Background: Chronic spontaneous urticaria (CSU) is a common and disabling disease. Assessments of IgE and C‐reactive protein (CRP) are recommended in the diagnostic work‐up, but the role and clinical relevance of these biomarkers are not well characterized. Moreover, it remains unknown if elevated levels of IgE or CRP are linked to CSU microRNA (miRNA) signatures or interleukin 31 (IL‐31).Methods: We measured IgE and CRP serum levels in 47 CSU patients (and 45 healthy controls) and determined CSU disease activity using the urticaria activity score (UAS7). Expression levels of miR‐155 and miR‐221 were assessed by RT‐PCR, and IL‐31 levels were determined by ELISA.Results: Total IgE and CRP levels were independently increased in CSU patients. IgE and CRP levels were highest and lowest in patients with high and mild disease activity. IgE levels correlated with miR‐155 levels, whereas CRP levels correlated with miR‐221 levels. miR‐155 and miR‐221 were significantly overexpressed in CSU patients. ROC analyses linked miRNA‐155 and CSU with a sensitivity of 79% and specificity of 87%, and miRNA‐221 and CSU with a sensitivity of 75% and specificity of 91%. High CRP and miR‐221 expression levels were linked to elevated levels of IgG anti‐TPO and IL‐31.Conclusion: IgE and CRP are useful biomarkers for disease activity in CSU, with distinct miRNA profiles. High CRP and miR‐221 levels may point to autoimmune CSU and a role for IL‐31.

Introduction: Dermoscopy has become widespread in the diagnosis of inflammatory skin diseases. Cutaneous vasculitis (CV) is characterized by inflammation of vessels, and a rapid and reliable technique is required for the diagnosis. Objectives: We aimed to define CV dermoscopic features and increase the diagnostic accuracy of dermoscopy with machine learning (ML) methods. Methods: Eighty-nine patients with clinically suspected CV were included in the study. Dermoscopic images were obtained before biopsy using a polarized dermoscopy. Dermoscopic images were independently evaluated, and interobserver variability was calculated. Decision Tree, Random Forest, and K-Nearest Neighbors were used as ML classification models. Results: The histopathological diagnosis of 58 patients was CV. Three patterns were observed: homogeneous pattern, mottled pattern, and meshy pattern. There was a significant difference in background color between the CV and non-CV groups (P = 0.001). The milky red and livedoid background color were specific markers in the differential diagnosis of CV (sensitivity 56.7%, specificity 96.3%, sensitivity 29.4%, specificity 99.2%, respectively). Red blotches were significantly more common in CV lesions (P = 0.038). Red dots, comma vessels, and scales were more common in the non-CV group (P = 0.002, P = 0.002, P = 0.003, respectively). Interobserver agreement was very good for both pattern (???? = 0.869) and background color analysis (???? = 0.846) (P < 0.001). According to ML classifiers, the background color and lack of scales were the most significant dermoscopic aspects of CV. Conclusions: Dermoscopy may guide as a rapid and reliable technique in CV diagnosis. High accuracy rates obtained with ML methods may increase the success of dermoscopy.

Merkel cell carcinoma (MCC) is a rare, aggressive neuroendocrine skin carcinoma. The pathogenesis involves Merkel cell polyomavirus (MCPyV) and ultraviolet radiation exposure. Studies on MCC in Turkey are scarce, with essential data on local etiopathogenic and prognostic factors still lacking. We aimed to analyze the clinical and histopathologic features, biomarkers, and to evaluate these findings alongside Turkish literature to infer the etiopathogenesis, prognosis, and possible treatment options for the disease. We analyzed the clinicopathologic features of 7 MCC patients diagnosed at the Pathology Department of Pamukkale University between 2003 and 2024 in this retrospective study. Clinical data was retrieved from the hospital’s electronic records. Formalin-fixed, paraffin-embedded tumor specimens stained with hematoxylin-eosin were examined microscopically. MCPyV, Retinoblastoma 1 (RB1), p53, PRAME, PD-L1, and MMR proteins were evaluated immunohistochemically. Research on MCC from Turkey was sourced from Turkish databases (ULAKBIM, Turkiye Atif Dizini, DergiPark, Turk Medline) and international databases (Pubmed, Google Scholar, Scopus, Embase). The literature review identified original research, case reports, theses, and conference presentations. The patients in our series, all aged over 50 (mean age 76.1 ± 14.8), with a slight predominance of one gender (F: M = 1.33:1). During a mean follow-up of 16.1 months, 42.9% (3/7) had lymph node metastases, and 57.1% (4/7) showed distant metastases. PRAME was positive in 42.9% of the cases (3/7). The total number of MCC cases reported from Turkey was estimated at 227 ± 46, with MCPyV status available in a subset, showing a positivity rate of 70.3%. PD-L1 expression was observed in the tumor microenvironment in 55% of virus-positive MCC cases from Turkey. The 9% incidence of gluteal localization in Turkish MCC cases, considering its geographical significance, is noteworthy. Notably, all MCC cases from Turkey in which microsatellite instability status has been assessed were found to be microsatellite stable. PRAME should be investigated in larger series for its potential role in the shared oncogenic pathways of MCC.

Introduction: Endothelial damage is associated with acute and long-term Coronavirus disease 2019 (COVID-19) complications. Proximal nailfold capillaries are windows for monitoring important microvascular changes associated with endothelial dysfunction. Objective: We aimed to use dermoscopy to examine the proximal nailfold capillaries of COVID-19 patients and identify microvascular changes. Methods: A prospective study was designed to evaluate the dermoscopic features of proximal nail fold capillaries in mild to moderate COVID-19 patients and healthy controls between June 2022 and December 2023. The patients underwent their initial dermoscopic examination 2 weeks after the onset of symptoms, followed by a follow-up evaluation 10-14 months later. Results: The study included 46 patients with mild-to-moderate COVID-19 and 62 healthy controls. The presence of avascular areas (P<0.001), meandering capillaries (P=0.016), microhemorrhages (P=0.007), and enlarged capillaries (p=0.009) in the proximal nail fold is significantly higher in COVID-19 patients than in healthy controls The capillary architecture was disorganized (P=0.002) and density reduced (P<0.001) in COVID-19 patients compared to healthy controls. In the follow-up examination, microvascular changes were observed to regress. Conclusions: Proximal nailfold dermoscopy is an effective, low-cost, and easily accessible method that enables observing microvascular changes in COVID-19 patients.