Patch Test Procedure Research Articles

Allergic contact dermatitis caused by glucose sensors and insulin pumps: A full review: Part 2. Case reports and case series, clinical features, patch test procedures, differentiation from irritant dermatitis, management of allergic patients and (proposed) legislation.

During the past 8 years, a large number of reports have appeared on allergic contact dermatitis to glucose sensors and insulin pumps in paediatric and adult patients with type 1 diabetes mellitus. Isobornyl acrylate in one particular sensor sensitised many hundreds of (published) individuals, and many other allergens were discovered in a large number of sensors and pumps. Diagnostic procedures with patch tests proved very complicated, as manufacturers showed a serious lack of cooperation with dermatologists in providing information on the ingredients of their products and samples for patch testing. This two part article provides a full and detailed review of all aspects of the subject of allergic contact dermatitis to glucose sensors and insulin pumps. Part 1 provided a general introduction to sensors and pumps, a survey of the cutaneous adverse reactions that they have caused, a full account of the allergens in the diabetes devices and an overview of the glucose sensors and insulin pumps that have caused allergic contact dermatitis. This part 2 presents all published case reports and case series, clinical features of allergic contact dermatitis, patch test procedures, differentiation from irritant dermatitis, management of allergic patients and (proposed) legislation.

Allergic contact dermatitis caused by glucose sensors and insulin pumps: A full review: Part 1: Sensors and pumps, adverse cutaneous reactions, allergens, and diabetes devices causing allergic contact dermatitis.

During the past 8 years, a large number of reports have appeared on allergic contact dermatitis to glucose sensors and insulin pumps in paediatric and adult patients with type 1 diabetes mellitus. Isobornyl acrylate in one particular sensor sensitised many hundreds of (published) individuals, and many other allergens were discovered in a large number of sensors and pumps. Diagnostic procedures with patch tests proved very complicated, as manufacturers showed a serious lack of cooperation with dermatologists in providing information on the ingredients of their products and samples for patch testing. This two-part article provides a full and detailed review of all aspects of the subject of allergic contact dermatitis to glucose sensors and insulin pumps. Part 1 begins with a general introduction to sensors and pumps, followed by the cutaneous adverse reactions that they have caused and a full account of the allergens in the diabetes devices. In addition, an overview of the glucose sensors and insulin pumps that have caused allergic contact dermatitis is presented. Part 2 presents all published case reports and case series, clinical features of allergic contact dermatitis to sensors and pumps, patch test procedures, differentiation from irritant dermatitis, management of allergic patients and (proposed) legislation.

Texture Depth Measurement using a Micro-volume Measurement Technique for Gyratory Compactor Specimens

Introduction: Road safety plays a pivotal role in transportation infrastructure, as the quality of road surfaces is a crucial factor in ensuring safe driving conditions. One of the main indicators of road quality is the Mean texture depth (MTD), which greatly affects a vehicle's traction and skid resistance. Multiple methods are available for analyzing fabric depth, with the volumetric method, known as the sand patch test and standardized under ASTM E 965 – 96, being the traditional approach. Aim: This research aims to adapt a Sand Patch test procedure to evaluate surface texture depth on laboratory specimens with a 100 mm diameter and determine the required amount of sand, both in terms of weight and volume, to conduct this test effectively. Methods: To achieve this, the relationship between the amount of sand required and the sample size was determined. Two different types of asphalt mixtures were studied Stone Mastic Asphalt (SMA) and Asphalt Concrete (AC), with five gradation limits for each. Results: In the case of the AC10 mixture, the MTD ranged from 0.60 to 1.139 mm, while in SMA 20, the MTD ranged from 1.91 to 2.574 mm. These results are consistent with previous studies, confirming the reliability of the testing methodology, even when working with limited sample areas. Conclusion: In conclusion, the study highlights the potential simplicity and cost-effectiveness of using the Sand Patch micro-volume measurement method. When employed at the initial design stage, this method can provide valuable insights into surface texture, enhancing the design process and potentially further improving road safety.

2-Hydroxyethyl methacrylate (HEMA): A clinical review of contact allergy and allergic contact dermatitis. Part 2. Cross- and co-sensitization, other skin reactions to HEMA, position of HEMA among (meth)acrylates, sensitivity as screening agent, presence of HEMA in commercial products and practical information on patch test procedures.

This is the second part of a literature review of the clinical aspects of contact allergy to and allergic contact dermatitis from 2-hydroxyethyl methacrylate (HEMA). Topics include cross- and co-sensitization, atypical manifestations of contact allergy, frequency of positive patch tests to HEMA compared with other (meth)acrylates, sensitivity of HEMA as a screening agent, the presence of HEMA in commercial products, and practical information on patch testing procedures. Primary sensitization to methacrylates including HEMA may result in methacrylate and acrylate cross-sensitization. There is a strong cross-allergy between HEMA, ethylene glycol dimethacrylate (EGDMA), and hydroxypropyl methacrylate; many reactions to EGDMA are cross-reactions to primary HEMA sensitization. Rare atypical manifestations of HEMA-allergy include lichen planus, lymphomatoid papulosis, systemic contact dermatitis, leukoderma after positive patch tests, and systemic side effects such as nausea, diarrhoea, malaise, and palpitations. The occurrence of respiratory disease caused by methacrylates such as asthma is not infrequent. HEMA is the most frequently patch test-positive methacrylate. It is a good screening agent for allergy to other (meth)acrylates. Patch test sensitization to HEMA 2% pet. is extremely rare. There are (some) indications that HEMA is frequently used in dental products and nail cosmetics.

2-Hydroxyethyl methacrylate (HEMA): A clinical review of contact allergy and allergic contact dermatitis-Part 1. Introduction, epidemiology, case series and case reports.

2-Hydroxyethyl methacrylate (HEMA) has been increasingly recognised as a contact allergen and was added to the European baseline series in 2019. In this article (2 parts), the results of an extensive literature review of the clinical aspects of contact allergy/allergic contact dermatitis to HEMA are presented. In part 1, the epidemiology of HEMA contact allergy is discussed and detailed information on published case series and case reports presented. HEMA is an important cause of contact allergy/allergic contact dermatitis in North America and Europe with recent prevalences of >3% in the USA + Canada and 1.5%-3.7% in Europe. Currently, most cases are caused by nail cosmetics, both in consumers and professional nail stylists. In our literature review, we have found 24 studies presenting case series of patients with allergic contact dermatitis attributed to HEMA and 168 case reports. However, the presence of HEMA in the products causing ACD was established in only a minority. Part 2 will discuss cross- and co-sensitisation, and other skin reactions to HEMA, will assess whether HEMA is the most frequent (meth)acrylate allergen and how sensitive HEMA as a screening agent is, investigate the presence of HEMA in commercial products and provide practical information on patch testing procedures.

A Hands-on Approach to Contact Dermatitis and Patch Testing

Contact dermatitis (CD) is a common skin condition caused by contact with an exogenous agent that elicits an inflammatory response. Although history and physical examination can be helpful in distinguishing between irritant CD and allergic CD (ACD), the gold standard for diagnosing ACD is patch testing. Although the actual patch test (PT) procedure and application is relatively straightforward, the decisions involving which allergens to use, interpretation of results, determination of relevant allergens, and subsequent patient management require more skill and expertise. Often, the distribution of the presenting dermatitis can provide insight into the potential causative allergens and should be taken into account when selecting PT allergens. Commercially available PT panels and personal care products can be used for patch testing. Determining the clinical relevance of PT results is a critical component of the PT procedure. Patients must be educated on avoidance of relevant allergens and given guidance on alternative products available for use. Special populations, including children with ACD and occupational CD, and patients with biomedical devices have unique allergen considerations, and PT panels should be directed as such to address all potential allergens.

Optimal winding angle in laminated CFRP composite pipes subjected to patch loading: Analytical study and experimental validation

The research reported here sought to obtain the optimal winding angle (ϕ) in laminated carbon fiber reinforced polymer (CFRP) composite pipes under patch loading. To observe the sole effect of winding angle on the pipe's mechanical strength, the stacking sequence of the composite laminates ([ϕ/-ϕ/ϕ/-ϕ/ϕ]) was kept constant. An analytical investigation based on linear membrane shell theory was adapted to obtain the radial displacements (w) along the radial direction (z). A double Fourier series expansion was used during the analytical investigation. Two crucial factors were considered when selecting the optimal winding angle: (1) the minimum difference between the inward (compression) and outward (tensile) radial displacements, and (2) the minimum radial deflection at the circumference where patch loading is applied (θ = 00). The optimal winding angle, ϕ = 55°, was obtained using a classical trial and error technique. The analytical results for ϕ = 55° were then validated by an experimental investigation. Due to a lack of prior reported experimental investigations into radial deformation analysis of laminated composite pipes under patch loading, the manufacturing and test procedures have been discussed comprehensively in this paper. The pipe with optimal stacking sequence [55°/-55°/55°/-55°/55°] was first manufactured using the filament winding machine and then subjected to patch loading using the INSTRON machine. The experimental tests were conducted on three arbitrarily selected circumferential angles θ = (0°,48°,77°). The radial displacement at θ = 0° was measured using a tensile testing (INSTRON) machine. The radial displacements at θ = (48°,77°) were simultaneously measured using a laser displacement sensor (model: ANR 1150) and a dial indicator (model: 0.01–30 mm Mitutoyo), respectively. Ultimately, the radial displacements for a loading range of F = [0-800] (N) were obtained. There was good agreement between the analytical and experimental results, which offers a useful guideline for future design and manufacture of laminated composite pipes with elevated section.

Practical Advice to Correctly Perform Patch Test

Allergic contact dermatitis corresponds to an inflammatory reaction caused by contact with an external agent. It is a reaction mediated by a type IV hypersensitivity mechanism or delayed, and requires prior sensitization of the individual. Patch testing is the gold standard method for the diagnosis of allergic contact dermatitis. It is the in vivo proof of the effect caused by contact with the allergen, and evokes on a small scale the elicitation phase of a delayed hypersensitivity reaction. The patch test is not a complex procedure; however, its success depends on different factors that include an appropriate assessment of the patient considering the different sources of exposure to possible allergens, the correct technique of placement of the patches, and the necessary knowledge to properly interpret the results and determine their relevance. The objective of this review is to provide a series of general recommendations to adequately perform this test, and so the results are reliable and allow proper management of the patient. Although used for more than 120 years, the patch test procedure is performed with variability around the world. Although the procedure is broadly similar to the original method, it is not uncommon to observe differences in the results reported by the different observers. This may be influenced, among other factors, for differences in the methodology used by the physician who perform it. There are numerous potential points for error that the physician must keep in mind. Although during the last decades great efforts have been devoted to the optimization and standardization of the materials and the methodology, physicians’ knowledge and experience are fundamental for the reliability of the results and the benefits from this test.

Patch Test Series for Allergic Perineal Dermatitis in the Diapered Infant

Allergic perineal dermatitis (PD) due to diaper wipes, topical medicaments, or diapers has been reported. Although patch testing is the criterion standard for detection of allergic contact dermatitis in children, this is limited by body surface area, decreased tolerance of the patch testing procedure, and increased false-positive rates due to irritant reactions. Therefore, a targeted patch testing series is necessary to better screen diapered infants for possible allergic PD. We propose 2 patch test series (PD series 1 and 2) to screen infants with possible allergic PD. Allergens are chosen using existing sensitization data of common allergens in children, published case reports, and the collective experience of American Contact Dermatitis Society members through an electronic survey. PD series 1 includes 23 potential allergens found in wet wipes and topical diaper preparations. PD series 2 contains 10 potential allergens most commonly found in diapers. We believe that these judiciously chosen patch test series will increase the yield of detecting the causes of allergic PD while not exposing children to an unnecessarily large screening patch test panel.

Recommandations au patient avant les tests cutanés : évaluation de la fiche d’information du groupe dermato-allergologie de la Société française de dermatologie

Skin patch-tests in dermatology-allergology practice require good preparation. To this end, the dermatology-allergology group of the French Society of Dermatology introduced an information notice informing patients about patch testing procedures. The aim of this study was to evaluate the utility and understanding of the notice. The information notice was sent out to patients before testing. On the day of the test, a questionnaire was submitted to patients to evaluate their comprehension of the notice. Another questionnaire was submitted simultaneously to the dermatology-allergology practitioner to evaluate whether the patient had complied with the guidelines given in the information notice. Paired questionnaires were analyzed for this study. Eight dermatology-allergology hospital departments participated in the study and collected 921paired questionnaires over a period of 18months. Among the vast majority (96.2%) of patients who had read the information notice, most found it useful (98.8%), easy to read (97.4%), and appropriate (91.5%). Ten percent of patients had difficulty understanding. This study shows that the information notice was clear and explicit for the immense majority of patients. Thanks to the feedback of a number of patients, the information notice was further improved to enhance patient understanding.

International survey on skin patch test procedures, attitudes and interpretation

Background Skin patch test is the gold standard method in diagnosing contact allergy. Although used for more than 100 years, the patch test procedure is performed with variability around the world. A number of factors can influence the test results, namely the quality of reagents used, the timing of the application, the patch test series (allergens/haptens) that have been used for testing, the appropriate interpretation of the skin reactions or the evaluation of the patient’s benefit.Methods We performed an Internet –based survey with 38 questions covering the educational background of respondents, patch test methods and interpretation. The questionnaire was distributed among all representatives of national member societies of the World Allergy Organization (WAO), and the WAO Junior Members Group.Results One hundred sixty-nine completed surveys were received from 47 countries. The majority of participants had more than 5 years of clinical practice (61 %) and routinely carried out patch tests (70 %). Both allergists and dermatologists were responsible for carrying out the patch tests. We could observe the use of many different guidelines regardless the geographical distribution. The use of home-made preparations was indicated by 47 % of participants and 73 % of the respondents performed 2 or 3 readings. Most of the responders indicated having patients with adverse reactions, including erythroderma (12 %); however, only 30 % of members completed a consent form before conducting the patch test.Discussion The heterogeneity of patch test practices may be influenced by the level of awareness of clinical guidelines, different training backgrounds, accessibility to various types of devices, the patch test series (allergens/haptens) used for testing, type of clinical practice (public or private practice, clinical or research-based institution), infrastructure availability, financial/commercial implications and regulations among others.Conclusion There is a lack of a worldwide homogeneity of patch test procedures, and this raises concerns about the need for standardization and harmonization of this important diagnostic procedure.

Countering Staphylococcus Overgrowth During Patch Testing in Children with Moderate to Severe Atopic Dermatitis.

Patients with moderate to severe atopic dermatitis (AD) often have a concurrent diagnosis of contact dermatitis, but patch testing in these patients presents a unique set of challenges. Barrier impairment and Staphylococcus aureus colonization and infection, along with the sealed occlusion that takes place during the patch testing procedure, can create an optimal environment for bacterial overgrowth. To identify patients at risk for S. aureus overgrowth during patch testing and provide pre- and peripatch testing interventions to aid clinicians in obtaining the best possible patch test results in this complicated population. A retrospective review was performed of five patients with moderate to severe AD for which S. aureus overgrowth and superinfection complicated patch test evaluation. All five patients were able to complete the patch test procedure and all had relevant positive patch test reactions. Complications during patch testing included erythema, oozing, foul odor under the patches, and purulent material at the patch sites. One patient had a culture performed during patch testing that showed methicillin-sensitive S. aureus. Patch testing can play an important role in the examination and management of patients with refractory AD. Moderate to severe AD and concern regarding S. aureus overgrowth should not preclude patch testing.

Prevalence of fragrance contact allergy in the general population of five European countries: a cross-sectional study.

Contact allergy to fragrances is assessed mostly in clinical populations of patients. Studies in the general population are scarce and vary in their methodology across countries. To determine the prevalence of fragrance contact allergy in the European general population and to assess the clinical relevance of positive patch test reactions to different fragrances. In five European countries (Germany, Italy, the Netherlands, Portugal and Sweden) a random sample from the general population aged 18-74 years was drawn. In total, 12 377 subjects were interviewed in this cross-sectional study and a random sample (n = 3119) was patch tested using the TRUE Test and Finn Chamber techniques. Patch test procedures were harmonized by mandatory training before the study and monitoring during the study. The highest prevalence for contact allergy of 2·6% [95% confidence interval (CI) 2·1-3·2] was found for fragrance mix (FM) I in petrolatum, with a high content of atranol and chloratranol, followed by 1·9% (95% CI 1·5-2·4) for FM II in petrolatum. The conservatively estimated prevalence of fragrance contact allergy was 1·9% (95% CI 1·5-2·5). This is defined as the existence of a positive patch test to FM I or FM II; any of their individual materials; Myroxylon pereirae; sesquiterpene lactones or 3- and 4-hydroxyisohexyl 3-cyclohexene carboxaldehyde that show clinical relevance, defined conservatively as lifetime avoidance of scented products and an itchy skin rash lasting > 3 days in a lifetime. Using the reported lifetime prevalence of any contact dermatitis instead of the lifetime prevalence of any itchy skin rash, the prevalence is 0·8% (95% CI 0·5-1·2). The prevalence rates of contact allergy to fragrances in women are about twice those in men. This study helps to identify targets for prevention of fragrance allergy.

Patch testing custom isocyanate materials from the workplace.

Patch testing with standard trays of commercially available allergens is the current practice for investigating suspected cases of isocyanate-induced allergic contact dermatitis (ACD). In some facilities, these standard trays are further supplemented with custom preparations of isocyanate-containing materials. The aim was to determine whether added value exists in patch testing patients to custom isocyanate preparations in suspected cases of ACD. We performed a retrospective analysis of 11 patients referred to our specialty clinic between January 2003 and March 2011 for suspected patients of ACD who had custom testing with isocyanate materials from their workplace. In addition to standard trays of allergens, all patients were patch tested with custom isocyanate materials from their workplaces. Three (27%) of 11 patients showed an added value in testing to custom isocyanate allergens. Of these 3 patients, one had a reaction that reinforced positive reactions to the standard isocyanate tray, but the other 2 (18%) had no reactions to any of the commercially available allergens. Because of the high proportion of reactions (27%), we recommend the use of custom testing to workplace isocyanate products as a supplement to current standard patch testing procedures.

Patch Testing with the Swedish Baseline Series in Two Countries

Patch testing is a very effective mean to investigate causes of allergic contact dermatitis (ACD), but results obtained in different countries is usually hard to compare due to reading of patch tests. The aim of the study was to examine the prevalence of contact allergy to substances present in the Swedish baseline series and to compare results between the clinics in Vilnius and Sweden when the patch test procedure is similar in both countries. Consecutive patients with suspected ACD were tested with the Swedish baseline series at the university hospitals in Malmo, Sweden, and Vilnius, Lithuania in the years 2010–2012. Positive patch test reactions to at least one allergen was observed in 115 (53.7%) in Lithuania and in 237 (55.4%) in Sweden. The top 5 most frequent allergens (and respective prevalence rates) in Lithuania were as follows: nickel sulphate (25.7%), methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) (10.3%), cobalt chloride (7.5%), potassium dichromate (6.1%), formaldehyde (6.1%). The most prevalent positive patch tests reactions in Sweden were to nickel sulphate (18.9%), cobalt chloride (6.3%), M. pereirae resin (5.6%), MCI/MI (4.9%), Amerchol L 101 (4%). Statistically relevant differences were seen in sensitization to preservatives (3.7% in Lithuania and 1.8% in Sweden, p<0.001) and metals (13.1% in Lithuania and 9.3% in Sweden, p<0.03). In conclusion, this multicenter study provides some information on the prevalence of contact allergy to the most common contact allergens in two countries, although it is not possible to establish if the different prevalence was due to the difference in atopic background or allergen exposure. This should be further investigated.

The role of patch testing in non-immediate drug hypersensitivity reactions

Methods Herein we present case series of various non-immediate DHRs (occurring at any time as from 1 hour after the initial drug administration) amongst which drug-related intertriginous and flexural exanthema (Baboon syndrome), DRESS syndrome, fixed drug eruption and contact dermatitis. In all cases we performed patch testing with standardized and allergens prepared at our laboratory with the suspected drugs. The timing of patch test procedure was in median 6 weeks after the resolution of skin changes.

Contact Dermatitis: Therapeutics When Avoidance Fails

Contact dermatitis is one of the leading reasons to visit a dermatologist. There are two main types of contact dermatitis which result from exposure to chemicals: irritant contact dermatitis, which accounts for 80% of the cases, and allergic contact dermatitis, which accounts for 15%. Dermatologists must be cognizant of these diagnoses and consider appropriate and judicious use of the diagnostic patch test procedure. Once a clinically relevant allergen is diagnosed by patch testing, avoidance is the mainstay of therapy; however, medical management interventions may need to be employed in recalcitrant cases.

Patch Testing for Noncontact Dermatitis: The Atopy Patch Test for Food and Inhalants

The atopy patch test (APT) is defined as a patch test procedure to assess delayed type hypersensitivity reactions against those protein allergens known to elicit IgE-mediated type I reactions in atopic patients. This patch test procedure uses intact protein allergens instead of haptens in an optimized test setting and with a special reading key. It may be clinically useful especially for atopic dermatitis, as the currently available test procedures either target the wrong reaction type (type I and not type IV) or use the wrong allergens (haptens and not protein allergen). A positive APT reaction correlates with a positive lymphocyte transformation test and allergen-specific Th2 cells in the peripheral blood. As even small changes in the test procedure influence the sensitivity, specificity, and reproducibility of the APT, the European Task Force on Atopic Dermatitis (ETFAD) has developed a standardized APT technique: Intact protein allergens, purified in petrolatum, are applied in 12-mm-diameter Finn chambers mounted on Scanpor tape for 48 h to non-irritated, non-abraded, or tape-stripped skin of the upper back for 48 h; the evaluation of the test reaction is done after 48 and 72 h using the ETFAD reading key, assessing erythema as well as number and distribution pattern of the papules. The APT may reveal type IV sensitization in patients who are negative for the respective type I tests. Limited availability of the expensive test substances and limited reimbursement is among the factors restricting the routine use of the APT.

Time‐dependent modulation of serotonin and its receptors 1A and 2A expression in allergic contact dermatitis

Serotonin implication in allergic contact dermatitis was earlier suggested. To study the expression of serotonin (5-HT) and its receptors 1A and 2A during the kinetics of allergic contact dermatitis (ACD). Biopsies from 10 female nickel-allergic patients were obtained at 0, 6, 24, 48 and 72 h after nickel application using a patch testing procedure and then analysed by immunohistochemistry. Higher 5-HT epidermal immunoreactivity was seen at 0 and 6 h compared with 24, 48 and 72 h. The number of 5-HT labelled platelets was higher at 48 and 72 h compared with 0, 6 and 24 h. There was a decrease in the number of 5-HT1AR positive cells at 24, 48 and 72 h compared with 0 h. Furthermore, epidermal 5-HT1AR immunoreactivity was stronger at 48 and 72 h compared with 0 h. Total (dermis plus epidermis) number of 5-HT2AR positive cells was gradually increased in a time-dependent manner at 6, 24, 48 and 72 h compared with 0 h. Our results suggest the implication of 5-HT, 5-HT1AR and 5-HT2AR in the development of human ACD and the possibility to target those receptors at an early stage of this inflammatory condition.

The generalized finite point method

In this paper we propose a new mesh-less method based on a sub-domain collocation approach. By reducing the size of the sub-domains the method becomes similar to the well-known finite point method (FPM) and thus it can be regarded as the generalized form of finite point method (GFPM). However, unlike the FPM, the equilibrium equations are weakly satisfied on the sub-domains. It is shown that the accuracy of the results is dependent on the sizes of the sub-domains. To find an optimal size for a sub-domain we propose a patch test procedure in which a set of polynomials of higher order than those chosen for the approximations/interpolations are used as the exact solution and a suitable error norm is minimized through a size tuning procedure. In this paper we have employed the GFPM in elasto-static problems. We give the results of the size optimization in a series of tables for further use. Also the results of the integrations on a generic sub-domain are given as a series of library functions for those who want to use GFPM as a cheap and fast integral-based mesh-less method. The performance of GFPM has been demonstrated by solving several sample problems.