Seborrheic dermatitis

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

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

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

INTRODUCTION

Seborrheic dermatitis (SD) poses significant treatment challenges due to its chronic nature and the side effects associated with long-term use of conventional therapies like topical corticosteroids. In the search for alternative treatments, exosomes, particularly those derived from rose stem cells (RSCEs), offer a promising avenue due to their potential in managing chronic skin conditions.

OBJECTIVE

This case report examines the efficacy of a topical moisturizer containing RSCEs in treating a patient with refractory SD, aiming to provide an alternative treatment pathway.

MATERIALS AND METHODS

A 40-year-old male with a long-standing history of SD, unresponsive to traditional treatments, underwent a novel treatment regimen. This regimen included an initial topical application of 2.5 mL of RSCEs followed by a maintenance phase involving the application of a RSCE-containing moisturizer. Clinical outcomes were assessed through the Patient's Global Assessment (PGA) and Investigator's Global Assessment (IGA) scores, along with evaluations of scaling and erythema.

RESULTS

Remarkable clinical improvement was noted as early as 1-day post-treatment, with significant reductions in redness, scaling, and itching. The patient experienced sustained relief throughout the 6-month follow-up, with a recurrence in the sixth month that was less severe than previous flare-ups. This demonstrated not only the efficacy of RSCEs in symptom management but also their potential in extending remission periods.

CONCLUSION

The chronic management of SD can benefit from innovative treatments like the RSCE-containing moisturizer, as shown in this case report. While the observed outcomes are promising, indicating substantial improvements in skin condition and symptom management, larger controlled studies are necessary to validate the therapeutic potential of exosome-containing moisturizers fully. This case underscores the need for alternative therapies in SD treatment, highlighting the role of exosomes as a viable option.

STITCH and Molecular Docking Analysis of Selected Wood Apple (Limonia acidissima) Constituents as Anti-Dandruff and Anti-Acne Agents

Background

Wood apple (Limonia acidissima) has been reported to possess various pharmacological activities. The present study aimed to evaluate the 11 selected constituents of Wood apple (L. acidissima) as potent anti-dandruff and anti-acne agents using a molecular docking approach.

Materials and Methods

The 11 selected constituents of Wood apple were studied on the molecular docking behavior of Malassezia globosa Lipase-1 and Cutibacterium acnes beta-keto acyl synthase-III enzymes by using the patchdock method. Furthermore, STITCH analysis was carried out to determine the ligand-protein interactions. STITCH analysis reveals that two ligands, namely, psoralen and umbelliferone, have exhibited interactions with both the M. globosa and P. acnes KPA 171202 proteins.

Results

The docking studies revealed that isopimpinellin and saponarin exhibited the highest (ACE) atomic contact energy (-162.32 and - 318.63 kcal/mol) with that of M. globosa Lipase-1 and C. acnes beta-ketoacyl synthase-III, respectively.

Conclusion

Thus, the present finding provides new knowledge for understanding the 11 selected ligands of Wood apple (L. acidissima) as potent anti-dandruff and anti-acne agents.

Hydroxypyridone anti-fungals selectively induce myofibroblast apoptosis in an in vitro model of hypertrophic scars

Hypertrophic scars are a common complication of burn injuries, yet there are no medications to prevent their formation. During scar formation, resident fibroblasts are transformed to myofibroblasts which become resistant to apoptosis. Previously, we have shown that hydroxypyridone anti-fungals can inhibit transformation of fibroblasts, isolated from hypertrophic scars, to myofibroblasts. This study aimed to investigate if these drugs can also target myofibroblast persistence. Primary human dermal fibroblasts, derived from burn scar tissue, were exposed to transforming growth factor beta-1 (TGF-β1) for 72 h to induce myofibroblast transformation. The cells were then incubated with three hydroxypyridone anti-fungals (ciclopirox, ciclopirox ethanolamine and piroctone olamine; 0.03-300 μM) for a further 72 h. The In-Cell ELISA method was utilised to quantify myofibroblast transformation by measuring alpha-smooth muscle actin (α-SMA) expression and DRAQ5 staining, to measure cell viability. TUNEL staining was utilised to assess if the drugs could induce apoptosis. When given to established myofibroblasts, the three hydroxypyridones did not reverse myofibroblast transformation, but instead elicited a concentration-dependent decrease in cell viability. TUNEL staining confirmed that the hydroxypyridone anti-fungals induced apoptosis in established myofibroblasts. This is the first study to show that hydroxypyridone anti-fungals are capable of inducing apoptosis in established myofibroblasts. Together with our previous results, we suggest that hydroxypyridone anti-fungals can prevent scar formation by preventing the formation of new myofibroblasts and by reducing the number of existing myofibroblasts.

Efficacy and Safety of Precision Cryotherapy to Treat Seborrheic Dermatitis of the Scalp

BACKGROUND

Recently, a new cryotherapy device that precisely controls skin temperature was developed. Precision cryotherapy (PC) can be a safe and alternative treatment modality for immune-related skin diseases that are difficult to treat by conventional cryotherapy because of serious adverse events.

OBJECTIVE

To evaluate the efficacy and safety of PC in scalp seborrheic dermatitis (SD).

METHODS

A single-arm, prospective trial was designed. Twenty-four patients with SD underwent 3 PC interventions 2 weeks apart. At the baseline, Week 6, and Week 8, overall improvements in Physician Global Assessment (PGA) and clinical severity scores were assessed. At each visit, the erythema index (EI) and transepidermal water loss were evaluated. The patients scored 9 subjective symptoms using a visual analog scale (VAS).

RESULTS

The itch VAS score decreased by 50.4% at Week 8. Blinded investigators reported improvement of PGA scores from 2.86 ± 0.62 to 1.66 ± 0.61 and clinical severity scores from 4.55 ± 1.30 to 2.45 ± 1.37. The average EI decreased by 19.6% at Week 8 ( p < .05).

CONCLUSION

This study not only demonstrated the efficacy and safety of PC in scalp SD but it also revealed insights for PC being a promising treatment modality in immune-related skin diseases.

Evaluation of a patient education platform for seborrheic dermatitis

Seborrheic dermatitis (SD) is a common, burdensome inflammatory skin disorder. Little is known about the identity and quality of videos patients consume on social media to better understand and manage SD. We evaluated three social media platforms-YouTube, TikTok, and Instagram-for content, quality, and popularity. Search terms "seborrheic dermatitis," "dandruff," "cradle cap," and "flaky scalp" identified videos on each platform. The first 50 videos for each keyword were analyzed. After screening, 147 YouTube, 132 Instagram, and 164 TikTok videos were included. Videos were characterized by upload source (healthcare provider/organization [HCP]/non-HCP), quality (accurate/misleading/non-informative), content (educational/personal xperience/entertainment/advertisement), and number of likes/views. Data were analyzed by chi square (categorical) or Kruskal-Wallis (continuous) tests. YouTube contained a higher proportion of videos vs. TikTok and Instagram that were made by HCPs (42.2/19.7/17.7%, respectively) and contained more accurate (52.4/28.0/32.9%), and educational (66.7/38.6/34.4%) content (p < 0.0001 for all). Non-HCPs were responsible for creating the majority of videos across platforms along with most inaccurate/non-informative (65.9/86.8/78.6%) and non-educational (56.5/75.5/71.1%) content (p < 0.0001 for all). Despite lower quality of content and information, TikTok videos had the highest mean views (2,418,872) and likes (184,395) (p < 0.0001 for all). HCP vs. non-HCP-made videos were viewed more frequently only on YouTube. Though views and likes were common for all inaccurate and entertainment/advertisement content, they were most characteristic of TikTok and Instagram (p < 0.0001). These results show a high volume of SD video consumption across all platforms, especially those with lower quality and less informative content, and significant content difference across platforms. Additional studies are needed to better characterize online SD educational content and optimize HCP-led video creation and patient video consumption.

A review on nonviral, nonbacterial infectious agents toxicity involved in neurodegenerative diseases

Neuronal death, decreased activity or dysfunction of neurotransmitters are some of the pathophysiological reasons for neurodegenerative diseases like Alzheimer's, Parkinson's and multiple sclerosis. Also, there is evidence for the role of infections and infectious agents in neurodegenerative diseases and the effect of some metabolites in microorganisms in the pathophysiology of these diseases. In this study, we intend to evaluate the existing studies on the role of infectious agents and their metabolites on the pathophysiology of neurodegenerative diseases. PubMed, Scopus, Google Scholar and Web of Science search engines were searched. Some infectious agents have been observed in neurodegenerative diseases. Also, isolations of some fungi and microalgae have an improving effect on Parkinson's and Alzheimer's.

Scalp Seborrheic Dermatitis: What We Know So Far

Scalp seborrheic dermatitis (SSD) is a prevalent chronic, relapsing inflammatory skin disease. The etiology is related to sebum production, bacterial proliferation - Staphylococcus sp., Streptococcus, and M. restricta - and host immunity factors - NK1+, CD16+ cells, IL-1, and IL-8. Trichoscopy features include mostly arborizing vessels and yellowish scales. New trichoscopic findings were described to guide the diagnosis as dandelion vascular conglomerate, "cherry blossom" vascular pattern, and intrafollicular oily material. Antifungals and corticosteroids constitute the essential therapy, but new treatments have been described. This article aims to review and discuss the etiology, pathophysiology, trichoscopy, histopathologic findings, main differential diagnoses, and therapeutic options of SSD.

Relationship between facial skin problems with a focus on inflammatory cytokines and the presence of Malassezia in 1-month-old infants

Infantile skin problems not only cause temporary pain and discomfort, but also have a long-term impact on health. Hence, the purpose of this cross-sectional study was to clarify the relationship between inflammatory cytokines and Malassezia fungal facial skin problems in infants. Ninety-six 1-month-old infants were examined. Facial skin problems and the presence of inflammatory cytokines in the forehead skin were assessed using the infant facial skin visual assessment tool (IFSAT) and the skin blotting method, respectively. Malassezia, a fungal commensal, was detected using forehead skin swabs, and its percentage in the total fungal population was analyzed. Infants with positive interleukin-8 signals were more likely to have severe facial skin problems (p = 0.006) and forehead papules (p = 0.043). No significant association between IFSAT scores and Malassezia was found, but infants with forehead dryness had a lower percentage of M. arunalokei in the total fungal population (p = 0.006). No significant association was observed between inflammatory cytokines and Malassezia in the study participants. Longitudinal studies on the development of facial skin problems in infants are warranted to investigate the involvement of interleukin-8 and devise preventive strategies in the future.

Efficacy and safety of oral isotretinoin in the treatment of moderate to severe seborrheic dermatitis: a retrospective study

BACKGROUND AND OBJECTIVES

Seborrheic dermatitis is a common, chronic, and recurrent inflammatory skin disease. There are few studies on oral isotretinoin in the treatment of seborrheic dermatitis. The aim of this research was to analyze the efficacy and safety of oral isotretinoin in the treatment of patients with moderate to severe seborrheic dermatitis.

METHODS

This was a retrospective study. All included patients were diagnosed as moderate to severe seborrheic dermatitis and treated with oral isotretinoin from January 2019 to December 2020. Symptom Scale of Seborrheic Dermatitis (SSSD) was used to evaluate the overall severity status of disease.

RESULTS

A total of 48 patients with moderate to severe seborrheic dermatitis were enrolled, of which 26 patients were treated with oral isotretinoin at a dose of 20 mg/day, and 22 patients were treated with oral isotretinoin at a dose of 10 mg/day. The duration of treatment was 2.42 ± 0.98 months (range: 2-6 months). The absolute SSSD values were 10.63 ± 1.02 for all 48 patients, 10.95 ± 1.15 and 10.30 ± 1.11 for patients with a dose of 20 and 10 mg/day, respectively. At the endpoint, there were no significant difference in SSSD values between the two groups (2.21 ± 0.24 vs. 2.35 ± 0.46, P = 0.18). The patients were satisfied with the two treatment schemes, and the difference was not statistically significant (P = 0.78). The most common side effect was cheilitis; however, no serious adverse events occurred in either group.

CONCLUSIONS

When considering efficacy and safety, oral isotretinoin can be used to treat patients with moderate to severe seborrheic dermatitis.

Genotypic Analysis of the Population Structure in Malassezia globosa and Malassezia restricta

The molecular characterization of Malassezia spp. isolates from animals and humans has not been thoroughly studied. Although a range of molecular methods has been developed for diagnosing Malassezia species, they have several drawbacks, such as inefficiency in differentiating all the species, high cost and questionable reproducibility. The present study aimed to develop VNTR markers for genotyping Malassezia isolated from clinical and animal samples. A total of 44 M. globosa and 24 M. restricta isolates were analyzed. Twelve VNTR markers were selected on seven different chromosomes (I, II, III, IV, V, VII and IX), six for each Malassezia species. The highest discriminatory power for a single locus was obtained with the STR-MG1 marker (0.829) and STR-MR2 marker (0.818) for M. globosa and M. restricta, respectively. After the analysis of multiple loci, 24 genotypes were noted among 44 isolates in M. globosa, with a discrimination index D of 0.943 and 15 genotypes were noted among 24 isolates in M. restricta, with a discrimination index D of 0.967. An endogenous infection was detected in two patients. Different genotypes of M. globosa strains colonized one patient. Interestingly, VNTR markers analysis revealed a carriage between a breeder and his dog in three cases for M. globosa and two for M. restricta. The FST (0.018 to 0.057) values indicate a low differentiation between the three populations of M. globosa. These results suggest a dominant clonal mode of reproduction in M. globosa. The typing of M. restricta showed a genotypic diversity of the strains, which can cause various skin pathologies. However, patient five was colonized with strains having the same genotype collected from different body parts (back, shoulder). VNTR analysis was capable of identifying species with high accuracy and reliability. More importantly, the method would facilitate monitoring Malassezia colonization in domestic animals and humans. It was shown that the patterns are stable and the method is discriminant, making it a powerful tool for epidemiological purposes.

Changing spectrum of hair and scalp disorders over the last decade in a tertiary medical centre

BACKGROUND

Hair- and scalp-related disorders (HSRDs) encompass a wide range of conditions that affect people of all ages.

OBJECTIVE

To evaluate the workload and trends in HSRDs at an outpatient dermatological clinic in a tertiary medical centre over a 10-year period.

METHODS

Medical records for HSRD visits to the outpatient dermatology clinic at the Sheba Medical Center, an Israeli tertiary care center, were reviewed between 1 January, 2010 and 31 December, 2020.

RESULTS

There were 10,396 HSRD visits with a new-to-follow-up visit ratio of 1:1.9. The annual number of HSRD visits, as well as their proportion out of all dermatological outpatient visits, have increased from 295 (1.24%) in 2010 to 1726 (9.44%) in 2020. The patients' mean age was 35.3 years (women 39.5 years, men 28.8 years), age range 1-87 years. Over the decade, there was a growing predominance of women with an average female-to-male ratio of 2:1. The winter season accounted for 28.7% of annual visits, followed by the autumn (25.6%), summer (24.3%) and spring (21.4%). The most prevalent HSRDs included androgenetic alopecia (30.6%), alopecia areata (19.3%), telogen effluvium (15.4%), non-scarring folliculitis (15.4%), seborrheic dermatitis (14.9%), lichen planopilaris (7.1%) and folliculitis decalvans (6.6%). Androgenetic alopecia demonstrated the highest increase over the decade examined (from 17% to 32%).

CONCLUSION

HSRDs account for a significant percentage of visits at a tertiary dermatology outpatient clinic. The number of HSRD visits has increased annually over the past decade. The recent advancement in diagnosis and treatment may account, at least in part, for the growing burden of HSRDs within dermatological ambulatory care.

Differential microRNA profiles in elderly males with seborrheic dermatitis

Seborrheic dermatitis (SD) is one of the most common skin diseases characterized by inflammatory symptoms and cell proliferation, which has increased incidence in patients older than 50 years. Although the roles of microRNAs (miRNAs) have been investigated in several diseases, miRNA profiles of patients with SD remain unknown. This study aimed to identify differentially expressed miRNAs (DEMs) in lesions of elderly male patients with SD. We used a microarray-based approach to identify DEMs in lesions compared to those in non-lesions of patients with SD. Furthermore, Gene Ontology and pathway enrichment analysis were performed using bioinformatics tools to elucidate the functional significance of the target mRNAs of DEMs in lesions of patients with SD. Expression levels of two miRNAs-hsa-miR-6831-5p and hsa-miR-7107-5p-were downregulated, whereas those of six miRNAs-hsa-miR-20a-5p, hsa-miR-191-5p, hsa-miR-127-3p, hsa-miR-106b-5p, hsa-miR-342-3p, and hsa-miR-6824-5p-were upregulated. Functions of the SD-related miRNAs were predicted to be significantly associated with typical dermatological pathogenesis, such as cell proliferation, cell cycle, apoptosis, and immune regulation. In summary, SD alters the miRNA profile, and target mRNAs of the DEMs are related to immune responses and cell proliferation, which are the two main processes in SD pathogenesis.

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.

Seborrheic Dermatitis in Older Adults: Pathogenesis and Treatment Options

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

Presence of Malassezia Hyphae Is Correlated with Pathogenesis of Seborrheic Dermatitis

Seborrheic dermatitis (SD) is a common, chronic, and relapsing skin disease. The roles of Malassezia spp. in the pathogenesis of SD are still not clear due to the lack of direct evidence for the existence of hyphae within affected skin tissues. We set out to elucidate if Malassezia mycelium contributes to the onset and development of SD and if Malassezia mycelium is correlated with the clinical severity of SD patients. We detected Malassezia hyphae in patients with SD using potassium hydroxide (KOH) and calcofluor white (CFW) staining. Fluorescent microscopy was performed for the analysis of fungal cell wall and morphological characteristics of Malassezia under CFW staining. Culture growth in modified Dixon agar was used for DNA extraction and sequencing, and Malassezia species were confirmed by a sequencing data BLAST search against the NCBI database. We demonstrated that Malassezia hyphae were positively correlated with the clinical severity of SD patients (P = 3.1738 × 10-11). All the patients responded well to antifungal treatment. There is no significant difference for species dominance across the variant groups. However, the exact molecular mechanisms of how Malassezia spp. affect SD need to be further explored. The results show that Malassezia spp. in the hyphal stage are restricted to SD patients compared with healthy controls, suggesting that the presence of Malassezia hyphae contributes to the pathogenesis of SD. The results highlight the importance of the antifungal therapy for the future treatment of SD patients. IMPORTANCE Our results support the proposal that the hyphal form of Malassezia could be one of the pathogenic factors that contribute to SD, which has been previously less well studied. This clinical observation paves the way for further investigations of the molecular mechanisms of Malassezia hyphal pathogenicity in SD.

The impact of clinical nutrition on inflammatory skin diseases

The influence of nutrition on the pathophysiology and clinical severity of inflammatory facial dermatoses such as acne, rosacea, seborrheic dermatitis, and perioral dermatitis has been controversially discussed for years. As part of a modern treatment approach, clinicians should provide patients with information on how their choice of diet might impact their dermatologic diagnosis and could potentially enhance therapeutic outcome. Recently, the concept of a gut-skin axis has gained momentum in the understanding of inflammatory dermatoses, with nutrition considered a contributing factor in this context. For example, gastrointestinal symptoms in rosacea patients may indicate a dysbiosis of the gut microbiome, treatment of which may also improve severity of the skin disease. New research efforts were recently made for acne patients addressing the clinical effects of omega-3 fatty acids and probiotics. In contrast, due to the limited data available, no comparable specific dietary recommendations can yet be made for seborrheic or perioral dermatitis. However, there are promising signs that clinical nutrition and dermatology will be more extensively interlinked in the future, both clinically and scientifically.

Insulin Resistance and Metabolic Syndrome in Patients with Seborrheic Dermatitis: A Case-Control Study

Background: Our knowledge of the systemic effects of seborrheic dermatitis (SD) as a chronic inflammatory skin disease remains limited. We aimed to evaluate metabolic syndrome (MS) and glucose metabolism disorders in patients with SD. Methods: The study includes 53 patients over the age of 18 diagnosed with SD and 50 age-, gender-, and body mass index-matched healthy controls. Demographic data, anthropometric measurements, blood pressure levels, family history of SD and metabolic disorder, smoking history, and severity of the disease in SD patients were obtained. Fasting plasma glucose, insulin, hemoglobin A1c, lipid profile levels, and two-hour plasma glucose in the oral glucose tolerance test (OGTT 2-h PG), homeostasis model assessment of insulin resistance (HOMA-IR), and presence of MS were determined. Results: Weight, waist circumference, family history of SD, family history of metabolic disorder, and smoking status were significantly higher in the SD group compared with the control group (P = 0.04, P = 0.007, P = 0.004, P = 0.004, and P = 0.048, respectively). The levels of fasting plasma insulin and triglyceride, HOMA-IR and OGTT 2-h PG were also significantly higher in the SD group than in the control group (P = 0.0001, P = 0.033, P = 0.0001, and P = 0.049, respectively). In addition, the number of those with insulin resistance was significantly higher in the group with SD (n = 31, 58.49%) than in the control group (n = 11, 22%) (P = 0.0001). Although the rate of MS was higher in patients with SD (n = 12, 22.64%) than the controls (n = 6, 12%), the difference was not significant (P = 0.155). Conclusion: Our findings suggest an association between SD and insulin resistance, which may be due to their common inflammatory pathogenesis. This may be an indicator of susceptibility to diabetes, and these patients can be followed up for conditions associated with insulin resistance and encouraged to adopt a healthy lifestyle.

The skin mycobiome of an astronaut during a 1-year stay on the International Space Station

Analysis of the skin mycobiome of an astronaut during a 1-year stay on the International Space Station (ISS) revealed an increased relative abundance of Malassezia restricta and level of Malassezia colonization, and the presence of Cyberlindnera jadinii and Candida boidinii, uncommon skin mycobiome taxa. Similar observations were made in astronauts during a 6-month stay on the ISS (Med Mycol. 2016; 54: 232-239). Future plans for extended space travel should consider the effect of high levels of Malassezia colonization over long periods on astronauts' skin, and the abnormal proliferation of uncommon microorganisms that may occur in closed environments such as the ISS.

Guinea pig seborrheic dermatitis model of Malassezia restricta and the utility of luliconazole

Seborrheic dermatitis (SD) is a multifactorial disease in which Malassezia restricta has been proposed as the predominant pathogenic factor. However, experimental evidence supporting this hypothesis is limited. A guinea pig SD model using a clinical isolate of M. restricta was used to elucidate the pathogenicity of M. restricta. Also, the efficacy of 1% luliconazole (LLCZ) cream, a topical imidazole derivative, against M. restricta was compared with that of a 2% ketoconazole (KCZ) cream in the same guinea pig model. Dorsal skin hairs of guinea pig were clipped and treated with M. restricta by single or repeated inoculations without occlusion. Skin manifestations were examined macroscopically and histologically. A quantitative polymerase chain reaction (PCR) assay was also performed for mycological evaluation. An inflammatory response mimicking SD occurred after repeated as well as single inoculation but not in abraded skin. The inflammation score attained its maximum on day 11 and persisted until day 52. The yeast form of the fungal elements was distributed on the surface of stratum corneum and around the follicular orifices, and an epidermal and dermal histological reaction was observed. Application of 1% LLCZ or 2% KCZ cream significantly improved the skin manifestations and decreased the quantity of M. restricta rDNA in the skin lesions. The efficacy of topical antifungal drugs suggested that M. restricta is a pathogenic factor contributing to SD.

Relationship between the skin barrier function of 2-week-old infants after bathing and facial skin problems during the first 6 weeks of life: A prospective observational cohort study

AIM

This study aimed to identify the relationship between the skin barrier function after bathing at 2 weeks of age and subsequent facial skin problems during the first 6 weeks of life.

METHODS

A prospective observational study was conducted from July 2017 to February 2018 on healthy newborns aged 2 weeks. Skin barrier function was evaluated before bathing and at 30 and 90 min after bathing by measuring transepidermal water loss (TEWL), stratum corneum hydration (SCH), sebum secretion, and skin pH. Infantile facial skin problems were assessed using skin condition diaries maintained by a parent for 4 weeks.

RESULTS

Analysis of the data from 56 infants showed that 29 infants (51.8%) experienced facial skin problems from 2 to 6 weeks of age. A lesser change in the sebum secretion on the forehead before bathing to 90 min after bathing and a higher SCH of the forehead before bathing were less likely to result in facial skin problems (adjusted odds ratio [AOR] = 0.98, 95% confidence interval [CI]: 0.97-0.99; AOR = 0.96, 95% CI: 0.92-0.99).

CONCLUSIONS

A greater change in the sebum secretion on the forehead before bathing to 90 min after bathing and a lower SCH of the forehead before bathing were associated with subsequent infantile facial skin problems, indicating that a better ability to recover after bathing is important to prevent facial skin problems. Future studies should identify factors that enhance the recuperative functions of infantile skin.

Herbal Therapy for the Management of Seborrheic Dermatitis: A Narrative Review

INTRODUCTION

Dandruff and Seborrheic Dermatitis (SD) are similar skin conditions with different degrees ofseverity. Since the current therapies cannot remove dandruff efficiently, herbal extracts with better effectiveness and fewer side effects are used in the pharmaceutical and cosmetic industries. Due to the adverse effects of chemical drugs, the use of natural products and traditional medicine has significantly increased over the past few decades. Therefore, in this review, we reported the herbs used as anti-dandruff agents in traditional medicine worldwide.

METHODS

The review was conducted on the literature available on the medicinal utility of certain plants as anti-dandruff agents using PubMed and Google Scholar and the following search terms: Dandruff and plants or medicinal plant and dandruff treatment, and essential oil and dandruff.

RESULTS

Since the current therapies cannotefficiently remove dandruff, herbal extracts with better effectiveness and fewer side effects are used in the pharmaceutical and cosmetic industries. Nowadays, there are numerous different types of herbal antidandruff shampoos. They are effective and safe without the side effects of chemical agents. Recently, herbal medicine has attracted a great deal of scientific attention. Clinical evidence on the therapeutic effects of herbal products has resulted in the study of far more herbs for their therapeutic roles.

CONCLUSION

Herbal therapy plays a significant role in the development of favorable therapeutics, either alone or in combination with conventional antibiotics. However, the major challenges in this regard include finding compounds with satisfactorily lower MICs, low toxicity, and high bioavailability for effective and safe use in humans and animals.

A Review of the Current Evidence Connecting Seborrheic Dermatitis and Parkinson’s Disease and the Potential Role of Oral Cannabinoids

Parkinson’s disease (PD) is a neurodegenerative disorder associated with multiple comorbidities, including seborrheic dermatitis (SD), which develops in more than half of PD patients. SD in patients with PD can be severe and frequently intractable by traditional topical therapy. Cannabinoids possess anti-inflammatory and neuromodulatory properties working within the intrinsic endocannabinoid system, the activation of which may alleviate the motor symptoms of PD. The effect of cannabinoids on SD is unknown. Here we explore the pathophysiological mechanisms and possible therapeutic role of oral cannabinoids in PD patients with SD, and review speculative mechanisms underlying the association of PD and SD. Current data supporting the use of cannabinoids in both PD and SD, as well as oral cannabinoid safety and tolerability, are presented. Cannabinoids may provide the possibility of simultaneous treatment of both SD and PD. Specific SD studies and additional safety data on oral cannabinoids are needed.

Seborrheic dermatitis: comparative effectiveness of standard and intermittent external therapy

Background. The chronic and recurrent nature of seborrheic dermatitis, its wide prevalence and multifactorial etiopathogenesis require a comparison of the effectiveness of different treatment strategies. Aim. In a randomized controlled trial to evaluate the effectiveness of standard and intermittent therapy with topical corticosteroids and activated zinc pyrithione (Skin-cap cream) in reducing the severity of clinical manifestations, the duration of remission of the disease, and compliance with treatment. Methods. The effectiveness of external therapy in patients with seborrheic dermatitis of the face and scalp was studied. All the examined patients had at least two episodes of exacerbation per year. Doctor's prescription Mometasone furoate cream 0.1% 1 time/day externally for 14 days, activated zinc pyrithione (Skin-cap cream) 2 times/day externally for 14 days, further 1 time a day 2 times a week for 14 days. Results. There was a comparable clinical effectiveness of antiinflammatory therapy in the short term with more stable results of intermittent therapy with the use of (Skin-cap cream) in the long term. Conclusions. Usage of activated zinc pyrithione (Skin-cap cream) according to the intermittent scheme in the treatment of seborrheic dermatitis of the face with the transition to the scalp is associated with long-term results. Safety of medicine allows to use it pro re nata by patients, e.g., in case of increased stress levels, diet incompliance, with no risks of adverse events, specific to topical corticosteroids, those increases treatment compliance.

Demodex folliculorum infestations in common facial dermatoses: acne vulgaris, rosacea, seborrheic dermatitis

Background

Demodex mites are found on the skin of many healthy individuals. Demodex mites in high densities are considered to play a pathogenic role.

Objective

To investigate the association between Demodex infestation and the three most common facial dermatoses: acne vulgaris, rosacea and seborrheic dermatitis.

Methods

This prospective, observational case-control study included 127 patients (43 with acne vulgaris, 43 with rosacea and 41 with seborrheic dermatitis) and 77 healthy controls. The presence of demodicosis was evaluated by standardized skin surface biopsy in both the patient and control groups.

Results

In terms of gender and age, no significant difference was found between the patients and controls (p > 0.05). Demodex infestation rates were significantly higher in patients than in controls (p = 0.001). Demodex infestation rates were significantly higher in the rosacea group than acne vulgaris and seborrheic dermatitis groups and controls (p = 0.001; p = 0.024; p = 0.001, respectively). Demodex infestation was found to be significantly higher in the acne vulgaris and seborrheic dermatitis groups than in controls (p = 0.001 and p = 0.001, respectively). No difference was observed between the acne vulgaris and seborrheic dermatitis groups in terms of demodicosis (p = 0.294).

Study limitations

Small sample size is a limitation of the study. The lack of an objective scoring system in the diagnosis of Demodex infestation is another limitation.

Conclusion

The findings of the present study emphasize that acne vulgaris, rosacea and seborrheic dermatitis are significantly associated with Demodex infestation. Standardized skin surface biopsy is a practical tool in the determination of Demodex infestation.

Serum zinc levels in seborrheic dermatitis: a case-control study

Background/aim

Malassezia colonization, sebaceous gland activity, hormones, immune system defects, environmental factors, and the interactions between these factors are thought to contribute to the pathogenesis of seborrheic dermatitis (SD). Zinc, an essential element, is involved in many biological processes including the ones that contribute to the development of SD. The aim of this study is to evaluate serum zinc levels in patients with SD.

Materials and methods

Forty-three patients with SD and 41 healthy controls were enrolled in the study. Disease activity was assessed by the Seborrheic Dermatitis Area and Severity Index by a single dermatologist. Serum zinc levels of all subjects were evaluated.

Results

Statistically significantly lower serum zinc levels were noted in SD patients than in the control group (79.16 ± 12.17 vs. 84.88 ± 13.59, respectively; P = 0.045).

Conclusion

The results of the study demonstrated that patients who had SD had lower levels of serum zinc levels than healthy subjects.

The effect of lid hygiene on the tear film and ocular surface, and the prevalence of Demodex blepharitis in university students

AIM

To evaluate the effect blepharitis lid cleansers have on the tear film and ocular surface, and to examine the prevalence of Demodex folliculorum in a young population.

METHODS

Forty-eight university students completed a randomised, controlled, investigator-masked, eight-week clinical trial. Three eyelid hygiene products were investigated: blepharitis eyelid cleanser (OCuSOFT® Lid Scrub® PLUS foam), diluted baby shampoo (10% Johnson's® No More Tears ®) and a tea-tree based face wash (dr.organic®). Cooled boiled water was used as a control. Subjects attended for four visits: baseline, two weeks, four weeks and eight weeks. At each visit, subjective symptoms, non-invasive tear break up time, ocular surface staining and Demodex folliculorum investigation were assessed to evaluate any positive or negative effect on the tear film and ocular surface. Osmolarity was also measured at baseline and week eight only.

RESULTS

The overall prevalence of Demodex folliculorum found at baseline was 15%. Subjective symptoms improved in all groups, including control. There was no significant difference in mean osmolarity between the groups or within each group after eight weeks. There was a significant increase in osmolarity inter-eye variability in the baby shampoo group (5.5 ± 5.4 vs 15.2 ± 9.5; p = 0.03). There was no significant change in non-invasive tear break up time or ocular surface staining demonstrated after eight weeks of eyelid hygiene.

CONCLUSION

A low prevalence of Demodex folliculorum can be found in a young population. All blepharitis lid cleansers used demonstrated subjective improvement in symptoms, with no negative effects on tear break-up time or ocular surface staining. The blepharitis eyelid cleanser and tea-tree based face wash revealed no adverse effect on mean osmolarity or inter-eye variability. Similarly, baby shampoo did not cause a significant increase in mean osmolarity, however, a significant increase in inter-eye variability was found; suggesting a possible increase in ocular surface inflammation.

Second-to-fourth digit ratio and seborrheic dermatitis in males: a cross-sectional study

BACKGROUND

Seborrheic dermatitis is a common disease characterized by the erythematous plaques with oily-yellow desquamation. Increased sebaceous gland activity by androgenic hormones has played a role in the etiology of the disease. The second-to-fourth digit (2D:4D) ratio is thought to be a marker of prenatal androgen exposure.

OBJECTIVES

To investigate the association between 2D:4D ratios and seborrheic dermatitis in a male population.

METHODS

Healthy male controls and patients with seborrheic dermatitis were included in this study. One hundred seborrheic dermatitis patients and 120 healthy controls, aged 17-59, were enrolled. A digital Vernier caliper was used to measure the finger lengths. Seborrheic dermatitis severity was assessed using the Seborrheic Dermatitis Area and Severity Index (SDASI).

RESULTS

The 2D:4D ratios of the patients (x = 0.977) were significantly lower than those of the controls (x = 1.050) for right hands (t = 6.948; p = 0.000; > 0.05). No similar relationship was found between the 2D:4D ratio for left hands (t = 0.901; p = 0.368; > 0.05). Seborrheic dermatitis severity was negatively correlated with 2D:4D ratios of right hands (r = -0.391; p = 0.000-0.05).

STUDY LIMITATIONS

One of the main limitations of this study was the small sample, which got a head of us from acquiring certain findings about the 2D:4D ratio and seborrheic dermatitis. The other limitation is that the patient selection did not reflect the general population, as a single clinic was studied.

CONCLUSION

To the authors' knowledge, this is the first study examining the relationship between 2D:4D ratios and seborrheic dermatitis. The result of this study may indicate a line of investigation and can support the theory of prenatal androgen exposure.

Malassezia and Parkinson's Disease

Parkinson's disease (PD) is a common debilitating neurodegenerative disease caused by a loss of dopamine neurons in the substantia nigra within the central nervous system (CNS). The process leading to this neuronal loss is poorly understood. Seborrheic dermatitis (SD) is a common benign inflammatory condition of the skin which mainly affects lipid-rich regions of the head and trunk. SD is caused by over proliferation of the lipophilic fungus Malassezia. PD and SD are strongly associated. The increased PD risk following an SD diagnosis (OR = 1.69, 95% CI 1.36, 2.1; p < 0.001) reported by Tanner and colleagues remains unexplained. Malassezia were historically considered commensals confined to the skin. However, many recent studies report finding Malassezia in internal organs, including the CNS. This raises the possibility that Malassezia might be directly contributing to PD. Several lines of evidence support this hypothesis. AIDS is causally associated with both parkinsonism and SD, suggesting that weak T cell-mediated control of commensal microbes such as Malassezia might contribute to both. Genetic polymorphisms associated with PD (LRRK2, GBA, PINK1, SPG11, SNCA) increase availability of lipids within human cells, providing a suitable environment for Malassezia. Four LRRK2 polymorphisms which increase PD risk also increase Crohn's disease risk; Crohn's disease is strongly associated with an immune response against fungi, particularly Malassezia. Finally, Malassezia hypha formation and melanin synthesis are stimulated by L-DOPA, which could promote Malassezia invasiveness of dopamine neurons, and contribute to the accumulation of melanin in these neurons. Although Malassezia's presence in the substantia nigra remains to be confirmed, if Malassezia play a role in PD etiology, antifungal drugs should be tested as a possible therapeutic intervention.

Novel Non-Steroidal Facial Cream Demonstrates Antifungal and Anti-Inflammatory Properties in Ex Vivo Model for Seborrheic Dermatitis

INTRODUCTION

Seborrheic dermatitis (SEBD) is a chronic, recurrent skin disorder that typically occurs as an inflammatory response to fungi of the genus Malassezia. The development of an ex vivo model that mimics the fungal proliferation and skin inflammation of SEBD would play an important role in screening formulations for their efficacy in treating SEBD.

METHODS

An ex vivo model for SEBD using human skin explants that had been mechanically manipulated to facilitate colonization of Malassezia furfur was developed. This model was used to evaluate the efficacy of a novel non-steroidal facial cream (NSFC) in inhibiting M. furfur proliferation and reducing inflammatory cytokine levels.

RESULTS

This model reproduced some of the key pathological features of SEBD, including M. furfur proliferation and inflammatory cytokine production. Topical application of NSFC facial cream reduced M. furfur counts by 92% (p < 0.05) and levels of interleukin 8 (IL-8) and tumor necrosis factor alpha (TNF-α) by 82% and 40%, respectively (p < 0.05, both).

CONCLUSION

The proposed ex vivo model for SEBD could be a useful tool to evaluate topical antifungal treatments. The novel NSFC tested in this study reduced M. furfur proliferation and inflammatory cytokine levels following topical application and may be helpful in the management of SEBD.

FUNDING

ISDIN.

Effects of a cream containing 5% hyaluronic acid mixed with a bacterial-wall-derived glycoprotein, glycyrretinic acid, piroctone olamine and climbazole on signs, symptoms and skin bacterial microbiota in subjects with seborrheic dermatitis of the face

Objective: A new cream formulation containing hyaluronic acid 5%, complexed with a mix of a bacterial-wall-derived glycoprotein and peptide glycan complex (EDS), has been recently developed. We evaluated in a prospective, assessor-blinded, 6-week study the efficacy and tolerability of EDS in the treatment of facial seborrheic dermatitis (SD) and the effects on skin microbiota.

Subjects and methods: Seventy-five subjects (mean age 46; 60 men) with moderate-severe SD of the face were enrolled. EDS cream was applied twice daily. The primary outcome was the evolution of the Investigator Global Assessment (IGA) score, evaluating erythema, scale/flaking, grade of seborrhea and itch. Superficial skin bacterial microbiome at baseline and after treatment was assessed, using the 16S rRNA gene methodology, in affected and non-affected face areas. Local tolerability was evaluated checking self-reported side effects at each visit.

Results: Baseline IGA scores (mean±SD) was 10±3. The use of EDS reduced IGA score significantly by 70% at week 3 and by 88% at week 6. An increase in the abundance of Cutibacterium acnes genera associated with a significant drop of Staphylococcus genera presence was detected in affected areas. The ratio of relative abundance of genera Cutibacterium/Staphylococcus increased significantly after treatment in affected areas. The product was very well tolerated.

Conclusion: Treatment with EDS applied twice daily for 6 consecutive weeks was associated with a reduction of the signs and symptoms of SD. Furthermore, after EDS cream treatment, a reequilibrating effect on facial skin microbiota was observed. The product was very well tolerated.

Comparison of efficacy and safety of atorvastatin 5% lotion and betamethasone 0.1% lotion in the treatment of scalp seborrheic dermatitis

Purpose: Seborrheic dermatitis (SD) is a chronic inflammatory skin disorder that mainly affects areas rich in sebaceous glands, such as the scalp. Although the exact cause of SD is not clearly understood, it seems that skin colonization with Malassezia fungus and the inflammatory responses of the immune system to this fungus play an important role in the pathology of SD. Recently a growing body of evidence has shown anti-inflammatory and anti-fungal effects of statins. Thus, this study aimed to evaluate the efficacy of topical atorvastatin in the treatment of scalp SD.

Patients and methods: In this double-blind, clinical trial, 86 patients with mild-to-moderate scalp SD were divided into either atorvastatin (n=45) or betamethasone groups (n=41) by block randomization method. In addition to the ketoconazole 2% shampoo (3 times per week), the atorvastatin group received atorvastatin 5% lotion and the betamethasone group received betamethasone 0.1% lotion daily for 4 weeks. The SD severity of each patient was determined by Symptom Scale of Seborrheic Dermatitis (SSSD) at baseline and 4 weeks after treatment. Also, the patient’s satisfaction of the treatment and adverse effects were investigated through individual reporting.

Results: After 4 weeks of treatment, the score of SD severity decreased significantly in both groups, while changes of SSSD score from baseline to the fourth week of treatment were comparable in the two groups (P-value=0.476). Regarding patient’s satisfaction of the treatment, results demonstrated the non-inferiority of atorvastatin as compared to betamethasone. Topical atorvastatin was also well-tolerated in almost all patients.

Conclusion: Although preliminary, the results of the present study showed that topical atorvastatin has a comparable effect to topical betamethasone and can be considered as an alternative therapeutic modality in the treatment of scalp SD. However, these results need to be confirmed in future studies while taking into consideration the improvement of topical statin formulations.

Clinical and instrumental evaluation of a new topical non-corticosteroid antifungal/anti-inflammatory/antiseborrheic combination cream for the treatment of mild-to-moderate facial seborrheic dermatitis

PURPOSE

Topical agents play a key role in the management of facial seborrheic dermatitis (SD) by reducing inflammation and scale production. The aim of this open-label trial was to assess the efficacy and tolerability of a new non-corticosteroid, antifungal/anti-inflammatory/antiseborrheic cream containing piroctone olamine, stearyl glycyrrhetinate, and zinc PCA in the treatment of facial SD using clinical and instrumental evaluation.

PATIENTS AND METHODS

Twenty adult subjects affected by mild-to-moderate inflamed facial SD were enrolled and instructed to apply the study cream twice daily for 60 days. Efficacy was evaluated at baseline, and at days 15, 30, and 60 by measuring the grade of desquamation, erythema, and pruritus using clinical evaluation, erythema-directed digital photography, colorimetry, and subject-completed Visual Analog Scale. Additionally, an Investigator Global Assessment (IGA) was assessed using a 5-point scale: excellent response (>80% improvement); good response (50%-80% improvement); mild response (<50% improvement); no response (no change); worsening.

RESULTS

After 15 days, a statistically significant decrease from baseline was found in desquamation, erythema, colorimetric scores, and pruritus. At day 60, a significant further improvement for all evaluated parameters was recorded. Moreover, the IGA improved in 90% of patients, with an excellent response in 53% of cases. A good correlation was found between clinical and instrumental evaluations.

CONCLUSION

Our results indicate that the study facial cream represents an option to consider when dealing with mild-to-moderate SD, being effective, well-tolerated, and free of significant side effects, as confirmed by clinical and instrumental evaluation.

Algal polysaccharides: potential bioactive substances for cosmeceutical applications

The cosmetics industry is one of the most profitable in the world today. This multi-billion-dollar industry has a profound sociological impact worldwide. Its influence is global, with most individuals being concerned with conserving their physical appearance, beauty, and youth. The consumers' desire for novel, better, and safer products has stimulated the utilization of natural-product-based cosmeceutical formulations over synthetic chemicals. With remarkable advancements in marine bioresource technology, algal polysaccharides have gained much attention as bioactive ingredients in cosmeceuticals. Algae biosynthesize a variety of polysaccharides including fucoidans, alginates, carrageenans, galactans, agar, porphyran, glucans, and ulvans, all of which exhibit distinctive structural and functional properties. Many of these materials have been proven to possess skin-protective effects, including anti-wrinkle, lightening, moisturizing, UV protective, antioxidative, and anti-inflammatory activity. Moreover, they have a wide spectrum of physicochemical properties, such as the ability to form hydrogels, which extend their utilization as emulsifiers, stabilizers, and viscosity controlling ingredients in cosmeceuticals. Accordingly, algal hydrocolloids and their synthetic derivatives can also be applied in tissue engineering and cosmetic surgery. The challenge is to increase awareness about these polysaccharides and consequently generate value-added products. This review discusses the beneficial biological and physicochemical properties of algal polysaccharides, highlighting their potential in cosmeceutical applications.

Association between Diet and Seborrheic Dermatitis: A Cross-Sectional Study

Current treatments for seborrheic dermatitis provide only temporary relief. Therefore, identifying modifiable lifestyle factors may help reduce disease burden. The objective of this study was to determine whether specific dietary patterns or total antioxidant capacity are associated with seborrheic dermatitis. Participants of the Rotterdam Study with a skin examination and a food frequency questionnaire were included. Total antioxidant capacity was assessed on the basis of ferric reducing antioxidant potential of each food item. Dietary patterns were identified with principal component analysis (PCA). Multivariable logistic regression analyses were used to assess the association between total antioxidant capacity, dietary pattern-derived PCA factors, and seborrheic dermatitis adjusted for confounders. In total, 4,379 participants were included, of whom 636 (14.5%) had seborrheic dermatitis. The PCA identified vegetable, Western, fat-rich and fruit dietary patterns. The fruit pattern was associated with a 25% lower risk (quartile 1 vs. quartile 4: adjusted odds ratio = 0.76, 95% confidence interval = 0.58-0.97, P = 0.03), and the Western pattern with a 47% increased risk (quartile 1 vs. quartile 4: adjusted odds ratio = 1.47; 95% confidence interval = 0.98-2.20, P = 0.03), but only for females. Other factors were not associated with seborrheic dermatitis. In conclusion, a high fruit intake was associated with less seborrheic dermatitis, whereas high adherence to a "Western" dietary pattern in females was associated with more seborrheic dermatitis.

Unilateral acne after facial palsy

We describe a case of unilateral acne which appeared after an episode of facial nerve palsy. An 18-year-old female patient presented with papules and pustules predominantly located on the side where the facial paralysis occurred. The patient suffered right facial paralysis, which was treated with prednisone and kinesiotherapy with massages, electrostimulation, and infrared light. Two weeks later, acne lesions appeared in the area affected by the paralysis. As suggested in other cases of paralysis, including cases of Parkinson's disease and spinal cord injury, an increased sebum excretion rate and the immobility of the affected area are most likely what caused the unilateral acne lesions.

Staphylococcus aureus is the most common bacterial agent of the skin flora of patients with seborrheic dermatitis

Background

Seborrheic dermatitis is an inflammatory skin disease that affects 1–3% of the general population. The Malassezia species has been implicated as the main causative agent; however, the bacterial flora of the skin may also play role in the etiopathogenesis. Therefore, we investigated the most common bacterial agent of the skin flora of patients with seborrheic dermatitis.

Materials and Methods

Fifty-one patients with seborrheic dermatitis and 50 healthy individuals are included in this study. Sterile cotton swabs were rubbed on the scalp of the participants for bacterial culture. Colonial morphology was identified with gram stain and catalase test.

Results

Staphylococcus aureus was isolated from 25 (49%) patients with seborrheic dermatitis and 10 (20%) healthy individuals within the control group. Coagulase-negative staphylococci were isolated from 24 (47.1%) patients with seborrheic dermatitis and 17 (34%) healthy individuals within the control group. Diphtheroids were present in 2 (3.9%) patients and 1 (2%) subject within the control group. Gram-negative bacilli were present only in 1 (2%) patient. Hemolytic streptococci and bacilli were identified in 1 (2%) subject from each group. Colonization of coagulase-negative staphylococci, diphtheroids, gram-negative bacilli, hemolytic streptococci, and bacillus did not differ between patients and healthy controls. However, S. aureus colonization was significantly more common in patients with seborrheic dermatitis than in healthy controls.

Conclusion

Within this study we revealed that S. aureus colonization was significantly higher among the patients. Therefore, we propose that, in addition to the Malassezia species, S. aureus may play a role in the etiopathogenesis of seborrheic dermatitis.

Differential diagnoses of diaper dermatitis

Diaper dermatitis is the most common contact eczema present in early childhood. The main cause is an irritant reaction to urine and feces, which is facilitated by the occlusive conditions under the diaper, leading to hyperhydration of the stratum corneum (diaper dermatitis). In addition, diaper pressure and friction can increase the risk of skin inflammation, which also opens the skin up to other irritant agents, allergens, and infectious agents, such as candida albicans. However, a variety of diseases are associated with inflammation of the skin in the diaper region, therefore the term "diaper dermatitis" is merely descriptive and does not reflect anything about the etiopathogenesis. The term diaper dermatitis refers only to an inflammation in the diapering area and should not be automatically equated with reactions to diapers. Making the correct diagnosis requires a thorough examination of the skin in its entirety and a detailed report of the patient's medical and family history. Once a specific pattern is identified, a precise diagnosis, and an appropriate therapy, can be determined.

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.