Background: The Human Cell Differentiation Molecules (HCDM) organizes Human Leukocyte Differentiation Antigen (HLDA) workshops to test and name clusters of antibodies that react with a specific antigen. These cluster of differentiation (CD) markers have provided the scientific community with validated antibody clones, consistent naming of targets and reproducible identification of leukocyte subsets. Still, quantitative CD marker expression profiles and benchmarking of reagents at the single-cell level are currently lacking.Objective: To develop a flow cytometric procedure for quantitative expression profiling of surface antigens on blood leukocyte subsets that is standardized across multiple research laboratories.Methods: A high content framework to evaluate the titration and reactivity of Phycoerythrin (PE)-conjugated monoclonal antibodies (mAbs) was created. Two flow cytometry panels were designed: an innate cell tube for granulocytes, dendritic cells, monocytes, NK cells and innate lymphoid cells (12-color) and an adaptive lymphocyte tube for naive and memory B and T cells, including TCRγδ⁺, regulatory-T and follicular helper T cells (11-color). The potential of these 2 panels was demonstratedviaexpression profiling of selected CD markers detected by PE-conjugated antibodies and evaluated using 561 nm excitation.Results: Using automated data annotation and dried backbone reagents, we reached a robust workflow amenable to processing hundreds of measurements in each experiment in a 96-well plate format. The immunophenotyping panels enabled discrimination of 27 leukocyte subsets and quantitative detection of the expression of PE-conjugated CD markers of interest that could quantify protein expression above 400 units of antibody binding capacity. Expression profiling of 4 selected CD markers (CD11b, CD31, CD38, CD40) showed high reproducibility across centers, as well as the capacity to benchmark unique clones directed toward the same CD3 antigen.Conclusion: We optimized a procedure for quantitative expression profiling of surface antigens on blood leukocyte subsets. The workflow, bioinformatics pipeline and optimized flow panels enable the following: 1) mapping the expression patterns of HLDA-approved mAb clones to CD markers; 2) benchmarking new antibody clones to established CD markers; 3) defining new clusters of differentiation in future HLDA workshops.

Granulomatous pigmented purpuric dermatosis clinically manifests as hyperpigmented maculae and petechiae, predominantly on the lower extremities. Histopathologically, it is characterized by a lymphocytic infiltrate in the upper dermis, extravasated erythrocytes, and hemosiderin deposits. There is an infrequent variant called granulomatous pigmented purpuric dermatosis, which histologically is characterized by the presence of non-necrotizing granulomas associated with the classic findings of other pigmented purpuric dermatoses. It more frequently affects middle-aged women of Asian origin, and predominantly on the lower extremities. The authors present the case of a female patient with granulomatous pigmented purpuric dermatosis on the lower extremities with blaschkoid distribution.

Background: Psoriasis is a chronic inflammatory skin disease associated with several important medical comorbidities. There are scant data available on the comorbidities of patients with psoriasis in South America.Aim: To examine the comorbidity profile of adult patients with psoriasis in Chile and its association with severity of psoriasis.Methods: This was a multicentre, cross-sectional study involving 16 hospitals and clinics in Chile, which used a 48-item questionnaire to study clinician- and patient-reported outcomes and comorbidities. Inferential analyses were performed by psoriasis severity, using Fisher exact test, Student t-test and multivariable logistic regression.Results: In total, 598 adult patients with psoriasis were included (51.1% male; mean age 49.2 ± 15.1 years); 48.5% mild and 51.4% moderate to severe; Psoriasis Area and Severity Index 11.6 ± 11.5; body surface area 14.7 ± 18.2%. Plaque psoriasis was the most common phenotype (90.2%), followed by guttate (13.4%). Psoriatic arthritis occurred in 27.3% of patients. Comorbidities were reported in 60.2% of all patients with psoriasis. Frequent concomitant diseases were obesity (25.3%), hypertension (24.3%), Type 2 diabetes mellitus (T2DM) (18.7%), dyslipidaemia (17.4%), metabolic syndrome (16.7%) and depression (14.4%). After adjustment, significant associations were found between moderate to severe psoriasis and obesity, T2DM and nonalcoholic fatty liver disease (NAFLD) compared with mild psoriasis.Conclusions: We report a large study of comorbidities, including depression, dyslipidaemia, T2DM and NAFLD, in people with psoriasis in Chile. The prevalence of comorbidities with psoriasis in Chile appears similar to that found in Western countries, and emphasizes the importance of assessing patients with psoriasis for risk factors for and presence of, comorbid disease in a multidisciplinary setting.

Emerging epidemiological evidence links atopic dermatitis (AD) and periodontitis, although the mechanisms remain unclear. Th2-derived cytokines are key in the development of both diseases, and different gingival crevicular fluid (GCF) profiles among healthy and diseased subjects have been previously reported. This case–control study examined the GCF levels of interleukins (IL)-13, IL-31, and thymic stromal lymphopoietin (TSLP) in 29 subjects with moderate-to-severe AD and 33 controls. All subjects underwent comprehensive clinical and oral evaluations, followed by GCF collection. GCF levels of IL-13, IL-31, and TSLP were assessed using a multiplex-bead immunoassay. Demographic and periodontal parameters were similar among groups (p > 0.05). The GCF levels of IL-31 and TSLP were higher in AD subjects compared to controls (p < 0.05), whereas no significant differences in the GCF levels of IL-13 were noticed (p = 0.377). Moderate-to-severe AD was positively associated with the GCF levels of IL-31 and TSLP, whereas severe periodontitis was negatively associated with IL-31 (p < 0.05). The GCF levels of IL-13 showed no significant associations with either condition (p = 0.689). There was no significant interaction between AD and periodontitis for IL-31 (p < 0.869). These results suggest that AD and periodontitis independently influence the GCF levels of IL-31 in opposing ways, whereas AD alone influences the levels of TSLP.

Erythrodermic psoriasis is a rare but severe type of psoriasis that may be triggered by human immunodeficiency virus infection. We describe the case of a 65-year-old male patient with chronic psoriasis who presents an exacerbation of his condition over a period of two weeks. Because of the severity of his case and subsequent need for systemic therapy, human immunodeficiency virus enzyme immunoassay was performed and tested positive. He thus began antiretroviral therapy combined with acitretin, showing good clinical response after 8 weeks of treatment. There is little evidence regarding the management of erythrodermic psoriasis associated with HIV infection, so antiretroviral therapy and systemic retinoid remain as the first-line treatment.

Psoriasis has been associated with various autoimmune diseases, however, its relation to bullous diseases is infrequent. Of these, bullous pemphigoid appears as the main associated entity, even though both conditions differ considerably in demographic and clinical aspects. We report the case of a 42-year-old female patient, with long-standing psoriasis who consulted due to the exacerbation of psoriatic plaques associated with generalized bullous lesions on the skin and oral mucosa, with one-week duration. With clinical signs and histopathological findings compatible with bullous pemphigoid associated with psoriasis, we decided to treat her with methotrexate 10mg a week. The patient had an excellent response after two months of treatment.