Objectives: This study aimed to evaluate the correlation between mast cell (MC) density in rosacea-affected skin and the expression of key inflammatory mediators, including IL-6, TNF-α, and cathelicidin LL-37. By comparing lesions rich in MCs with those having fewer MCs, we sought to elucidate the role of MCs in the inflammatory mechanisms underlying rosacea pathogenesis.

Methods: Specimens were collected from 20 patients diagnosed with rosacea who attended the outpatient clinic between 2008 and 2013. Each specimen underwent staining using hematoxylin/eosin, Giemsa, IL-6, LL-37, and TNF-α for both histopathological and immunohistochemical analyses. The number of stained cells was counted across 10 randomly selected dermal layers at a magnification of ×400 using light microscopy. The results were categorized based on the number of MCs counted: more than 10 MCs were classified as MC-rich, and 10 or fewer MCs as MC-poor.

Results: Among the 20 patients (10 MC-rich and 10 MC-poor), the MC-rich group demonstrated significantly higher MC counts than the MC-poor group (P<0.001). However, there were no significant differences in the expression levels of IL-6, LL-37, or TNF-α between the two groups. Additionally, MC density did not show any significant associations with patient demographics, clinical characteristics, or systemic comorbidities.

Conclusion: Increased MC density was not associated with differences in IL-6, TNF-α, or LL-37 expression in rosacea lesions. These findings suggest that MC infiltration may not directly influence the inflammatory mediator profile in rosacea. Further research is required to identify distinctive pathological features or markers that can elucidate the mechanisms of rosacea.

Objectives: This study aimed to evaluate the correlation between mast cell (MC) density in rosacea-affected skin and the expression of key inflammatory mediators, including IL-6, TNF-α, and cathelicidin LL-37. By comparing lesions rich in MCs with those having fewer MCs, we sought to elucidate the role of MCs in the inflammatory mechanisms underlying rosacea pathogenesis.

Methods: Specimens were collected from 20 patients diagnosed with rosacea who attended the outpatient clinic between 2008 and 2013. Each specimen underwent staining using hematoxylin/eosin, Giemsa, IL-6, LL-37, and TNF-α for both histopathological and immunohistochemical analyses. The number of stained cells was counted across 10 randomly selected dermal layers at a magnification of ×400 using light microscopy. The results were categorized based on the number of MCs counted: more than 10 MCs were classified as MC-rich, and 10 or fewer MCs as MC-poor.

Results: Among the 20 patients (10 MC-rich and 10 MC-poor), the MC-rich group demonstrated significantly higher MC counts than the MC-poor group (P<0.001). However, there were no significant differences in the expression levels of IL-6, LL-37, or TNF-α between the two groups. Additionally, MC density did not show any significant associations with patient demographics, clinical characteristics, or systemic comorbidities.

Conclusion: Increased MC density was not associated with differences in IL-6, TNF-α, or LL-37 expression in rosacea lesions. These findings suggest that MC infiltration may not directly influence the inflammatory mediator profile in rosacea. Further research is required to identify distinctive pathological features or markers that can elucidate the mechanisms of rosacea.

Objectives: This study aimed to evaluate the correlation between mast cell (MC) density in rosacea-affected skin and the expression of key inflammatory mediators, including IL-6, TNF-α, and cathelicidin LL-37. By comparing lesions rich in MCs with those having fewer MCs, we sought to elucidate the role of MCs in the inflammatory mechanisms underlying rosacea pathogenesis.

Methods: Specimens were collected from 20 patients diagnosed with rosacea who attended the outpatient clinic between 2008 and 2013. Each specimen underwent staining using hematoxylin/eosin, Giemsa, IL-6, LL-37, and TNF-α for both histopathological and immunohistochemical analyses. The number of stained cells was counted across 10 randomly selected dermal layers at a magnification of ×400 using light microscopy. The results were categorized based on the number of MCs counted: more than 10 MCs were classified as MC-rich, and 10 or fewer MCs as MC-poor.

Results: Among the 20 patients (10 MC-rich and 10 MC-poor), the MC-rich group demonstrated significantly higher MC counts than the MC-poor group (P<0.001). However, there were no significant differences in the expression levels of IL-6, LL-37, or TNF-α between the two groups. Additionally, MC density did not show any significant associations with patient demographics, clinical characteristics, or systemic comorbidities.

Conclusion: Increased MC density was not associated with differences in IL-6, TNF-α, or LL-37 expression in rosacea lesions. These findings suggest that MC infiltration may not directly influence the inflammatory mediator profile in rosacea. Further research is required to identify distinctive pathological features or markers that can elucidate the mechanisms of rosacea.

Objectives: This study aimed to evaluate the correlation between mast cell (MC) density in rosacea-affected skin and the expression of key inflammatory mediators, including IL-6, TNF-α, and cathelicidin LL-37. By comparing lesions rich in MCs with those having fewer MCs, we sought to elucidate the role of MCs in the inflammatory mechanisms underlying rosacea pathogenesis.

Methods: Specimens were collected from 20 patients diagnosed with rosacea who attended the outpatient clinic between 2008 and 2013. Each specimen underwent staining using hematoxylin/eosin, Giemsa, IL-6, LL-37, and TNF-α for both histopathological and immunohistochemical analyses. The number of stained cells was counted across 10 randomly selected dermal layers at a magnification of ×400 using light microscopy. The results were categorized based on the number of MCs counted: more than 10 MCs were classified as MC-rich, and 10 or fewer MCs as MC-poor.

Results: Among the 20 patients (10 MC-rich and 10 MC-poor), the MC-rich group demonstrated significantly higher MC counts than the MC-poor group (P<0.001). However, there were no significant differences in the expression levels of IL-6, LL-37, or TNF-α between the two groups. Additionally, MC density did not show any significant associations with patient demographics, clinical characteristics, or systemic comorbidities.

Conclusion: Increased MC density was not associated with differences in IL-6, TNF-α, or LL-37 expression in rosacea lesions. These findings suggest that MC infiltration may not directly influence the inflammatory mediator profile in rosacea. Further research is required to identify distinctive pathological features or markers that can elucidate the mechanisms of rosacea.

Objectives: This study aimed to evaluate the correlation between mast cell (MC) density in rosacea-affected skin and the expression of key inflammatory mediators, including IL-6, TNF-α, and cathelicidin LL-37. By comparing lesions rich in MCs with those having fewer MCs, we sought to elucidate the role of MCs in the inflammatory mechanisms underlying rosacea pathogenesis.

Methods: Specimens were collected from 20 patients diagnosed with rosacea who attended the outpatient clinic between 2008 and 2013. Each specimen underwent staining using hematoxylin/eosin, Giemsa, IL-6, LL-37, and TNF-α for both histopathological and immunohistochemical analyses. The number of stained cells was counted across 10 randomly selected dermal layers at a magnification of ×400 using light microscopy. The results were categorized based on the number of MCs counted: more than 10 MCs were classified as MC-rich, and 10 or fewer MCs as MC-poor.

Results: Among the 20 patients (10 MC-rich and 10 MC-poor), the MC-rich group demonstrated significantly higher MC counts than the MC-poor group (P<0.001). However, there were no significant differences in the expression levels of IL-6, LL-37, or TNF-α between the two groups. Additionally, MC density did not show any significant associations with patient demographics, clinical characteristics, or systemic comorbidities.

Conclusion: Increased MC density was not associated with differences in IL-6, TNF-α, or LL-37 expression in rosacea lesions. These findings suggest that MC infiltration may not directly influence the inflammatory mediator profile in rosacea. Further research is required to identify distinctive pathological features or markers that can elucidate the mechanisms of rosacea.

Background: Bullous pemphigoid (BP) is an autoimmune blistering disease driven by autoantibodies against BP180 and BP230. While type 2 inflammation plays a key role, the precise immune cell alterations and transcriptomic changes remain unclear. Objective: To characterize immune cell composition and transcriptomic changes in BP patients using fluorescence-activated cell sorting (FACS)-based immunophenotyping and RNA sequencing. Methods: A case-control study was conducted on 10 newly diagnosed, treatment-naive BP patients and six healthy controls. Disease activity was assessed using the Bullous Pemphigoid Disease Area Index (BPDAI). Peripheral blood mononuclear cells were isolated for FACS analysis to determine immune cell subsets. RNA sequencing was performed to identify differentially expressed genes (DEGs) and enriched pathways. Statistical analyses included t-tests, Mann-Whitney U tests, and correlation analysis. Results: FACS analysis revealed a reduction in CD4 + T cells, T helper 2 (Th2), and B cells in BP patients (p<0.05), alongside an increase in M2a-like monocytes (p<0.001). RNA sequencing identified 262 DEGs, with secretory leukocyte peptidase inhibitor (SLPI) and transmembrane protein 237 being the most significantly upregulated. Proline-serine-threonine phosphatase interacting protein 2 (PSTPIP2) and SAM domain, SH3 domain, and nuclear localization signals 1 (SAMSN1) positively correlated with BPDAI (p<0.001). Gene ontology analysis highlighted enrichment in inflammatory responses and neutrophil degranulation pathways. Conclusion BP patients show distinct immune dysregulation, including decreased CD4 + T cells, Th2, and B cells, increased M2a-like monocytes, altered gene expression profiles, and correlations between PSTPIP2, SAMSN1 and disease activity. These findings provide insights into pathogenesis and potential therapeutic targets of BP.

Background: Occupational contact dermatitis (OCD) is prevalent among hairdressers due to frequent exposure to chemicals like hair dyes and bleaching agents. Despite the risks, awareness among hairdressers remains low, leading to underreporting and inadequate preventive measures. Objective: This study evaluated hairdressers’ awareness of harmful hair dye ingredients, their experiences with OCD, and the association with product usage patterns. Methods: A cross-sectional study involving 100 hairdressers in Korea examined the relationship between work experience, product usage, and OCD. Chi-square tests and multivariate regression identified significant correlations. Results: Among the participants, 51% reported experiencing adverse skin reactions, with the hands being the most commonly affected area. Longer work experience as a hairdresser was significantly associated with the occurrence of adverse effects ( p=0.046). Notably, shampoo was identified as a suspected causative material significantly more often by the severe group compared to the non-severe group (28.0% vs. 3.8%, p=0.04). Conclusion Chemical exposure and frequent wet work contribute to high rates of OCD among hairdressers. Poor glove usage, especially during shampooing due to inconvenience, is a major risk factor. Raising awareness, promoting proper glove use, and improving workplace safety training are essential for reducing these skin conditions.

Since the role of the liver in metabolic dysfunction, including type 2 diabetes mellitus, was demonstrated, studies on non-alcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD) have shown associations between fatty liver disease and other metabolic diseases. Unlike the exclusionary diagnostic criteria of NAFLD, MAFLD diagnosis is based on the presence of metabolic dysregulation in fatty liver disease. Renaming NAFLD as MAFLD also introduced simpler diagnostic criteria. In 2023, a new nomenclature, steatotic liver disease (SLD), was proposed. Similar to MAFLD, SLD diagnosis is based on the presence of hepatic steatosis with at least one cardiometabolic dysfunction. SLD is categorized into metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction and alcohol-related/-associated liver disease, alcoholrelated liver disease, specific etiology SLD, and cryptogenic SLD. The term MASLD has been adopted by a number of leading national and international societies due to its concise diagnostic criteria, exclusion of other concomitant liver diseases, and lack of stigmatizing terms. This article reviews the diagnostic criteria, clinical relevance, and differences among NAFLD, MAFLD, and MASLD from a diabetologist’s perspective and provides a rationale for adopting SLD/MASLD in the Fatty Liver Research Group of the Korean Diabetes Association.

Background: Nickel is a leading cause of allergic contact dermatitis. Patients with nickel allergy may suffer from persistent dermatitis not only through contact with nickel-plated items but also through ingestion of nickel-containing food. Objective: This study aimed to evaluate the current nickel content in Korean food products and provide more up-to-date Korean nickel-restricted diets that would increase patient compliance. Methods: The most frequently consumed food items were selected with replicates. Food samples were prepared according to the practices of normal consumers. The solid specimens were finely ground, and the liquid specimens were homogenized using a sterilized mixer. Tea bags were brewed in 100 mL of distilled water at 100 °C for 5 minutes. Solid (0.5 g) and liquid (2 g) specimens were subjected to microwave-assisted nitric acid digestion using inductively coupled plasma-mass spectrometry. Results: In total, 147 samples were collected from different food categories, including plant-based products, animal-based products, packaged foods, and drinks. Cocoa powder had the highest concentration of nickel (1.56 mg/kg), which is consistent with the results of previous studies. Soy products such as fermented soybean paste (Doenjang) (1.16 mg/kg), fermented soybean with red chili paste (Ssamjang) (0.67 mg/kg), and tofu (0.37 mg/kg) had elevated concentration of nickel. Moreover, nut-derived products such as chocolate (1.10 mg/kg), ground coffee (0.86 mg/kg), almond (0.84 mg/kg), and peanuts (0.64 mg/kg) contained elevated nickel concentration. Conclusion The nickel content in food constantly changes depending on the food processing procedures and place of origin. Therefore, revising the nickel-restricted diet is necessary to enhance patients’ understanding of it and help reduce dietary nickel intake.

Nivolumab is a checkpoint inhibitor monoclonal antibody, designed to interact with the programmed death cell receptor-1, preventing the inhibitory signaling on cytotoxic T cells. Immune checkpoint inhibitors can lead to severe cutaneous immune-related adverse events (irAEs). A 54-year-old female with a breast cancer metastasis was referred to our clinic due to diffuse cutaneous lesions of crusted erythematous patches and multiple blisters for 2 weeks. Five months before presentation, she started nivolumab/eribulin immunotherapy. Skin biopsy showed subepidermal blistering with perivascular lymphohistiocytic infiltration with eosinophils. Direct immunofluorescence showed linear deposition of immunoglobulin G and C3 along the dermoepidermal junction, consistent with bullous pemphigoid.Temporal relationship between initiation of nivolumab and skin lesion suggested the diagnosis of nivolumab-induced bullous pemphigoid. Dermatologic toxicity is the most common irAEs associated with nivolumab, but nivolumab-induced bullous pemphigoid is rare. Given the widespread use of immunotherapy, it is important to document this case to develop proper management strategies.