Patch Test Research Articles

Patch Test Results with the Latin American Baseline Series in a Colombian Population. 2016-2021.

Background: Contact dermatitis (CD) is one of the most prevalent skin diseases. It is commonly divided into irritant contact dermatitis (ICD) and allergic contact dermatitis (ACD). Patch testing is a procedure used to support the diagnosis of ACD. This test should be interpreted along with the clinical history and morphology of the skin lesions to determine clinical relevance. Objective: To describe the sensitization patterns of patients undergoing patch testing with the Latin American baseline series. Methods: A single-center retrospective study was performed. For the study, patients older than 18 years with a clinical diagnosis of contact dermatitis, who underwent patch testing using the Latin American baseline series were considered. These tests took place at the Alma Mater Hospital of Antioquia between January 1, 2016, and December 31, 2021. Results: A total of 648 patients were included. Patch tests were positive in 63% of cases, with a mean age of 51.5 years. Around 36.6% had atopy-related diseases. The main occupation was housework (30.7%). The hands were the most affected area in the body (31%). The main allergens were nickel sulfate (34%), sodium tetrachloropalladate (24.2%), and thimerosal (8.0%). Fifteen allergens had a percentage below 1%. Hydrocortisone and budesonide did not yield positive results. Conclusion: Nickel sulfate was the most frequent allergen, and women were the most affected. The information gathered could be useful for adjusting the allergens that should be included in the regional baseline series, taking into account the frequency found.

Epidemiological case-control study on contact sensitisation in female foot care specialists with occupational contact dermatitis: Patch test data of the Information Network of Departments of Dermatology (IVDK), 2008 to 2022.

Mainly women work as foot care specialists (FCS). They are at risk to develop occupational dermatitis (OD). The objective of this study is to describe the contact sensitisation pattern of female FCS with OD. In a retrospective study, patch test and clinical data collected by the Network of Departments of Dermatology (IVDK) from 2008 to 2022 were analysed. Data of 116 female FCS with OD were compared with data of 13 930 female patients with OD working in other professions and 78 612 female patients without OD. Hand dermatitis (93.1%) was significantly more common and face dermatitis (0.9%) significantly less common in female FCS with OD compared to other female patients with or without OD. Frequent suspected allergen sources were disinfectants, gloves, leave-on and nail cosmetics. Occlusion and wetness were important co-factors. The most common diagnoses were irritant contact dermatitis (26.7%) and allergic contact dermatitis (21.6%). No sensitisation to any of the baseline series allergens was significantly more frequent in female FCS with OD than in the two control groups. However, sensitisations to allergens which FCS are abundantly exposed to, including fragrances, preservatives, rubber ingredients and disinfectants, were most common. FCS should be aware of the OD risk and prevention should be promoted.

Diagnosing contact dermatitis using machine learning: A review.

Machine learning (ML) offers an opportunity in contact dermatitis (CD) research, where with full clinical picture, may support diagnosis and patch test accuracy. This review aims to summarise the existing literature on how ML can be applied to CD in its entirety. Embase, Medline, IEEE Xplore, and ACM Digital Library were searched from inception to February 7, 2024, for primary literature reporting on ML models in CD. 7834 articles were identified in the search, with 110 moving to full-text review, and six articles included. Two used ML to identify key biomarkers to help distinguish between allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD), three used image data to distinguish between ACD and ICD, and one used clinical and demographical data to predict the risk of positive patch tests. All studies used supervision in their ML model training with a total of 49 704 patients across all data sets. There was sparse reporting of the accuracy of these models. Although the available research is still limited, there is evidence to suggest that ML has potential to support diagnostic outcomes in a clinical setting. Further research on the use of ML in clinical practice is recommended.

Anticipating the side effects of benznidazole: HLA-B*35 and patch test

IntroductionTreatment of Chagas disease frequently causes distress to patients due to a high incidence of adverse effects. Different preemptive tests have been researched to prevent these effects and to allow focus to be given to certain predisposed patients. Benznidazole is the most prescribed Chagas disease treatment in Spain.In this work, we analyzed the genetic markers HLA-B*35 allele group and HLA-B*35:05 allele specifically, as well as an allergy patch test, as benznidazole's most frequent adverse effects are cutaneous. MethodsHLA-B intermediate-resolution genotyping was performed followed by a high-resolution level analysis. Cutaneous allergies were tested using strips impregnated with a mixture of benznidazole and placed on the upper back of patients before starting treatment. ResultsIn our sample of more than 400 patients, there was almost no relationship between any kind of side effect and either of the HLA-B alleles studied. The patch testing was quickly discarded as a preemptive test due to its low sensitivity (16.7%). ConclusionIn conclusion, we were unable to replicate and corroborate genetic markers identified by other groups and there is currently no test that can anticipate the adverse effects of benznidazole, therefore, more investigation should be carried out in this field.

Comparative assessment of hot and warm mix asphalt to develop a sustainable pavement: Kg Ayer Merah Mersing case study

Abstract In this study, the construction and pavement properties of warm mix asphalt (WMA) in rural areas were examined in comparison with the conventional mixture of hot mix asphalt (HMA). Both WMA and HMA mixtures were constructed at Kg Ayer Merah, Mersing, Johor in accordance with Public Work Department specifications, regarding redesign of road pavements in rural areas. This study to evaluate the comparison performance of WMA and HMA mixtures at one month and four months after construction based on performance in mechanical (Rate of cooling, density, Marshall, resilient modulus and dynamic creep) and macrotexture performance (sand patch and pendulum test value) and environmental analysis (carbon emission). The findings showed that WMA mixtures showed similar and better performance over HMA mixtures after four months construction in mechanical performance. WMA also obtained a higher rate of cooling than HMA besides reducing carbon emissions during production and road construction indicating the mixture more convenient to cater for double handling in rural areas. This huge impact is in line with the sustainable development goals (SDGs), which aim to develop sustainable infrastructure and reduce global warming issues.

Diagnosis of Allergic Dermatoses in Skin of Color.

This review aims to deliver a comprehensive report of the most recent knowledge on diagnosing allergic dermatoses in skin of color (SOC) patients. Allergic dermatoses can affect populations of all backgrounds. However, racial/ethnic variations in epidemiology, clinical features, and associated allergens have been reported. Nuances in the approach to diagnosis, including the assessment of erythema and interpretation of patch tests, are important considerations when treating patients with SOC. In this review, we outline various manifestations of allergic dermatoses in SOC with a focus on important clinical presentations and diagnostic tools, aiming to support clinicians in accurate recognition of diseases, thereby opening avenues to improve outcomes across diverse skin types.

Identification of the pigments used in permanent makeup and their ability to elicit allergic contact dermatitis

Decorative tattoos are known to contain ingredients that may elicit allergic contact dermatitis; it is less well-known if permanent makeup pigments carry the same risk. Identify pigments used in permanent makeup inks sold in the United States and review cases of allergic contact dermatitis to these pigments. Using internet searches, permanent makeup inks sold in the United States were identified. Safety data sheets were used to catalog pigments used in permanent makeup. A subsequent literature search was performed to identify cases of allergic contact dermatitis to these pigments. A total of 974 permanent makeup inks were reviewed, and 79 unique pigments were identified. The average product contained 4 pigments. Twenty of the pigments were inorganic metals, including carbon, iron, chromium, manganese, and molybdenum. Fifty-nine pigments were organic, of which most were azo, quinacridone, or anthraquinone dyes. A literature search revealed that 10 of the 79 pigments were associated with allergic contact dermatitis. Permanent makeup primarily uses organic pigments, although some metallic pigments are still used. Physicians should also be aware that some of these pigments-both organic and inorganic-are known causes of allergic contact dermatitis. Of note, patch testing to these ingredients can be negative.

Severely compromised supply of patch test allergens in Europe hampers adequate diagnosis of occupational and non-occupational contact allergy. A European Society of Contact Dermatitis (ESCD), European Academy of Allergy and Clinical Immunology (EAACI), European Academy of Dermatology and Venereology (EADV) task forces 'Contact Dermatitis' and 'Occupational Skin Disease' position paper.

Patch testing is the only clinically applicable diagnostic method for Type IV allergy. The availability of Type IV patch test (PT) allergens in Europe, however, is currently scarce. This severely compromises adequate diagnostics of contact allergy, leading to serious consequences for the affected patients. Against this background, the European Society of Contact Dermatitis (ESCD) has created a task force (TF) (i) to explore the current availability of PT substances in different member states, (ii) to highlight some of the unique characteristics of Type IV vs. other allergens and (iii) to suggest ways forward to promote and ensure availability of high-quality patch testing substances for the diagnosis of Type IV allergies throughout Europe. The suggestions of the TF on how to improve the availability of PT allergens are supported by the ESCD, the European Academy of Allergy and Clinical Immunology, and the European Academy of Dermatology and Venereology and intend to provide potential means to resolve the present medical crisis.

IgE to wheat, prick test, and Patch test among children with celiac disease

Introduction and aimCeliac disease is one of the most common autoimmune disorders. This study aimed to evaluate the relationship between celiac disease and wheat sensitization.Subjects and methodsIn the current study, children aged < 18 years with confirmed celiac disease were included. Data were analyzed using SPSS.ResultsGastrointestinal problems were the most common indication for evaluation in terms of celiac disease. Prick and patch tests were positive in 43.4% and 34% respectively.ConclusionPrick test and patch test for wheat sensitization were positive in about 30–45% of the children for celiac disease.

WolfFuzz: A Dynamic, Adaptive, and Directed Greybox Fuzzer

As the directed greybox fuzzing (DGF) technique advances, it is being extensively utilized in various fields such as defect reproduction, patch testing, and vulnerability identification. Nevertheless, current DGFs waste a significant amount of resources due to their simplistic distance definitions and overly straightforward energy distribution for the seeds. To address these issues, a dynamic distance-weighting-based distance estimation strategy is proposed first, which facilitates strategies for seed distribution that take energy into consideration. Second, to overcome the limitations of current seed energy distribution strategies, the gray wolf optimizer (GWO) is improved by integrating four strategies, leading to the development of the improved gray wolf optimizer (IGWO). Lastly, an adaptive search algorithm is proposed, and the WolfFuzz prototype tool is implemented. In vulnerability recurrence scenarios, WolfFuzz is 3.2× faster on average compared with the baseline and reproduces 76.4% of existing bugs faster. WolfFuzz also discovers nine different types of bugs in seven real-world programs.

Acrylates and Methacrylates Sensitization in Patients with Orthopedic and Dental Prostheses: Asymptomatic Pre-Implant and Symptomatic Post-Implant Testing.

Acrylates and methacrylates are widely used in dental and orthopedic prostheses, false nails, adhesives, glues, and paints, and are strong sensitizers. The aim of our study was to assess the prevalence of acrylate sensitization in patients before the application of dental or orthopedic prostheses or after the application in case of potentially related contact dermatitis. Methods: The subjects were tested according to haptens reported in safety data sheets, including methyl methacrylate (MMA) 5%, methyl acrylate (MA) 1%, ethyl methacrylate (EMA) 2%, ethyl acrylate (EA) 1%, butylacrylate 0.1%, 2 hydroxyethyl methacrylate (HEMA) 5%, ethylene glycol dimethacrylate 2% (EGDMA), tetraethylene glycol dimethacrylate 2% (TEGDMA), and dimethyl amino ethyl methacrylate 0.2% (DAEMA). Multivariable logistic regression was used to study the factors associated with (meth)acrylate sensitization. Results: Six hundred sixty-five patients (75.4% of the total sample) without contact dermatitis before the placement of any dental or orthopedic prosthesis and 217 patients (24.6% of the total sample) with contact dermatitis potentially due to already placed prostheses were involved. In total, 37 cases of patch test positivity to at least 1 acrylate (4.2%) were found. In the pre-implant population, previous dermatitis and respiratory allergy were associated with increased sensitization to acrylates in multivariable regression analysis (odds ratio [OR] 2.38, 95% confidence interval [CI] 1.05-5.39; OR 2.96, 95% CI 1.32-6.64, respectively). The prevalence of sensitization was 3.5% for EGDMA, 2.7% for EA, 1.5% for 2-HEMA, 1.4% for both MA and MMA, 1.28% for DAEMA, and 0.8% for EMA. No statistically significant difference was found in the prevalence of sensitization between the pre- and post-implant groups. Discussion: Our study found a similar profile of sensitization in pre-implant and post-implant patients, suggesting the need to better study the specificity and sensitivity of patch tests to (meth)acrylate and to define relevance considering a detailed history of exposure.

Associations between tobacco smoking status and patch test results-A cross-sectional pilot study from the Information Network of Departments of Dermatology (IVDK).

Earlier studies suggested a potential association between tobacco smoking and nickel sensitization, but little is known about other contact allergens. To investigate the association of smoking status and contact sensitizations as well as subtypes of dermatitis, and to analyse the sensitization profiles of tobacco smokers. Within the Information Network of Departments of Dermatology (IVDK), we performed a cross-sectional multicentre pilot study comprising 1091 patch-tested patients from 9 departments, comparing 541 patients with a history of cigarette smoking (281 current and 260 former smokers) with 550 never-smokers. We could not confirm the previously reported association between nickel sensitization and tobacco smoking. Moreover, sensitizations to other allergens, including colophony, fragrance mix I, Myroxylon pereirae and formaldehyde, were not increased in cigarette smokers compared with never smokers. Hand dermatitis (50.6% vs. 33.6%) and occupational cause (36.2% vs. 22.5%) were significantly more frequent among cigarette smokers compared with never-smokers as shown by non-overlapping 95% confidence intervals. Although our study does not allow a firm conclusion on whether smoking status contributes to certain contact sensitizations, it confirms an association of smoking with hand dermatitis and occupational cause.

Influence of Surfactant on the Skin Permeation of Methylisothiazolinone and Methylchloroisothiazolinone.

Patch tests are often used in safety evaluations to identify the substance causing skin irritation, but the same substance can sometimes give positive or negative results depending on the test conditions. Here, we investigated differences in the skin penetration of two test compounds under different application conditions. We studied the effects of the anionic surfactant sodium dodecyl sulfate (SDS) and the nonionic surfactant polysorbate 80 (PS) on skin penetration of the preservatives methylisothiazolinone (MT) and methylchloroisothiazolinone (MCT), which are used in cosmetics such as shampoos. The skin permeation of MT was enhanced by SDS but was unchanged by PS. Skin impedance decreased in the presence of SDS whereas PS had the same effect as the control aqueous solution, suggesting that SDS reduction of the barrier function of skin affects the permeation of MT, a hydrophilic drug. Application of a mixture of MCT and MT in the presence of SDS did not affect the skin permeation of MCT whereas the permeation of MT was enhanced by SDS, indicating that the skin permeation of MCT is less affected by SDS than is MT. Thus, attention should be paid to the possible effect of co-solutes, especially hydrophilic drugs.

Contact sensitization and self-reported eczema in Swedish painters with occupational exposure to isothiazolinones.

Due to an increasing occupational usage of isothiazolinone (IT)-containing preservatives, and their potential to cause skin sensitization and allergic contact dermatitis, that is, chronic disease, there is a need for more knowledge on how highly exposed workers are affected. The overall objective was to explore dermatological symptoms of potentially long-lasting or chronic character in Swedish painters. Building painters from western and southern Sweden were initially invited to perform a questionnaire on occurrence of skin symptoms. Participants with affirmative responses, and the right inclusion criteria, were further invited to patch testing with four different ITs: benzisothiazolinone (BIT), methylisothiazolinone, methylchloroisothiazolinone and octylisothiazolinone. There was a tendency towards higher occurrence of positive patch test reactions among the painters compared with occupationally unexposed registry patients; however, not statistically significant differences. BIT was the substance most frequently causing positive test results in both groups. The occurrence of adult-onset eczema was higher in painters than in the control group of electricians, and just shy of statistical significance concerning any of several skin locations (face/legs/arms/hands). Building painters present with positive patch test reactions to common paint preservatives (ITs), and they report adult-onset eczema more often than do less occupationally exposed groups.

Symmetrical drug-related intertriginous and flexural exanthema (SDRIFE) after administration of corticosteroids: Case series and review of literature.

Cutaneous manifestations of drug-induced type IV reactions vary widely, with symmetrical drug-related intertriginous and flexural exanthema (SDRIFE) being a less common presentation. Corticosteroids (CS), primarily known for their anti-inflammatory effects, rarely induce hypersensitivity reactions. The aim of this case series is to report four cases of SDRIFE following systemic prednisolone therapy and to review existing CS classification proposals to better understand cross-reactivity of CS. Patients recruited at a German dermatology centre underwent allergologic evaluation including prick and patch testing with various CS. Positive cases underwent oral challenge testing with alternative agents. The classification systems of Coopman et al. and Baeck et al. were taken into account. Despite a paucity of literature, CS-induced type IV reactions do occur, including SDRIFE. Classification systems based on chemical structure provide insight into cross-reactivity patterns. Provocation tests with alternative CS highlight the complexity of managing CS hypersensitivity. SDRIFE may develop following systemic prednisolone therapy. Classification systems are helpful in understanding cross-reactivity and help in the selection of alternative preparations but are not always reliable. Individualised assessment is crucial for managing CS hypersensitivity, with consideration of alternative agents and emergency use of CS when necessary.

Synthesis of AgO/CuO/PVA/starch hydrogel by casting method and characterizations to safely overcome skin infections: A possible application in wound healing as a dressing

Wounds are frequently developing resistance to a conventional wound dressing. Therefore, bioactive and biodegradable hydrogel membranes that could serve as wound dressing could be a legitimate strategy for wound healing, Herein, a chemically cross-linking method was used to synthesize polyvinyl alcohol (PVA)/starch hydrogel, which was subsequently loaded, via the solution casting method, with Silver oxide/Copper oxide (AgO/CuO) nanocomposite (NC) tested at various concentrations (i.e., 0.1, 0.3, 0.5, and 0.7 g/L). The prepared hydrogels were physically characterized through standard techniques, including Dynamic Light Scattering (DLS), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), and Fourier Transform Infrared Radiation (FTIR). The influence of the different AgO/CuO NC concentrations was analyzed through tensile strength, swelling behavior, moisture retention capability (MRC), gel fraction, and water vapor transport (WVT) analyses. The relative toxicity (patch test) of hydrogel membranes was also evaluated on the human skin. The antibacterial potential was investigated against common skin pathogens (i.e., Salmonella typhimurium, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, and Candida albicans) through the disc diffusion method (DDM). SEM images depicted AgO/CuO/PVA/starch hydrogel membranes as shiny, smooth, and dense. XRD analysis revealed the purity and crystallinity of these hydrogels. FTIR data determined the functional chemical groups and confirmed the successful preparation of AgO/CuO/PVA/starch hydrogels. The increased concentrations of AgO/CuO NC in PVA/starch hydrogel membrane has boosted the tensile strength, swelling behavior, and MRC of the hydrogel membranes, whereas the WVT and gel fraction were decreased. Also, the AgO/CuO/PVA/starch hydrogel exerted enhanced antimicrobial activity against all the tested skin pathogens and no toxicity was observed when applied to the human skin. Taken together, the prepared AgO/CuO/PVA/starch hydrogel is a promising approach for wound dressing due to its desirable mechanical properties, safety, and its excellent barrier against skin pathogen penetration and infection.

Machine Learning in Allergic Contact Dermatitis: Identifying (Dis)similarities between Polysensitized and Monosensitized Patients

Background: Allergic contact dermatitis (ACD) is a delayed hypersensitivity reaction occurring in sensitized individuals due to exposure to allergens. Polysensitization, defined as positive reactions to multiple unrelated haptens, increases the risk of ACD development and affects patients’ quality of life. The aim of this study is to apply machine learning in order to analyze the association between ACD, polysensitization, individual susceptibility, and patients’ characteristics. Methods: Patch test results and demographics from 400 ACD patients (Study protocol Nr. 3765/2022), categorized as polysensitized or monosensitized, were analyzed. Classic statistical analysis and multiple correspondence analysis (MCA) were utilized to explore relationships among variables. Results: The findings revealed significant associations between patient characteristics and ACD patterns, with hand dermatitis showing the strongest correlation. MCA provided insights into the complex interplay of demographic and clinical factors influencing ACD prevalence. Conclusion: Overall, this study highlights the potential of machine learning in unveiling hidden patterns within dermatological data, paving the way for future advancements in the field.

O07 Lower doses of retinol facilitate cell proliferation and epidermal thickening in photoaged skin

Abstract Introduction and aims Chronic exposure to solar ultraviolet radiation leads to cutaneous hypertrophic photoageing which clinically manifests as wrinkles, skin laxity and hyperpigmentation. This photoaged phenotype is underscored by a remodelled cutaneous microenvironment including epidermal thinning and rete ridge flattening. We have previously shown that cosmeceutical formulations of 0.3% and 1% retinol can effectively induce epidermal thickening and keratinocyte proliferation. However, these concentrations require careful usage to limit potential irritancy issues, highlighting a need to explore the benefits of lower dose retinol for daily skincare. Therefore, we compare the efficacy of lower doses of retinol in facilitating epidermal thickness and proliferation in photoaged skin, as this currently remains unknown. Methods Using the in vivo Manchester Patch Test Assay, test substances (vehicle and retinol at concentrations of 0.025%, 0.05%, 0.1% and 1%) were applied under occlusion to extensor forearms of healthy but photoaged volunteers (three men, three women; age range 66–86 years) for 12 days. Resultant skin biopsies were processed for histological assessment of epidermal thickness and keratinocyte proliferation. Results Epidermal thickness was significantly increased with 0.025% (P &amp;lt; 0.05), 0.05%, 0.1% and 1% (all P &amp;lt; 0.01) retinol treatment, compared with baseline or vehicle. Immunofluorescence staining of the proliferation marker Ki67 identified elevated keratinocyte proliferation following retinol treatment (P &amp;lt; 0.05 for 0.025%, 0.05% and 1%) compared with baseline. Although Ki67 expression in the 0.1% retinol treatment was elevated, significance was not achieved compared with baseline. However, compared with the vehicle, all retinol concentrations significantly increased Ki67 expression (P &amp;lt; 0.05). Clinically, 50% of volunteers showed an erythemal irritancy response to 1% retinol only. Conclusions We established that lower doses of retinol are capable of inducing keratinocyte proliferation and epidermal thickening without irritancy issues. Therefore, long-term effective treatment of photoaged skin with low-dose retinol products may be the preferred choice for individuals where retinol sensitivity has previously been an issue.

Exploring antibiotic safety: A prospective observational study from a tertiary care public sector hospital

BackgroundAntibiotics are the most commonly used drugs to treat bacterial infections; however, these life-saving drugs can also cause adverse drug reactions. In several pharmacovigilance studies, adverse drug reactions are a cause of prolonged hospitalization. The development of hypersensitivity reactions even after a negative skin test and patch test makes antibiotic-associated adverse reactions unpredictable. Owing to the scarcity of data on antibiotic desensitization, these drugs are important for pharmacovigilance. Most of the previous studies conducted were retrospective and lacked data regarding the duration of adverse drug reactions. AimThis study aimed to examine adverse drug reactions associated with antibiotics and to provide knowledge on the duration of these reactions. MethodA prospective observational study was conducted on patients receiving antibiotics at a tertiary care hospital. The patients were followed until discharge, and causality and severity assessments were performed. Descriptive statistical analyses were performed to summarize the data. ResultsThe study results show the median duration of adverse drug reactions was two days, with an interquartile range of two to four days. Most (21,3%) of the reactions were caused by cephalosporins. The majority (44.7%) of the reactions were skin and subcutaneous tissue disorders. The majority (78.7%) of the reactions were moderately severe and were not responsible for prolonged hospital stay. ConclusionThe patients receiving antibiotics require close monitoring for early detection and management of adverse reactions to reduce the duration of hospital stay and the duration of adverse drug reactions.

Contact Dermatitis Due to Hair Care Products: A Comprehensive Review

Hair cosmetics are in fashion. Numerous products are commonly used in combination. Frequent allergens are present in hair cosmetics, which, with almost daily use, increase the risk of sensitization. Familiarity with the clinical distribution of the eczematous rash is necessary to seriously consider patch testing. Not all the products on the market are haptens. It is necessary to know how to patch your own products. When avoidance of the allergen is not possible, new treatments are evaluated to combat allergic contact dermatitis, mainly of the occupational type. In this manuscript, a complete and practical review of the main allergens and contact sources of hair cosmetic origin has been carried out.