Search Results (103)

Skin diseases frequently coexist with other disorders, such as metabolic syndrome, diabetes mellitus, depression, psoriatic arthritis, and cardiovascular disease. Altered levels of distinct chemokines, like CCL5/RANTES, CXCL12/SDF-1a, CCL7/MCP-3, CCL2/MCP-1, CXCL1/GROa, and the eotaxin family, contribute to the development and/or exacerbation of inflammation, which is a common feature of numerous skin diseases as well as metabolic syndrome. The pathological and molecular connections between chronic inflammatory skin diseases and metabolic syndrome are increasingly recognized as being driven by shared inflammatory pathways, oxidative stress, and adipokine dysregulation. While systemic inflammation acts as a common thread, the precise mechanisms for some conditions remain partially understood. Nevertheless, the exact pathological and molecular connections between skin diseases (i.e., psoriasis, atopic dermatitis, pemphigus vulgaris, acute and chronic spontaneous urticaria, bullous pemphigoid, squamous cell carcinoma, alopecia areata, systemic sclerosis, discoid lupus erythematosus, diffuse large B-cell lymphoma) and metabolic syndrome are not yet fully understood. This narrative review summarizes the robust association between various chronic inflammatory skin diseases and metabolic syndrome in the context of pro-inflammatory chemokines. Full article

Anti-p200 pemphigoid is an autoimmune blistering disease (AIBD) caused by autoantibodies against laminin β4 and/or γ1, and clinically resembles bullous pemphigoid (BP) as well as the inflammatory variant of epidermolysis bullosa acquisita (EBA). All three diseases show IgG and/or C3 deposition along the cutaneous basement membrane zone (BMZ). Although complement activation is central to BP and EBA pathogenesis, its role in anti-p200 pemphigoid remains unclear. To investigate this, we analyzed inflammatory infiltrates in lesional and perilesional skin from anti-p200 pemphigoid patients (n = 11), revealing a neutrophil-predominant pattern, with mixed neutrophil–eosinophil infiltrates in 81% of cases, which contrasted with the eosinophil-rich infiltrates typical of BP. Infiltrating neutrophils expressed C5aR1 and C5aR2. Complement fixation test (CFT) of patient sera demonstrated C3c deposition at the BMZ in 40% (20/50) of anti-p200 pemphigoid cases and 87% (13/15) of BP cases. Patients in both cohorts could be stratified into high, mild, and non-complement-fixating groups. Pharmacological inhibition of C1s (sutimlimab), C3 (compstatin), C5 (tesidolumab), or C5aR1 (avacopan) significantly blocked C3c or C5 deposition in vitro. These findings indicate that selective blockade of the classical, alternative, or terminal complement pathways effectively prevents BMZ complement deposition, highlighting pathway-specific complement inhibition as a potential therapeutic strategy for anti-p200 pemphigoid. Full article

Bullous pemphigoid (BP) is the most common autoimmune subepidermal blistering disease. In recent decades, an increasing incidence of BP has been reported. The rationale for this study arises from the limited availability of advanced immunopathological and serological assays for assessing disease activity in bullous pemphigoid across many clinical centers. This systematic review evaluates evidence regarding hematological markers derived from complete blood count (CBC), such as eosinophil count and neutrophil-to-lymphocyte ratio (NLR), in BP patients. The Ovid MEDLINE and EMBASE databases were searched for English-language peer-reviewed papers published until 2 May 2025. Sixteen studies involving 1775 patients were included. Eosinophil count consistently correlated with disease severity, clinical phenotype, treatment response, and relapse risk, while NLR showed potential as a prognostic and therapeutic marker. Given their accessibility and cost-effectiveness, these parameters may have practical value in the routine clinical management of BP. Full article

Chronic inflammatory skin diseases and neurodegenerative disorders share overlapping genetic, immunologic, and metabolic pathways that may predispose individuals to cognitive decline. This review synthesizes current human genomic, transcriptomic, and bioinformatic evidence linking psoriasis, rosacea, atopic dermatitis, and bullous pemphigoid with Alzheimer’s and Parkinson’s disease. Literature from PubMed, IEEE Xplore, and Google Scholar was examined, prioritizing studies integrating genomic, transcriptomic, and proteomic analyses. Among inflammatory dermatoses, psoriasis exhibits the strongest overlap with dementia genetics, with shared susceptibility loci including APOE, IL12B, and HLA-DRB5, and transcriptional regulators such as ZNF384 that converge on IL-17/TNF signaling. Rare-variant and pleiotropy analyses further implicate SETD1A and BC070367 in psoriasis–Parkinson’s comorbidity. Rosacea demonstrates upregulation of neurodegeneration-related proteins SNCA, GSK3B, and HSPA8, together with shared regulatory hubs (PPARG, STAT4, RORA) driving NF-κB/IL-17/TNF-dependent inflammation. In atopic dermatitis, rare FLG variants interacting with BACE1 suggest a mechanistic bridge between barrier dysfunction and amyloidogenic processing. Bullous pemphigoid reveals an HLA-DQB1*03:01-mediated immunogenetic link hypothesis and cross-reactive autoantibodies targeting BP180 (collagen XVII) and BP230, highlighting an autoimmune route of neurocutaneous interaction. Other inflammatory and neurodegenerative diseases with currently weak or limited genetic evidence are also discussed, as they may represent emerging biological pathways or potential therapeutic targets within the skin–brain connection in the future. The aim of this work is to help clarify these genetic links and to advocate for the routine cognitive assessment of affected patients, enabling early detection, improved long-term quality of life, and the potential for timely therapeutic intervention. Full article

Bullous pemphigoid (BP), the most prevalent autoimmune blistering skin disorder, has been associated with dipeptidyl peptidase-4 inhibitor (DPP4i) treatment in type 2 diabetic patients. This study aimed to investigate the association of DPP4 gene variants, rs3788979 and rs12617656, with classic BP (cBP)- and DPP4i-associated BP predisposition. Fifty-six (56) unrelated patients with cBP, 32 DPP4i-associated BP patients, 60 healthy controls, and 49 diabetic patients receiving DPP4i were included. Genotyping was performed using polymerase chain reaction-restriction fragment length polymorphism assay (PCR-RFLP). Statistical analyses were conducted using SPSS software. For rs3788979, the CT+TT genotypes were significantly associated with increased risk of DPP4i-associated BP compared with cBP [(Odds Ratio (OR) = 2.80, 95% Confidence Interval (CI) = 1.07–7.35; p-value = 0.034] and healthy controls (OR = 0.30, 95% CI = 0.13–0.86; p-value = 0.020). The T allele was also enriched in DPP4i-associated BP (OR = 2.57, 95% CI = 1.09–6.07; p-value = 0.027). Additionally, the TC genotype of rs12617656 (OR = 2.29, 95% CI = 1.04–5.03, p-value = 0.039) showed significant association with cBP susceptibility. These findings highlight DPP4 variants as potential BP risk factors, supporting personalized risk assessment prior to initiating gliptin therapy. Large-scale studies are warranted to validate these associations. Full article

Background/Objectives: Bullous pemphigoid (BP) is an autoimmune blistering skin disease. The association between dipeptidyl peptidase 4 inhibitors (DPP-4 inhibitors) and bullous pemphigoid (BP) has been studied in many countries; however, controversy has arisen from analyzing the related risk factors. The objectives of this study are to assess whether the association between DPP-4 inhibitors and bullous pemphigoid in EudraVigilance is statistically significant and to identify the presence of risk factors found in previous studies in a case/exposure group. Our results will be compared with those obtained from the Food and Drug Administration Adverse Event Reporting System database (FAERS). Methods: A case/control retrospective observational study was performed using data from the European database EudraVigilance. All reports from 2007 to 2024 (a total of 11,451,738 reports) were gathered and filtered by exposure to DPP-4 inhibitors and development of BP or lack thereof. Association was measured using reporting odds ratios with a 95% confidence interval, and Fisher’s exact test was used to obtain p-values, assuming an alpha error of 0.05. Results: The results indicate an association between the consumption of DPP-4 inhibitors and the development of BP (with an odds ratio of 153.5; 95% confidence interval 144.1–163.5; ROR = (a/c)/(b/d); a: 1345 reports of BP associated with DPP-4i; c: 3870 reports of BP associated with other different drugs; b: 25,857 reports of other ADRs and DPP-4i; and d: 11,420,666 reports of ADRs associated with other drugs). The predominant factors in the case/exposure group were male gender (58.6%), age between 65 and 85 years (43.3%), medical history of type 2 diabetes mellitus (30.4%) and consumption of vildagliptin (44.2%). Similar results were found in a prior analysis of the FAERS database (2006–2020). Conclusions: This study provides evidence of the association between the consumption of gliptins and the development of BP. Disproportionality measures were estimated to be higher in the exposure group than in the positive controls. As such, BP could appear after several months of exposure, and dermatological monitoring is crucial. Full article

The adaptor molecule DNAX-activating protein of 12 kDa (DAP12) is broadly expressed in innate immune cells, but its role in autoimmunity remains unclear due to its dual regulatory functions. We investigated the contribution of the DAP12 pathway to bullous pemphigoid (BP), the most common autoimmune blistering disease, using a mouse model induced by transfer of anti-type XVII collagen (Col17) IgG. Repeated anti-Col17 IgG injections over 12 days produced comparable disease activity in DAP12-deficient and wildtype mice (n = 17/group), indicating that disease induction occurs independently of DAP12 signaling. Flow cytometry and immunofluorescence analysis of lesional skin further revealed a strong upregulation of the DAP12-associated triggering receptors expressed on myeloid cells (TREM) 1 in wildtype BP lesions, whereas TREM2⁺ cell frequencies in anti-Col17 IgG-treated wildtype and DAP12 knock-out animals were significantly lower than in healthy controls. Additional flow cytometry analysis demonstrated altered inflammatory infiltrates with notably reduced frequencies of Siglec-f⁺ eosinophils in DAP12-deficient vs. wildtype lesional skin. In addition, pharmacological inhibition of PI3Kδ, a downstream kinase of the DAP12/TREM pathway, did not affect disease progression in anti-Col17 IgG-induced BP. Collectively, these findings indicate that while DAP12 signaling modulates local immune cell composition, the DAP12/TREM1/2-axis does not influence overall disease activity in experimental BP. Full article

T helper 2 (Th2)-mediated dermatoses are inflammatory skin diseases driven by CD4⁺ Th2 cells that produce interleukin (IL)-4, IL-5, IL-13, and IL-31, promoting immunoglobulin E (IgE) class switching, eosinophil recruitment, mast cell degranulation, and pruritus. We aimed to place these conditions in context and clarify how Th2 biology informs diagnosis and therapy. We conducted a narrative synthesis of mechanistic, translational, and clinical evidence on Th2 pathways in atopic dermatitis (AD), prurigo nodularis, bullous pemphigoid, chronic spontaneous urticaria, and selected type I/IVb hypersensitivity reactions, with focused appraisal of trials targeting IL-4Rα, IL-13, and IL-31R. Persistent Th2 activation is associated with epidermal barrier dysfunction, immune dysregulation, and pruritogenic neural signaling; AD is the archetype, showing prominent lesional IL-4/IL-13 activity correlated with severity and itch. Across disorders, pathway-directed biologics against IL-4Rα, IL-13, and IL-31R consistently reduce disease activity and pruritus in AD and prurigo nodularis, with emerging signals of benefit in bullous pemphigoid and chronic spontaneous urticaria. The Th2 axis provides a unifying pathogenic framework and actionable therapeutic target across multiple dermatoses. Integrating cytokine profiling with clinical phenotypes may refine patient stratification and optimize the deployment of existing and next-generation Th2-targeting therapies. Full article

Background and Objectives: While pemphigus vulgaris (PV) and bullous pemphigoid (BP) have been linked to autoimmune comorbidities, the spectrum and specificity of these associations remain uncertain. We aimed to investigate the prevalence and patterns of autoimmune diseases (AIDs) in patients with PV and BP compared with age- and sex-matched controls. Materials and Methods: We conducted a bicenter, retrospective case–control study including 287 PV patients with 1148 matched controls and 284 BP patients with 1137 matched controls. Autoimmune comorbidities were identified through medical record review, and disease-specific as well as system-level associations between PV, BP, and AIDs were assessed. Results: Overall AID prevalence was lower in PV (9.4%) and BP (8.1%) than in controls (18% and 15%, respectively; p < 0.001 and p = 0.002). PV was associated with Graves’ disease (adjusted OR: 3.16, 95% CI: 1.24–8.06), especially in females. BP was associated with Hashimoto thyroiditis (adjusted OR: 2.51, 95% CI: 1.33–4.75), particularly in males. System-level analyses revealed that cutaneous and multisystem AIDs were less frequent in both PV and BP (p < 0.001 for each and p = 0.001 for each, respectively), whereas endocrine AIDs were more frequent in BP (p = 0.038). Thyroid antibody positivity did not differ significantly between patients and controls. Limitations include retrospective design, possible overrepresentation of cutaneous AIDs in dermatology-based controls, and lack of external validation. Conclusions: Our findings suggest that PV and BP may be associated with selective, sex- and phenotype-specific autoimmune comorbidity patterns rather than a generalized autoimmune burden. Further prospective studies are needed to confirm these exploratory associations and clarify their temporal relationships. Full article

Tamibarotene (AM80) is an agonist of retinoic acid receptor alpha. It is licensed in Japan for the treatment of acute promyelocytic leukemia. Results from preclinical models suggest that tamibarotene might also be effective in the treatment of diverse autoimmune diseases. The effect of tamibarotene on autoimmune diseases of the skin, however, has not been explored. We therefore examined the effect of tamibarotene on disease in the antibody-transfer mouse model of bullous pemphigoid (BP)-like epidermolysis bullosa acquisita (EBA), a prototypical example for pemphigoid diseases. Pemphigoid diseases are a group of autoimmune blistering skin diseases driven by autoantibodies and the recruitment and activity of granulocytes in the dermis. In sharp contrast to its effect in models of other autoimmune diseases, tamibarotene aggravated EBA pronouncedly. At the peak of disease, skin inflammation in tamibarotene-treated mice involved, on average, 1.6-fold more of the total body surface compared to vehicle-treated mice. Tamibarotene markedly reduced the recruitment of regulatory T cells (T_regs) into the dermis. This blunted the counterregulatory mechanisms that normally curb skin inflammation in this model. The effect aligns with previous reports describing tamibarotene-mediated downregulation of skin-homing receptors on T_regs. In addition, tamibarotene prolonged the responsiveness of aging neutrophils to immune complexes in vitro, providing another mechanism that may exacerbate EBA. Collectively, our results suggest that tamibarotene may elicit detrimental effects in patients with EBA by abolishing the recruitment of T_regs into skin. This warrants great caution when using tamibarotene in patients with EBA and possibly other pemphigoid diseases. Full article

Background/Objectives: Bullous pemphigoid (BP) is a manageable condition, and the primary goal of treatment is to control the disease while minimizing the use of corticosteroids due to their potential side effects with long-term use. The primary aim of this study was to assess the effectiveness of omalizumab (OMZ) treatment in bullous pemphigoid patients using both objective and subjective indicators, including bullous pemphigoid disease area index (BPDAI) score, peripheral eosinophil count, serum total IgE level, systemic corticosteroid dosage, and pruritus severity (VAS pruritus). The secondary aim was to explore potential predictors of treatment response, such as baseline BPDAI, age, gender, lesion distribution, serum total IgE, peripheral eosinophil count, maximum and minimum corticosteroid dose, and comorbidities, as well as to evaluate the time to clinical response and corticosteroid tapering. Methods: This retrospective analysis included 25 BP patients treated with OMZ as add-on therapy to systemic corticosteroids between January 2023 and December 2024 at Health Sciences University, Başakşehir Çam and Sakura Training and Research Hospital, Dermatology and Venerology Clinic. No other systemic immunosuppressants were permitted. All patients were already receiving systemic corticosteroids at enrolment. This retrospective analysis included 25 BP patients receiving omalizumab (300 mg/4 weeks) as an add-on to systemic corticosteroids, initiated primarily for steroid-refractory disease and/or persistent, sleep-disrupting pruritus. Baseline was defined immediately before the first OMZ dose; assessments were performed at baseline and week 12. Clinical (BPDAI, VAS pruritus) and laboratory (eosinophil count, total IgE levels) parameters were assessed at baseline and week 12. Results: OMZ treatment significantly reduced disease severity, as evidenced by a mean decrease in the BPDAI score of 105.0 ± 48.9 (95% CI 84.8–125.2) compared to baseline (p < 0.001). Peripheral eosinophil count also decreased by 0.6 ± 0.3 (95% CI 0.4–0.7) after treatment (p < 0.001). Total serum IgE levels declined significantly in 92% of patients (95% CI 244.5–2171.3) compared to pretreatment (p < 0.001), although two patients (8%) showed an increase (202.0 ± 258.8) after OMZ treatment. OMZ treatment led to a mean systemic corticosteroid dose reduction of 37.0 ± 14.1 mg (95% CI 31.1–42.8 mg), with a median corticosteroid tapering time of 4 weeks (3.0–4.0). Additionally, pruritus severity, measured by pruritus VAS, decreased by 6.2 ± 1.4 (95% CI 5.6–6.7) following treatment (p < 0.001). OMZ was well tolerated, with no serious adverse events. Conclusions: Within a 12-week observation window, we observed improvements in disease activity and pruritus alongside reduced corticosteroid exposure. Given the retrospective, uncontrolled add-on design, these findings do not establish causality but support further prospective controlled evaluation of omalizumab as a steroid-sparing option. Importantly, OMZ treatment significantly reduced the mean corticosteroid dose, pruritus VAS score, total IgE levels, and eosinophil count, indicating therapeutic activity and supporting its use as an effective steroid-sparing option in the management of bullous pemphigoid. Full article

Background/Objectives: Anti-p200 pemphigoid is a rare and likely underdiagnosed autoimmune blistering disorder. Laminin γ1 and laminin β4 have been implicated as potential target antigens in its pathogenesis. Recently, a novel indirect immunofluorescence assay targeting anti-laminin β4 antibodies has been developed, demonstrating high sensitivity and specificity, and offering a valuable tool for improved diagnosis. Methods: Of the 451 patients, 21 were selected for further laboratory analysis based on medical records. Sera from 10 patients, which showed a positive direct immunofluorescence (DIF) result and negative results in multiplex enzyme-linked immunosorbent assays (ELISAs) and/or mosaic six-parameter indirect immunofluorescence (IIF) for various autoimmune bullous diseases, were tested for the presence of anti-laminin β4 antibodies. Additionally, sera from 11 patients with positive DIF and positive ELISA for antibodies against BP180 and/or BP230 were analyzed. Results: Among the 10 patients with positive DIF and negative ELISA and/or mosaic six-parameter IIF, 6 sera were positive for anti-laminin β4 antibodies. These patients presented with atypical clinical features. In contrast, all 11 sera from patients with both positive DIF and positive ELISA for BP180 and/or BP230 were negative for anti-laminin β4 antibodies. Conclusions: In patients with a positive DIF result but negative ELISA and/or mosaic six-parameter IIF findings, testing for anti-laminin β4 antibodies should be considered. Furthermore, in cases presenting with atypical clinical features—such as acral distribution of lesions, intense pruritus, or erythematous–edematous plaques—the possibility of anti-p200 pemphigoid should be included in the differential diagnosis. Full article

Bullous pemphigoid (BP) and pemphigus vulgaris (PV) represent the most prevalent conditions among autoimmune bullous skin diseases, considered a major cause of severe morbidity and, in certain cases, mortality. The hallmark of the two diseases is the presence of autoantibodies directed against proteins located in the basement membrane of the skin, which determines the formation of blisters. In recent years, interest in the role of microbiota in relation to health-disease status has progressively increased. In particular, based on the gut–skin axis, accumulating evidence has emerged on the potential association between the composition and diversity of microbial communities in the gut, skin, and even in the oral cavity and the risk of developing BP and PV. Dysbiosis, characterized by a generally higher relative abundance of Firmicutes and a depletion of probiotics/beneficial species, might contribute to the pathogenesis of both diseases. Despite the still limited number of studies and the need for further large-scale multicenter studies, the knowledge gathered so far is suggestive of a novel modifiable risk factor representing a potential target for adjuvant treatments of these disabling and life-threatening conditions. Full article

Background/Objective: Bullous Pemphigoid (BP) is a well-recognized autoimmune subepidermal blistering disease. However, its occurrence following allogeneic hematopoietic stem cell transplantation (HSCT) is extremely rare. The objective of this study is to systematically review the available data on BP following an allogeneic HSCT with focus on treatment options. Methods: A systematic review of studies evaluating BP following allogeneic HSCT, incorporating a highly treatment-resistant case from our graft-versus-host disease (GvHD) dermatology clinic, of a 47-year-old patient, notable as the only reported instance of BP following HSCT in a patient with chronic lymphocytic leukemia (CLL) that transformed into diffuse large B-cell lymphoma (DLBCL) and GvHD due to HSCT. The review yielded 15 publications that met the eligibility criteria. Including our case, a total of 16 cases were analyzed. Results: Nearly all patients (14/16) in this review had chronic GvHD due to their HSCT. Twelve patients were males, and six were of Japanese origin. The mean age for BP diagnosis was 38 years (a range of 5–67). On average, BP developed one year post-HSCT. The most common treatment for BP in these patients was prednisolone, with the majority experiencing complete resolution of symptoms. Conclusions: BP following HSCT is an exceptionally rare condition with an unclear underlying mechanism. Full article

Background/Objectives: Cutaneous side effects are the most common immune-related adverse events (irAEs) caused by immune checkpoint inhibitors (ICIs) and affect 70–90% of patients. Besides diverse types of exanthema, rare skin toxicity includes bullous dermatoses in 0.3% of cases. Systemic steroids are the first-line treatment for immune-related bullous pemphigoid (irBP); however, some cases are corticosteroid-resistant. IrBP is one of the irAEs most frequently chronic and associated with long-term steroid use. However, steroids may interfere with tumor response. Therefore, alternative treatment strategies for irBP are desperately needed. Dupilumab, a monoclonal antibody blocking the receptor binding of interleukin-4 (IL-4) and interleukin-13 (IL-13), has been successfully used to treat spontaneous forms of bullous pemphigoid (BP). In this study, we analyzed the gene expression profiles of BP and irBP. Patients and Methods: A retrospective multicenter study evaluated the gene expression profiles of irBP and BP in comparison to healthy controls. Gene expression analyses of skin biopsies were performed using NanoString technology from patients with BP (n = 17), irBP (n = 19), and healthy skin (n = 24) after the patients had consented to participate in this study, and differentially expressed genes (DEGs) were determined using Rosalind software. Results: Compared to healthy skin, BP showed 167 DEGs, and irBP revealed 99 DEGs. Some of the DEGs from irBP and BP vs. healthy skin overlapped. Specifically, IL-4- and IL-13-associated genes were upregulated in both irBP and BP compared to healthy skin. Interestingly, expression profiles of BP vs. irBP also showed 13 DEGs. Conclusions: These findings suggest a possibility for therapeutic efficacy of IL-4 and IL-13 inhibitors in the treatment of irBP. Full article