genes involved in detoxification and anti-inflammation pathways. Proteomic studies revealed that hBD2 production was increased in keratinocytes in contact with SENKY, whereas IL-8, PGE-2 and TLR-9 releases were repressed as well as sebocyte lipid production. Clinical evaluations confirmed that after 3 weeks, SENKY significantly reduced dandruff intensity, redness, itching and scalp histamine content compared to placebo and beginning of treatment.

CONCLUSION

For the first time, SENKY has been shown to promote scalp homoeostasis by reinforcing barrier and defence functions at both gene and protein levels. It reduces irritation and redness in promoting detoxification and anti-inflammation pathways while controlling the niche of Malassezia. Applied on scalp, SENKY significantly reduces the formation of dandruff and soothes the scalp.

Incubatory environment of the scalp impacts pre-emergent hair to affect post-emergent hair cuticle integrity

OBJECTIVES

To determine whether the oxidative stress transmitted to newly grown hair from an unhealthy scalp has physical consequences to the cuticular condition and function.

METHODS

A uniquely designed 24-week clinical study included 8 weeks of pretreatment with a cosmetic shampoo and 16 weeks of treatment with either a potentiated zinc pyrithione (ZPT) antidandruff shampoo or a placebo cosmetic shampoo. This clinical design allowed the growth and acquisition of hair samples under conditions of varying but known scalp health as a result of treating a dandruff/seborrheic dermatitis (D/SD) population. Two complementary methods were used to characterize the integrity of the cuticular surface. Hair surface hydrophobicity was assessed by quantifying water wetting force using a Wilhelmy balance method. Surface structure and porosity were assessed using dynamic vapor sorption (DVS) to gravimetrically quantify water sorption.

RESULTS

Chemical oxidative stress to pre-emergent hair has been shown to have negative consequences to hair surface structure. Compared to a placebo shampoo control, use of a potentiated ZPT shampoo improved scalp health and significantly improved the following attributes associated with healthy hair: hair surface hydrophobicity (surface energy) and cuticular moisture barrier effectiveness (dynamic vapor sorption).

CONCLUSIONS

Pre-emergent hair can be negatively impacted by the oxidative stress that occurs with an unhealthy scalp, possibly due to metabolic activity of resident microbes. Manifestations of the oxidative stress include altered cuticle surface properties that are responsible for its protective function; these effects are similar in type to those observed by bleaching post-emergent hair. These alterations have the potential to make the hair, once emerged from the scalp, more susceptible to the cumulative physical and chemical insults responsible for hair feel and look, fiber integrity, and overall retention.

Efficacy and Safety of Cream Containing Climbazole/Piroctone Olamine for Facial Seborrheic Dermatitis: A Single-Center, Open-Label Split-Face Clinical Study

Background

Seborrheic dermatitis (SD) is a multifactorial disease; Malassezia species play an important role in its pathogenesis.

Objective

We aimed to determine whether a cream containing climbazole/piroctone olamine (C/P cream), antifungal agents with expected efficacy against Malassezia species, could improve SD symptoms.

Methods

We instructed 24 patients with mild-to-moderate SD to apply the C/P cream and emollient cream on the right and left sides of the face, respectively, every morning and evening for 4 weeks. The casual sebum level (measured with Sebumeter®; Courage & Khazaka Electronic GmbH, Germany) and the extent of erythema (measured with Mexameter®; Courage & Khazaka Electronic GmbH) on the face were measured at baseline and after 4 weeks. The minimal inhibitory concentration (MIC) was determined to demonstrate the antifungal activity of the C/P cream.

Results

The casual sebum level and erythema were measured at week 4, and the median values demonstrated a quantitative improvement on the C/P cream-treated right side of the face compared to the emollient cream-treated left side. For the C/P cream, the MICs were 0.625, 5, 0.625, and 2.5 mg/ml for Malassezia restricta, M. globosa, M. sympodialis, and M. slooffiae, respectively.

Conclusion

Based on the reduced casual sebum level and extent of erythema, the antifungal activity of C/P cream against Malassezia species seems useful for the treatment of mild to moderate SD.

Dysbiotic Bacterial and Fungal Communities Not Restricted to Clinically Affected Skin Sites in Dandruff

Dandruff is a prevalent chronic inflammatory skin condition of the scalp that has been associated with Malassezia yeasts. However, the microbial role has not been elucidated yet, and the etiology of the disorder remains poorly understood. Using high-throughput 16S rDNA and ITS1 sequencing, we characterized cutaneous bacterial and fungal microbiotas from healthy and dandruff subjects, comparing scalp and forehead (lesional and non-lesional skin sites). Bacterial and fungal communities from dandruff analyzed at genus level differed in comparison with healthy ones, presenting higher diversity and greater intragroup variation. The microbial shift was observed also in non-lesional sites from dandruff subjects, suggesting that dandruff is related to a systemic process that is not restricted to the site exhibiting clinical symptoms. In contrast, Malassezia microbiota analyzed at species level did not differ according to health status. A 2-step OTU assignment using combined databases substantially increased fungal assigned sequences, and revealed the presence of highly prevalent uncharacterized Malassezia organisms (>37% of the reads). Although clinical symptoms of dandruff manifest locally, microbial dysbiosis beyond clinically affected skin sites suggests that subjects undergo systemic alterations, which could be considered for redefining therapeutic approaches.

iTRAQ-based quantitative proteomics of stratum corneum of dandruff scalp reveals new insights into its aetiology and similarities with atopic dermatitis

The study aimed at detecting differentially expressed proteins in the stratum corneum of dandruff versus non-dandruff scalps to better understand dandruff aetiology. iTRAQ-based quantitative proteomic analysis revealed a total of 68 differentially expressed biomarkers. A detailed analysis of their known physiological functions provided new insights into the affected metabolic pathways of a dandruff scalp. Dandruff scalp showed (1) profound changes in the expression and maturation of structural and epidermal differentiation related proteins, that are responsible for the integrity of the skin, (2) altered relevant factors that regulate skin hydration, and (3) an imbalanced physiological protease-protease inhibitor ratio. Stratum corneum proteins with antimicrobial activity, mainly those derived from sweat and sebaceous glands were also found modified. Comparing our data with those reported for atopic dermatitis revealed that about 50 % of the differentially expressed proteins in the superficial layers of the stratum corneum from dandruff and atopic dermatitis are identical.

Treatment of Seborrhoeic Dermatitis in Asia: A Consensus Guide

Seborrhoeic dermatitis (SD) is common in Asia. Its prevalence is estimated to be 1-5% in adults. However, larger population-based studies into the epidemiology of SD in Asia are lacking, and the aetiology of SD may differ widely from Western countries and in different parts of Asia. In addition, clinically significant differences between Asian and Caucasian skin have been reported. There is a need to define standardized clinical diagnostic criteria and/or a grading system to help determine appropriate treatments for SD within Asia. With this in mind, experts from India, South Korea, Taiwan, Malaysia, Vietnam, Singapore, Thailand, the Philippines, Indonesia, and Italy convened to define the landscape of SD in Asia at a meeting held in Singapore. The consensus group developed a comprehensive algorithm to aid clinicians to recommend appropriate treatment of SD in both adults and children. In most cases, satisfactory therapeutic results can be accomplished with topical antifungal agents or topical corticosteroids. Non-steroidal anti-inflammatory agents with antifungal properties have been shown to be a viable option for both acute and maintenance therapy.