Patch Test Research Articles

Acute generalized exanthematous pustulosis induced by ceftriaxone with positive patch testing

Acute generalized exanthematous pustulosis induced by ceftriaxone with positive patch testing

Low-cost quantum mechanical descriptors for data efficient skin sensitization QSAR models

Quantitative Structure Activity Relationship modelling methodologies need to incorporate relevant mechanistic information to have high predictive performance and validity. Electrophilic reactivity is a common mechanistic feature of skin sensitization endpoints which could be concisely characterized with electronic descriptors which is key to enabling the modelling of small datasets in this domain. However, quantum mechanical methodologies have previously featured high computational costs which would exclude the use of large datasets. Consequently, we investigate the use of electronic descriptors calculated using the Hartree Fock with 3 corrections (Hf-3c) method, a low-cost ab initio methodology that has higher chemical accuracy than previous semiempirical methodologies for modelling in vitro skin sensitization assay outcomes. We also model the Ames assay as a surrogate for determining skin sensitization outcomes. The quantum chemical descriptors calculated using the Hf-3c method with conductor-like polarizable continuum model (CPCM) implicit solvation found improved QSAR model performance for the in vitro Ames (n = 6049, 0.770 AUC), KeratinoSens (n = 164, 0.763 AUC), and Direct Peptide Reactivity Assay (n = 122, 0.750 AUC) datasets, with their combination producing high predictive performance for unseen in vivo Local Lymph Node Assay (n = 86, 0.789 AUC) and Human Repeated Insult Patch Test (n = 86, 0.791 AUC) assay toxicant outcomes.

Comparison of Patch Test Results Before and After Mask Use in Patients With Facial Dermatoses

Comparison of Patch Test Results Before and After Mask Use in Patients With Facial Dermatoses

Analysis of patch test results in patients with suspected contact dermatitis in the Busan area

Analysis of patch test results in patients with suspected contact dermatitis in the Busan area

Results of patch testing to the European Baseline Series in adult patients in Turkey: a five-year experience at a tertiary reference center

Results of patch testing to the European Baseline Series in adult patients in Turkey: a five-year experience at a tertiary reference center

Allergic contact dermatitis to flowers: the importance of personalized patch testing

Allergic contact dermatitis to flowers: the importance of personalized patch testing

Europejska Seria Podstawowa, Polska Seria Podstawowa, Polski Standard… Dlaczego składy serii do testów płatkowych ulegają zmianom i jak to wpływa na praktykę kliniczną?

Europejska Seria Podstawowa, Polska Seria Podstawowa, Polski Standard… Dlaczego składy serii do testów płatkowych ulegają zmianom i jak to wpływa na praktykę kliniczną?

Anti UV, the Sun Protection Factor (SPF), and Irritation Test of Coastal Vegetation Ricinus communis

This study aims to test anti-UV activity, determine the SPF, and perform an irritation test on human skin from Ricinus communis leaf extract. The anti-UV and SPF values were determined using a UV-Vis Spectrophotometer. Furthermore, the irritation test was performed by observing the skin of human objects after cream with R. communis extract was applied. The results show that R. communis leaf extract has anti-UV-B activity, With SPF value categorized as high according to the US FDA at a concentration of 1000 ppm. Furthermore, observations from 20 participants from the patch test found no skin reactions such as edema, urticaria, irritation, and erythema on any of the objects. The Ricinus communis extract has the potential to develop as a natural sunscreen for human use.

Patch test in the diagnosis of food allergy

Food allergens are capable of producing adverse reactions through multiple mechanisms of an allergic or non-allergic nature, and through different routes of exposure; generally by ingestion or contact, as in protein contact dermatitis or contact urticaria, including inhalation. Food allergy reactions, in turn, can be mediated by immediate hypersensitivity mechanisms, delayed hypersensitivity or mixed immediate-delayed mechanisms. The reference diagnostic method in food allergy is the double-blind placebo-controlled food challenge test (DBPCFC), but skin and serological tests are important in the clinical context. The diagnosis of immediate food allergy depends on well-standardized allergological tests, such as the skin prick test (SPT) or specific IgE dosing, which are ideally tested by food challenge testing. However, the diagnosis of delayed mechanism food allergy and mixed allergies, which combine both immune mechanisms, is more complex. Delayed hypersensitivity reactions are evaluated with the epicutaneous patch test, or patch testing, for the diagnosis of contact dermatitis. The atopy patch test is initially used for the investigation of inflammatory reactions, which may be linked to food allergens in patients with atopic dermatitis. It was later applied in other diseases, whose pathogenesis is mainly mediated by a mechanism of delayed hypersensitivity to protein allergens: eosinophilic esophagitis, enterocolitis induced by food proteins, protein contact dermatitis, contact urticaria, among other disorders.

Measuring the Macrotexture of Pavement Surface Using an Image Processing Technique

The objective of this study was to propose an image processing-based index for measuring pavement macrotexture at the network level. This index enables macrotexture to be measured easily and inexpensively using images collected at traffic speed. The study involved collecting pavement surface images at a constant traffic speed on a test section specifically designed and constructed for this purpose, with three surface course mixes that are commonly used in India, namely, bituminous concrete, stone matrix asphalt, and gap-graded rubberized bituminous mix. Additionally, macrotexture data with regard to mean texture depth (MTD) from the sand patch test and mean profile depth (MPD) from laser sensor-based measurements were obtained at the locations where the images were captured. The surface macrotexture index (SMI), which was derived from wavelet transform-based image texture analysis, was compared with the MTD and MPD data. The results showed that the SMI is an accurate indicator of pavement surface macrotexture. In addition, the study showcased the application of an unsupervised machine learning algorithm to identify and replace outliers in the SMI data that resulted from isolated spots with dirt, pavement markings, and wet surfaces. The research also established relationships between the proposed SMI and MTD/MPD. These relationships are reliable and can be used to predict the commonly used pavement surface construction quality measure MTD and the network-level skid resistance indicator MPD.

Non-IgE-mediated Gastrointestinal Food Allergy in Children: Our Foods and Atopy Patch Test

Background: Food allergy (FA) is an increasing health problem in children. Previous studies have reported conflicting results about the diagnostic value of atopy patch test in food allergies. The aim of the present study was to investigate the accuracy of atopy patch test in identifying non-IgE-mediated gastrointestinal FA to pasteurized/homogenized cow›s milk, heated raw cow›s milk, white and yolk egg, soy, wheat, walnut, sesame, pistachio, almond, peanut, date and cumin which are popular food ingredients in southern Iran. Methods: This study was performed on children with gastrointestinal allergic problems who were not improved after at least 4 weeks of cow’s milk protein elimination. Atopy patch test (APT) was performed and the elimination diet was considered according to positive skin results and after resolving symptoms, introduction of each accused food was done sequentially. Results: Fifty tree children under 7 years old with mean age of 19.6 months underwent APT and the results were verified by open oral food challenge (OFC). Sensitivity in the range of 59%-95%, specificity of 80.7-92.8%, positive predictive values of 75-96.4% and negative predictive value of 23%-80.7% were calculated depending on the type of food. Compared to the heated raw cow’s milk, the pasteurized/homogenized cow’s milk reaction was significant. Conclusion: APT can be included in the diagnostic workup of non-IgE-mediated GI allergy because it is safe and has great accuracy. However, several aspects require further investigation especially to enable the standardization of the technique. We should be aware of the allergenicity of our foods due to processing and geographic region.

Solvent Induced Cumulative Insult Irritant Contact Dermatitis through Glove Permeation: A Case-Report on the Chronic Occupational Skin Lesion

A young female laboratory worker presented with chronic cumulative skin lesion over hands. The occupational exposure history supported the prolonged and frequent exposure to multiple solvents which are recognised as work irritants, improper work practice and wrong use of protective glove. The diagnosis of Irritant Contact Dermatitis (ICD) was supported by workplace dermatology risk factors, clinical features, negative skin patch test to rule out hypersensitivity reaction and fulfilment of all seven Mathias Criteria. The effective management of occupational contact dermatitis requires practices change and exposure control. The comprehensive Hand Care Programs must be individualised and incorporate several important elements namely the skin care screening and surveillance, early referral for Occupational Health assessment, effective education and training programs and provision of hand moisturising products. The support of return to work (RTW) among the affected workers is of paramount important in order to minimise the negative impacts on their quality of work as well as home life.

Contact allergy in atopic dermatitis: A prospective study on prevalence, incriminated allergens and clinical insights.

The relationship between atopic dermatitis (AD) and allergic contact dermatitis (ACD) is a matter of debate. The purpose of our study is to assess the frequency of ACD in patients with AD, the incriminated allergens and the potential risk factors. This is a prospective study, including cases of AD diagnosed based on Hanifin and Rajka's criteria. All patients were patch tested to the European baseline series and corticosteroid series. Ninety-three patients were included. Fifty-six patients (60.2%) had positive patch test results of which 71.4% were relevant. The most frequent allergens were: textile dye mix (24.7%), nickel (20.4%), cobalt (12.9%), isothiazolinone (8.6%), quanterium 15 (4.3%) and balsam of Peru (4.3%). Chromium, fragrance mix I, fragrance mix II and PTBP were positive in three cases (3.2%). Two cases of allergy to corticoids were identified. Facial involvement and duration of AD were significantly associated with contact sensitization (p = 0.04 and p = 0.005, respectively). Avoidance of relevant allergens resulted in a statistically significant decrease in SCORAD (p < 0.001). ACD remains an important co-morbidity of AD. We observed a high frequency of ACD to textile dyes, isothiazolinones and fragrances. Avoidance of relevant allergens has resulted in an improvement of patients' skin symptoms.

The contribution of metal allergy to the failure of metal alloy implants, with special reference to titanium: Current knowledge and controversies.

After almost three-quarters of a century during which contact dermatologists have often struggled to comprehend the relationship between metal allergy and failure of metal-alloy containing implant, it is possible to say that a relationship does exist, particularly for cobalt and chromium, but also for nickel. There is still debate as to whether allergy develops as a consequent of failure but thenceforth contributes to it, or whether sensitisation starts first and induces failure secondarily-opinion probably favours the first. Metal-on-polypropylene articulations were associated with few metal allergic problems but now are less favoured by orthopaedists due to plastic wear products causing osteolysis and pseudotumour formation through local inflammation. New metal alloys are regularly being introduced such that interested dermatologists need to stay on top of the situation. The jury is still out as to whether the recent favouring of titanium-containing alloys will confirm them to be more inert allergenically. Case reports do show some clinical reactions to titanium-containing implants and patch test series have inferred sometimes quite a high background rate of allergy, but interpretation must be tempered by the awareness that titanium salts on patch testing have a tendency to cause irritant reactions. Blood monitoring of metal ion values is now recommended in certain situations after joint replacement and increasing levels may be an indication that allergy with joint failure can develop, in which case patch testing is indicated, and suggested series are available. Predictive patch testing, whilst generally not recommended in the past, has been introduced into some protocols often by non-dermatologists, such that it is now needed for temporo-mandibular joint and Nuss bar insertion, and it can be anticipated that this may become more commonplace in the future. One of the major current deficits for patch testers is standardised guidance on which preparation or preparations to use for suspected titanium allergy. One suggestion is 0.5% titanium sulphate in petrolatum, though experience in at least one centre suggests the use of a battery of titanium salts might be desirable.

Testing and evaluation for skid resistance of steel slag asphalt wearing course based on surface texture characteristics

Steel slag can be utilized in asphalt wearing course as a substitute for aggregates. The surface texture of pavement is the critical factor affecting the friction behaviors and skid resistance. However, further research is needed to analyze the relationship between the surface texture and the skid-resistance performance of steel slag wearing course. In this study, four kinds of asphalt wearing course with different steel slag dosage (0%, 25%, 50% and 75% by volume) and two kinds of gradation (SMA-10, OGFC-10) were designed. Skid resistance of different specimen under different abrasion time was tested by sand patch test and British pendulum test. Laser scanning technology was used to capture and analyze the surface texture characteristics. The results showed that replacing basalt with steel slag could increase the skid resistance and anti-abrasion performance significantly and asphalt wearing course with 50% steel slag has the best skid resistance. The correlation coefficients between skid resistance and surface texture indexes of the specimens were higher than 0.9 before and after abrasion. Ra is more suitable than texture depth (TD) to represent the surface texture characteristics of the specimen and predict anti-skid properties of pavements.

Nickel Challenge In Vitro Affects CD38 and HLA-DR Expression in T Cell Subpopulations from the Blood of Patients with Nickel Allergy.

Nickel allergy is a major health problem and shows clinical manifestation of contact eczema. The response of specific lymphocyte subpopulations in sensitized patients after new challenge to nickel has until now not been studied in detail. To evaluate if nickel-based elicitation reaction could be objectively identified by multi-parametric flow cytometry, immunophenotyping of specific T cells was applied. White blood cells from 7 patients (4 positive in patch test, 3 negative) were challenged by nickel and in vitro short-term culture. Standardized antibody-dye combinations, specific for T helper(h)1, Th17 and cytotoxic T cell activation, were selected according to the recommendations of Stanford Human Immune Monitoring Center. In cytotoxic CD8+CCR7+CD45RA+ T cells from patients suffering from nickel allergy, CD38 and HLA-DR were elevated comparing to healthy donors. After challenge to nickel in vitro both markers decreased in CD8+CCR7+CD45RA+ T cells but found up-regulated in CD4+CCR7+CD45RA+CCR6-CXCR3+Th1 cells. Intracellular expression of T-bet and RORγt further indicated Th1 and Th17 cells. Finally, CD4+CD25+CCR4- T cells increased after challenge with nickel in PBMCs of patients with nickel allergy. Flow cytometry based quantification of T cell markers might be used as a specific and reliable method to detect chemical induced skin sensitization and confirm diagnostic patch testing in the clinics.

Contact allergies to dental materials in patients.

Concerns regarding contact allergies and intolerance reactions to dental materials are widespread among patients. Development of novel dental materials and less frequent amalgam use may alter sensitization profiles in patients with possible contact allergy. To analyse current sensitization patterns to dental materials in patients with suspected contact allergy. This retrospective, multicentre analysis from the Information Network of Departments of Dermatology (IVDK) selected participants from 169 834 people tested in 2005-2019 and registered with (i) an affected area of 'mouth' (and 'lips'/'perioral'), (ii) with the dental material in question belonging to one of three groups (dental filling materials, oral implants or dentures or equivalents) and (iii) with patch-testing done in parallel with the German baseline series, (dental) metal series and dental technician series. A total of 2730 of 169 834 tested patients met the inclusion criteria. The patients were predominantly women (81.2%) aged ≥ 40 years (92.8%). The sensitization rates with confirmed allergic contact stomatitis in women (n = 444) were highest for metals (nickel 28.6%, palladium 21.4%, amalgam 10.9%), (meth)acrylates [2-hydroxyethyl methacrylate (HEMA) 4.8%] and the substances propolis (6.8%) and 'balsam of Peru' (11.4%). The most relevant acrylates were HEMA, 2-hydroxypropyl methacrylate, methyl methacrylate, ethylene glycol dimethacrylate and pentaerythritol triacrylate. Few men were diagnosed with allergic contact stomatitis (n = 68); sensitization rates in men were highest for propolis (14.9%) and amalgam (13.6%). Allergic contact stomatitis to dental materials is rare. Patch testing should not only focus on metals such as nickel, palladium, amalgam and gold, but also (meth)acrylates and the natural substances propolis and 'balsam of Peru'.

Efficient implementation on accuracy improvement of the two-dimensional node-to-segment contact approach for explicit dynamic analysis

The penalty-method-based node-to-segment (NTS) approach is widely employed in the explicit dynamic analysis owing to its computational efficiency and implementation simplicity. However, the classical approach does not pass the contact patch test and results in severe inaccuracies. This study attempts the accuracy enhancement of an explicit dynamic contact analysis with minimum efficiency loss using the NTS algorithm with the modified area regularization technique (NTS-mAR). The computational procedure is compared to an allied modified penalty-method-based NTS approach, i.e., the virtual node-to-segment algorithm passing the patch test (VTS-PPT). Then, an extension to an explicit dynamic analysis framework is attempted, wherein the speed of the contact force calculation significantly influences the overall computational efficiency. The cost of the remaining computation was minimized by employing a lumped mass matrix and a one-point integration rule for the internal force. Elastoplasticity was considered to extend its application. The accuracy improvement compared to the classical one-pass NTS approach was similar for the modified approaches. The VTS-PPT approach requires more than twice the cost of contact force estimation compared with the classical one-pass NTS approach. In contrast, NTS-mAR approach induces a cost increase from 6 to 36% that of classical one-pass NTS approaches. For the given examples, the NTS-mAR approach is beneficial when an improvement in accuracy is desired with minimum efficiency loss.

Gender differences in allergic contact dermatitis to common allergens.

Gender-based differences in skin structure, physiology, and allergen exposure can influence contact dermatitis development. This study investigated the differences and trends in contact sensitizers, focusing on the top 10 allergens and personal care product (PCP) contact allergies from a gender perspective. We conducted a retrospective chart review of 5998 patients undergoing patch testing at an occupational and contact dermatitis clinic in a Thai, university-based, tertiary referral hospital from January 2001 to December 2021. Patients' characteristics and patch test results were collected. Females had a higher positive patch test rate than males (71.8% vs. 65%, p < 0.001). However, males showed a greater prevalence of occupationally related allergic contact dermatitis (15.9%). Multivariate analysis revealed associations between being female and allergies to colophonium (aOR 1.46, 95% CI 1.07-1.99, p = 0.019), formaldehyde (aOR 1.97, 95% CI 1.17-13.31, p = 0.010), fragrance mix I (aOR 1.66, 95% CI 1.34-2.07, p < 0.001), MCI/MI (aOR 2.55, 95% CI 1.90-3.44, p < 0.001), neomycin (aOR 4.15, 95% CI 2.54-6.80, p < 0.001), and nickel (aOR 2.62, 95% CI 2.17-3.15, p < 0.001). Conversely, being male correlated with allergies to carba mix (aOR 0.51, 95% CI 0.41-0.64, p < 0.001), epoxy resin (aOR 0.26, 95% CI 0.14-0.47, p < 0.001), n-isopropyl-n-phenyl-4-phenylenediamine (aOR 0.41, 95% CI 0.20-0.83, p = 0.014), paraben mix (aOR 0.42, 95% CI 0.32-0.56, p < 0.001), and potassium dichromate (aOR 0.70, 95% CI 0.58-0.84, p < 0.001). Positive reactions to PCPs stood at 13% overall (males 17.1%, females 12.2%, p < 0.001). Gender plays a pivotal role in contact dermatitis. This work emphasises the importance of considering gender-specific factors when diagnosing and managing contact allergies.

Novel roles of bovine milk-derived exosomes in skin antiaging.

Exosomes are small vesicles released from cells and are found in various mammalian biological fluids, such as bovine milk, which has been employed in skincare for many years, apart from its dairy applications. In addition, exosomes have been recognized as vehicles for intercellular communication. In this study, we aimed to investigate the novel effects of bovine milk-derived exosomes (MK-Exo) on antiaging in human skin. Initially, MK-Exo were co-cultured with keratinocytes and fibroblasts; subsequent analysis involved qPCR and western blotting to assess induced gene expression. Subsequently, MK-Exo were topically applied to the facial skin of 31 female volunteers twice daily for 28 days. The functions were evaluated after conducting safety assessments invivo. Purified MK-Exo demonstrated the ability to be taken up directly by keratinocytes and fibroblasts invitro, resulting in the upregulation of natural factors associated with skin moisturization, including filaggrin (FLG), aquaporin 3 (AQP3), and CD44 in keratinocytes, as well as hyaluronidase (HAS2) in fibroblasts. Concurrently, MK-Exo promoted fibroblast cell migration and restored the expression of type I and III collagen (Col I and Col III) following exposure to ultraviolet radiation. Furthermore, phototoxicity, photoallergy, repeated skin irritation, skin allergy, and patch tests confirmed the safety of MK-Exo for skin application. Finally, we elucidated the roles of MK-Exo in preserving moisture and reducing wrinkles in humans. Our findings unveil the novel contributions of MK-Exo to human skin aging, presenting a new avenue in the field of skincare.