North American Contact Dermatitis Group Patch Test Results: 2019-2020

Prevalence of Contact Allergy to Neomycin in Dermatitis Patients: A Systematic Review and Meta-Analysis

Neomycin, an aminoglycoside antibiotic frequently employed in topical formulations, is a recognised allergen that is part of many baseline series and can cause contact allergy (CA) in both adults and children. It is an allergen of interest as it has a widespread use in over-the-counter and prescription products globally, but geographical variations may exist. This study aimed to establish prevalence estimates of CA to neomycin in dermatitis patients and to investigate potential geographical variations. Three databases (PubMed, Embase, and Web of Science) were screened, revealing 70 included studies comprising 456 372 adults and 17 720 children who underwent patch testing. The pooled prevalence of CA to neomycin was found to be 3.2% (95% confidence interval [CI]: 2.6%-3.8%) in adults and 4.3% (95% CI: 2.65%-6.3%) in children. The highest prevalences were observed in North America (adults: 6.4%; children: 8.1%) and South Asia (adults: 4.9%), while Europe showed lower rates (adults: 2.5%; children: 0.8%). Studies after the year 2000 indicated a prevalence of 2.1% in adults and 5.1% in children across geographical regions. These findings highlight a public health concern, particularly in regions with high prevalence rates. The study underscores the need for more restrictive use of neomycin to reduce the incidence of neomycin-induced CA.

Allergic Contact Dermatitis in Skin of Color: A Retrospective Study from a Comprehensive Patch Testing Center

Background: There are few studies reporting patch test results in skin of color patients, especially for Hispanic, Asian, and Indigenous populations. Objective: To characterize patch testing results in patients with skin of color at our center. Methods: A retrospective study of patients demonstrating at least 1 allergenic reaction in comprehensive patch testing (+, ++, +++, or +/-) with final interpretation as allergic by a board-certified dermatologist specializing in contact dermatitis. Results were stratified by self-reported race and the most common reactions for each group were characterized and compared to those of White patients. Results: A total of 1389 patients were identified; 270 (19.4%) having skin of color (1119 White, 102 Asian, 115 Black or African American, 44 Hispanic, 9 Indigenous). Most common reactions among Asian patients were nickel, methylisothiazolinone (MI), and hydroperoxides of linalool. In Black patients, MI, nickel, and p-phenylenediamine were most common. In Hispanic patients, MI, nickel, and formaldehyde were most common. The positivity of acrylates (P < 0.001) and propylene glycol (P < 0.05) in Asians as well as dyes and rubber accelerators in Black patients (P < 0.05) was significantly higher than in White patients. Conclusions: Nickel and MI are common allergens in all groups, with certain allergens being overly represented in some groups. Differing cultural practices may result in these variations, emphasizing the need to capture patch testing trends in these populations.

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.

Comparison of patch testing Brazilian (Green) propolis and Chinese (poplar-type) propolis: Clinical epidemiological study using data from the Information Network of Departments of Dermatology (IVDK)

BACKGROUND

Propolis types differ regarding their chemical composition.

OBJECTIVES

To compare patch test results based on Brazilian (Green) propolis with data based on Chinese (poplar-type) propolis, and to evaluate the specifications of raw materials used for the PT preparations.

METHODS

In the Information Network of Departments of Dermatology (IVDK), 1290 consecutive patients were patch tested with Brazilian (Green) propolis (NH400, SmartPractice Europe). Patch test reactivity was compared with results obtained with Chinese (poplar-type) propolis (NA71, SmartPractice Europe) by calculating frequencies and corresponding 95% confidence intervals. Data on the specifications of raw materials used for NH400 and NA71 were obtained from the manufacturer.

RESULTS

Positive reactions to NH400 were found in 303 (23.5%) patients with unclear clinical relevance in most cases. Patients reacting to NH400 were less often sensitised to fragrances and colophony, but more often to nickel sulphate and cobalt chloride than patients reacting to NA71. The NH400 batch used contained high levels of aerobic bacteria, and was not purified by ethanolic extraction.

CONCLUSIONS

Pattern of concomitant reactivity along with raw material properties suggests that the high frequency of positive reactions to NH400 may primarily result from bacterial contamination or impurities in the PT preparation rather than from propolis constituents.

Interference of the positioning of nickel, chromium and cobalt in the results of patch tests

BACKGROUND

The positioning of substances, which are co-sensitizers and/or with a tendency to cross-react, is not considered in the technique when applying patch tests (PT).

OBJECTIVE

To investigate the interference of the positioning of nickel (Ni), chromium (Cr) and cobalt (Co) in patch tests (PT) results, when applied close or distant from each other.

METHODS

PT were performed in patients suspected of allergic contact dermatitis (ACD), using the standard battery (SB), with substances showing a tendency towards cross-react and co-sensitizers applied far apart, and an additional battery (AB) with the metals placed close to each other. For tabulation purposes, only the 96-h reading was considered.

RESULTS

Of the 86 tested patients, 33 (38%) had negative testing for metals and 53 (62%) had one or more positive (+) tests for Ni, Cr and/or Co. Concordant results in both tests (SB/ AB) occurred in 18/53 (34%) and 35/53 (66%) had discordant results. Regarding the SB, of the 159 tests with metals (53 patients, three metals), 57 tests were (+) and 102 (-). In the AB, 87 tests were (+) and 72 (-), a statistically significant difference (p < 0.05). Of the 57 (+) tests in the SB, 35 were for Ni, 18 for Co and four for Cr. In AB the number of (+) tests was 87, with 45 (+) tests for Ni, 35 for Co and seven for Cr. The difference in the number of positive tests between the two batteries was statistically significant for Co and Ni.

STUDY LIMITATIONS

The number of cases.

CONCLUSION

The results showed that the positioning of the metals interferes with the PT results and should be considered as part of the PT application technique.

Insights into hair dye use and self-reported adverse skin reactions in the Dutch general population: A cross-sectional questionnaire-based study

BACKGROUND

Hair dyes are widely used in daily life. However, data on self-reported adverse skin reactions are scarce.

OBJECTIVES

To estimate the proportion of lifetime hair dye use and self-reported adverse skin reactions in the Dutch general population, and to investigate the association between (adverse skin reactions to) hair dye use and contact allergy-related factors.

METHODS

This cross-sectional study collected questionnaire-derived data from the Lifelines cohort. Logistic regression analyses were conducted between (adverse skin reactions to) hair dye use and black henna tattoo use, reactions to henna tattoos, patch testing, hand eczema and an occupation as hairdresser or beautician.

RESULTS

The proportion of hair dye use was 63.1% of 70 987 participants, of which 6.8% experienced adverse skin reactions, mostly mild (77.7%). Hair dye users and those with skin reactions were both positively associated (p < 0.05) with female sex, middle-age, (positive) patch test results and hairdresser or beautician occupations. Hair dye users were more likely to have had henna tattoos, and those with reactions to hair dye were more likely to have had reactions to henna tattoos.

CONCLUSIONS

Hair dye use is prevalent among the Dutch general population and frequently causes adverse skin reactions, especially in females who had black henna tattoos.

A Retrospective Study of Pediatric Allergic Contact Dermatitis from 2017-2022

OBJECTIVES

Allergic contact dermatitis occurs frequently in children. The proportion of children of color in the US is increasing, and racial and ethnic minority representation is important in pediatric allergic contact dermatitis research. The objectives of our study were to identify differences in age, sex, race and ethnicity among pediatric patch tests obtained from 2017 to 2022.

METHODS

A total of 792 pediatric patients were evaluated, and patch test differences were analyzed among age, sex, race and ethnicity groups.

RESULTS

Children in the age group 0-5 years had the highest number of positive reactions, and propolis was the most frequent allergen among females and in children in the age groups 6-11 years and 12-18 years. Carmine was the most frequent allergen among males and among children in the age group 1-5 years. Risk of sensitivity to multiple allergens varied with race and ethnicity.

CONCLUSIONS

The risk of patch test positivity to multiple allergens varied within the demographic groups evaluated. The etiology of these differences is likely multi-factorial and includes differences in exposure patterns and disparities in access.

Contact Dermatitis in the United States: A Population-Based Study on Patient Visit Characteristics and Treatment Prescription Patterns

Background: Contact dermatitis (CD) affects ∼15% of the general population over a lifetime. However, there is a lack of epidemiological studies on treatment patterns for CD. Objective: We aim to analyze the patient characteristics and prescribing patterns among dermatologists and general practitioners (GPs) (internal medicine [IM] and family medicine [FM]) for CD in the United States. Methods: We conducted a population-based study using the National Ambulatory Medical Care Survey. Results: We identified 178,017,680 weighted patient visits for CD from 2001 to 2016. Dermatologists saw more white and non-Hispanic patients than GPs. GPs were less likely to prescribe ultrahigh potency topical corticosteroids (FM OR 0.27; P < 0.001, IM OR 0.41; P < 0.001) and more likely to prescribe oral antihistamines (FM OR 3.71; P < 0.001, IM OR 3.56; P < 0.001), oral corticosteroids (FM OR 5.35; P < 0.001, IM OR 6.87; P < 0.001), and injectable corticosteroids (FM OR 3.42; P = 0.006, IM OR 5.68; P < 0.001) than dermatologists. Conclusions: Across CD visits, GPs were less likely than dermatologists to prescribe ultrahigh potency topical corticosteroids and more likely than dermatologists to prescribe oral antihistamines and systemic corticosteroid therapy.

Toluene-2,5-Diamine Sulfate: Allergen of the Year 2025

Toluene-2,5-diamine sulfate (PTDS), also known as toluene diamine sulfate or 2,5-diaminotoluene sulfate, is an aromatic amine that can be used as a paraphenylenediamine (PPD) hair dye alternative. Patients may develop contact allergy to PTDS, and it is often omitted from standard patch test screening series, possibly leading to underdiagnosis. The American Contact Dermatitis Society named PTDS the Allergen of the Year for 2025, aiming to raise awareness of its dual role as both an allergen and an alternative for some PPD-allergic individuals.

Prevalence of contact allergy to gold in dermatitis patients from 2010 to 2024: A systematic review and meta-analysis

Gold contact allergy is diagnosed by patch testing using gold chloride or gold sodium thiosulfate. These tests often show high positivity rates, but a direct correlation with dermatitis from everyday gold exposure is rare. The aim of this study was to investigate and estimate the current prevalence of gold contact allergy in dermatitis patients. We performed a systematic literature search in PubMed, Embase and Web of Science for studies reporting the prevalence of gold contact allergy in dermatitis patients and published between January 2010 and May 2024. Data extraction and quality assessment were performed, and pooled proportions were calculated using random effects models. Sixteen studies with 14 887 dermatitis patients were included. The pooled prevalence of gold contact allergy was 14.1% (95% confidence intervals: 9.5%-19.4%) with significant heterogeneity (I2 = 98.3%). High positivity rates with limited clinical relevance highlight the need for cautious interpretation. Even within the same country, studies find different prevalence rates. Standardized testing protocols and further research are needed to better understand and manage this allergy.

Photopatch testing: Clinical characteristics, test results, and final diagnoses from the North American Contact Dermatitis Group, 2009-2020

BACKGROUND

Photoallergic contact dermatitis (PACD) is a delayed hypersensitivity reaction to allergens only in the presence of ultraviolet radiation in sunlight. Photopatch testing (PhotoPT) is necessary to confirm the diagnosis of PACD. There are few published studies of PhotoPT in North America.

OBJECTIVE

To summarise the results of patients photopatch tested by members of the North American Contact Dermatitis Group (NACDG), 2009-2020.

METHODS

Retrospective analysis of patient characteristics and PhotoPT results to 32 allergens on the NACDG Photopatch Test Series.

RESULTS

Most of the 454 tested patients were female (70.3%), 21-60 years old (66.7%) and White (66.7%). There were a total of 119 positive photopatch tests. Sunscreen agents comprised 88.2% of those, with benzophenones responsible for over half of them. Final diagnoses included PACD in 17.2%, allergic contact dermatitis (ACD) in 44.5%, polymorphous light eruption (PMLE) in 18.9% and chronic actinic dermatitis (CAD) in 9.0% of patients.

CONCLUSIONS

In 454 patients with suspected photosensitivity referred for photopatch testing in North America, approximately one-fifth had PACD. Sunscreen agents, especially benzophenones, were the most common photoallergens. Other common diagnoses included ACD, PMLE and CAD. Photopatch testing is an important tool for differentiating these conditions.

Pandemic of sensitivity to acrylate containing nail cosmetic among young Israeli women? Result of patch testing 2-hydroxyethyl methacrylate in the European baseline series

BACKGROUND

2-Hydroxyethyl methacrylate (HEMA) was added into the European baseline series (EBS) in 2019. There is limited data regarding the frequency, relevance, and sources of exposure to HEMA.

OBJECTIVES

To investigate the frequency and clinical relevance of positive reactions to HEMA in the EBS in Israel, and explore sources of exposure.

METHODS

Retrospective cohort study that included all patients who underwent patch testing with the EBS in a tertiary center in Israel between 2020 and 2023. Positive reactions to HEMA were stratified by sex, six age groups, and year of study. Sources of exposure to HEMA as well as occupational data were recorded.

RESULTS

A total of 1671 consecutive patients underwent HEMA patch testing, with 135 (8.1%) showing positive reactions to HEMA (130 females, 5 males). The prevalence in women (11.0%) was significantly higher compared to men (1.0%) (p < 0.001). Stratification by age and sex revealed the highest frequency of HEMA sensitivity of 16.7% among women younger than 30 years of age, with odds ratio of 2.3 (95%CI: 1.6-3.3, p < 0.001) compared to older women. There was an increase in frequency among women between the years 2022 and 2023 when compared to 2020-2021 (OR 1.7, 95%CI: 1.5-2.1, p < 0.01) attributable to COVID-19 pandemic and social restrictions. Among men the frequency fluctuations over the study period and age categories were nonsignificant. 111 (84%) were judged to be of clinical relevance and nail cosmetics was responsible for 95% of them. Of 111 patients with relevant reaction (110 females, 1 males), 20 (18%) had occupational contact dermatitis (18 nails stylists, 2 dentists). Other culprit products included sanitary pads (n = 4), medical adhesives (n = 3), and paints (n = 2).

CONCLUSION

We report the highest frequency of HEMA sensitivity to date of 8.1%, that was most common among young women and in vast majority of cases was attributable to nail cosmetics. Our findings reflect the popularity of nail cosmetics in Israel as well as the global trend of increasing sensitivity to (meth)acrylates.

Is the Use of the Extended (Meth)acrylate Series - Nails Justified? Characterization of Nail Acrylate Allergy in a Tertiary Medical Centre

Methacrylate allergy is a common cause of allergic contact dermatitis, and its incidence has surged over the past decade. Consequently, the primary sensitizing agent, 2-hydroxyethyl methacrylate, was recently added to the European Baseline Series of contact allergens. This study aimed to assess the added value of testing for allergens included in the (Meth)Acrylate Series - Nails, in addition to 2-hydroxyethyl methacrylate, as well as to characterize patients who may benefit from more extensive testing. A retrospective analysis of medical records of patch-tested patients was conducted between June 2013 and July 2022. Among the 3,828 patients who underwent patch testing, 396 were tested with the (Meth)Acrylate Series - Nails; 153 (38.6%) of those patients tested positive for at least 1 acrylate. The most common hapten was 2-hydroxyethyl methacrylate (85.6%), followed by hydroxypropyl methacrylate (85.0%) and ethylene glycol dimethacrylate (80.4%). In our study, 22/153 patients (14.4%) would have been missed if tested only for 2-hydroxyethyl methacrylate. The analysis showed that including hydroxypropyl methacrylate and ethylene glycol dimethacrylate improved detection rate to 98%, rendering the use of the entire tray unnecessary in most cases.

Contact allergy to neomycin in consecutively patch tested Danish eczema patients from 2000 to 2023: A cross-sectional study

BACKGROUND

Neomycin is an aminoglycoside antibiotic that may cause contact allergy. It was withdrawn as a medicine for human use in Denmark in October 2009 but is still found in some vaccines.

OBJECTIVES

To identify time trends in contact allergy to neomycin in the period from 2000 to 2023.

METHODS

A cross-section study of patients ≥18 years consecutively patch-tested with neomycin sulfate (20% in pet.) at Gentofte Hospital, Denmark, during the period 2000-2023 was conducted.

RESULTS

The overall prevalence of contact allergy to neomycin was 1.4%. The prevalence was significantly lower in the period '2010-2023' (1.2%) than in '2000-2009' (1.8%) (p < 0.005). Contact allergy to neomycin was significantly positively associated with facial dermatitis and age >40 years, and significantly negatively associated with occupational dermatitis and hand dermatitis. No changes in sex, occupational dermatitis, atopic dermatitis, hand dermatitis, leg dermatitis, facial dermatitis, or age > 40/≤40 (the MOAHLFA-index) were identified when comparing neomycin contact allergic-patients in the two periods '2010-2023' and '2001-2009'.

CONCLUSION

Neomycin is a rare cause of contact allergy in Denmark with a significantly lower prevalence following its withdrawal as a medicinal product for human use in Denmark in 2009.

Cost-effectiveness of patch testing allergens within the same group: A computational approach to optimize formaldehyde-related allergen selection

BACKGROUND

Patch testing for multiple cross-reactive allergens for allergic contact dermatitis (ACD) may not be necessary because of copositivity.

OBJECTIVES

We evaluated the formaldehyde group allergens to determine the optimal, most cost-effective allergens to test.

METHODS

A retrospective analysis of Mayo Clinic (1997-2022) examined the well-established copositive formaldehyde group: formaldehyde, quaternium 15, hexahydro-1,3,5-tris(2-hydroxyethyl)triazine, diazolidinyl urea, imidazolidinyl urea, toluenesulphonamide formaldehyde resin, DMDM hydantoin, and ethyleneurea melamine formaldehyde mix. Patch Optimization Platform identified which single formaldehyde-related allergen optimally captures patients with clinically relevant ACD. Next, Patch Optimization Platform determined the optimal additional 1, 2, 3, etc. allergens. Cost per patch test was $5.19 (Medicare 2022).

RESULTS

A total of 9832 patients were tested for all listed allergens, with 830 having positive patch test results. Patch Optimization Platform determined that quaternium 15 alone captures 53% of patients with ACD to the formaldehyde group; adding the optimal second allergen (formaldehyde 1%) captures 78%; the optimal 5 top allergens capture >94% of patients. The incremental cost per additional diagnosis increased up to 44-fold as the number of allergens tested increased.

LIMITATIONS

Data are from a single institution, and the cost per test was fixed according to Medicare Part B in 2022.

CONCLUSIONS

For diagnosing ACD, we recommend considering an optimized allergen selection algorithm.

Results of patch testing propolis in the European baseline series: A 4-year retrospective study

BACKGROUND

Propolis was added to the European baseline series (EBS) in 2019.

OBJECTIVES

To investigate the frequency and relevance of positive patch tests to propolis in the EBS and to study co-reactivities.

PATIENTS AND METHODS

Retrospective study in patients patch tested between June 2019 and November 2023 in a university hospital in Amsterdam, The Netherlands.

RESULTS

Of 3134 consecutive patients, 299 (9.5%) had a positive reaction to propolis 10% pet. Only nine reactions (3%) were judged to be clinically relevant. There were significant co-reactivities to Myroxylon pereirae resin (balsam of Peru), colophonium, fragrance mixes 1 and 2, and to limonene and linalool hydroperoxides. A steep increase in rates of positive reactions to propolis was observed from 2020 to 2023. This was highly likely the result of the replacement of Chinese propolis with Brazilian propolis by the manufacturer.

CONCLUSIONS

Positive patch tests for propolis are very frequent in Amsterdam, but only a few of these reactions are relevant. Most are probably (pseudo-)cross-reactions in patients with fragrance allergies. Propolis in the EBS has very limited value for dermatologists and patients in The Netherlands. Changes in patch test materials should be provided to all users to avoid misinterpretation of patch test results.

Patient-Reported Association Between COVID-19 Infection or Vaccination and Onset of Allergic Contact Dermatitis®

Background: Over the course of the COVID-19 pandemic, our clinic has encountered numerous patients who report that either COVID-19 vaccination or infection was the precipitating event for their development of allergic contact Dermatitis® (ACD). Up to this time, there is no formal investigation regarding COVID-19 vaccination or infection causing ACD. However, there have been several registry-based case series of associated dermatoses after COVID-19 infection or vaccination. Objective: This study aimed to describe patient-reported associations between COVID-19 infection or vaccination and onset of ACD. Methods: A single-center retrospective noncomparative chart review of 1073 patients patch tested at the Park Nicollet Contact Dermatitis® Clinic (Minneapolis, MN) from March 1, 2020, to March 1, 2022, was performed. Results: Of 1073 patients included in our study, 5 patients (0.47%) reported ACD symptom onset after COVID-19 infection and 12 patients (1.11%) reported onset after COVID-19 vaccination. Rates of clinical relevance were not significantly different than the general population for those who attributed ACD to COVID-19 infection or vaccination. Conclusions: To our knowledge, this is the first study in the literature investigating the potential association between COVID-19 vaccination or infection and the development of ACD through extensive retrospective chart review.

Occupational Contact Dermatitis in Construction Workers: A Retrospective Analysis of the North American Contact Dermatitis Group Data, 2001-2020

Background: Construction workers (CWs) are at risk for occupational contact dermatitis (CD) owing to workplace exposures. Objective: Determine the prevalence of occupational allergic CD and characterize common occupational allergens in CWs referred for patch testing in the United States and Canada. Methods: Retrospective cross-sectional analysis of patients patch tested by the North American Contact Dermatitis Group from 2001 to 2020. Results: Of 47,843 patch-tested patients, 681 (1.4%) were CWs. Compared with non-CWs, CWs were more likely to be male (91.0% vs 30.9%) have occupational skin disease (36.9% vs 11.4%) and have hand involvement (37.2% vs 22.5%) (all P < 0.0001). Of 681 CWs, 60.1% (411) had clinically relevant positive patch test reactions, and nearly 1/3 of CWs (128) had occupationally relevant reactions. Most common occupationally relevant allergens were potassium dichromate 0.25% pet. (30.5%, 39/128), bisphenol A epoxy resin 1% pet. (28.1%, 36/128), carba mix 3% pet. (14.8%, 19/128), cobalt (ii) chloride hexahydrate 1% pet. (14.1%, 18/128), and thiuram mix 1% pet. (14.1%, 18/128). Top sources of occupationally relevant allergens were cement/concrete/mortar (20.4%, 46/225), gloves (15.1%, 34/225), and coatings (paint/lacquer/shellac/varnish/stains) (9.8%, 22/225). Conclusions: Occupational CD in North American CWs is common. In this group, frequently identified etiological sources of occupational allergic CD included metals, epoxy resin, and rubber.

Recognizing and Managing Allergic Contact Dermatitis: Focus on Major Allergens

Patch testing is the reference standard for the diagnosis of allergic contact dermatitis. Identification and avoidance of culprit allergens are essential in the treatment of this disease. Each year, new allergens are identified as emerging or important. The authors discuss allergens that are common, enduring, emergent, incompletely recognized, and controversial for the practicing allergist and dermatologist. This Clinical Management Review will encompass a review of fragrances, preservatives, rubber, acrylates, metals, and medications; their common sources of exposure; controversies in diagnosis and patch testing; management and how to avoid those allergens. This review will also include practical aspects of diagnosis and management and will provide resources that can be used as guidance for physicians and patients on nickel, methylchloroisothiazolinone/methylisothiazolinone, and fragrance, the most common allergens positive on patch testing.

Potassium dichromate sensitivity presenting as tefillin dermatitis: A retrospective cohort study

BACKGROUND

Tefillin are a religious article worn by Jewish men during daily prayer. Tefillin dermatitis secondary to potassium dichromate sensitivity is recognised, but data remain sparse.

OBJECTIVE

To investigate the prevalence and clinical characteristics of tefillin dermatitis.

METHODS

Patients who underwent patch testing with the European baseline series in a tertiary dermatology clinic in 2009-2023 and were diagnosed with tefillin dermatitis were identified by file review and their clinical data recorded.

RESULTS

Of 1679 consecutive male patients tested, 25 (1.49%) were diagnosed with tefillin dermatitis, accounting for 15.34% of all potassium-dichromate-positive patients (163/1679). Mean pre-symptomatic duration of tefillin use was 38 ± 16.9 years, and mean follow-up time, 3.1 ± 2.9 years. Patients presented with an eczematous rash on body areas in direct contact with the leather box or straps of the tefillin. An id reaction was noted in 32%, and sensitivity to other leather accessories, in 44%. Fourteen patients (56%) switched to chromate-free tefillin: symptoms resolved completely in 11 (79%) and partially in 2.

LIMITATIONS

Retrospective cohort design.

CONCLUSION

This is the largest study to date of tefillin dermatitis caused by sensitivity to potassium dichromate used in leather production. Prognosis after switching to chromate-free tefillin was good-to-excellent. Tefillin dermatitis may be more prevalent than previously thought.

Comorbid Scenarios in Contact Dermatitis: Atopic Dermatitis, Irritant Dermatitis, and Extremes of Age

Contact dermatitis (allergic and irritant) occurs when the skin encounters haptens that elicit a T cell-mediated hypersensitivity reaction (allergic) or a nonimmunologic, toxic reaction (irritant). Patch testing is the reference standard for diagnosing allergic contact dermatitis (ACD), although positive results are not always relevant. Therefore, the definitive diagnosis of ACD requires an astute clinician able to connect the results of patch testing appropriately with the clinical history and the cutaneous examination findings. Comorbid conditions such as atopic dermatitis can confound the accurate diagnosis of ACD because of the similarities in clinical presentation. Furthermore, both extremes of age can further challenge the diagnostic specificity of ACD owing to the maturing immune system and the space limitations present when the very young are patch tested. The goal of this Continuing Medical Education article is to discuss the challenges of diagnosing ACD in patients with unique comorbidities such as atopic dermatitis, given the morphologic similarities, and when to patch test these patients. Diagnosis of ACD will also be discussed in very young patients with a focus on patch test allergen selection despite the limited geographic space. The most common allergens reported in very young and old patients will also be discussed.

Managing Contact Dermatitis Without Patch Testing

Allergic contact dermatitis (ACD) is a common skin condition caused by contact with an exogenous agent that elicits an inflammatory response. Patch testing (PT) is considered the gold standard for diagnosing ACD. Unfortunately, PT may not be available to some patients due to insurance and financial limitations, contributing to health care disparity and leaving patients with undiagnosed, incompletely managed dermatitis that can have further detrimental health and occupational effects. For other patients, PT is precluded by lack of availability of specialist/expert care, comorbid medications, or diffuse disease. This article will present a patient with ACD and will work through the differential diagnosis and share strategies for empiric avoidance of suspected/common triggers. The epidemiology of ACD with respect to race and ethnicity, considerations for affordability of hypoallergenic products, access to testing, and the need for future research are addressed in this article.

Allergen content of popular chemical hair relaxers: A product analysis

BACKGROUND

Chemical hair relaxers are widely utilized by black women, yet little research exists on the allergens present in these products.

OBJECTIVE

This study aims to investigate allergen prevalence in the most popular chemical hair relaxers.

METHODS

We analysed 41 products from five major retailers, identifying allergens through ingredient lists and comparing them to the 2020 American Contact Dermatitis Group Core allergen series.

RESULTS

The most common contact allergens in chemical relaxers include propylene glycol, cetyl steryl alcohol, fragrance, D/L-a-tocopherol, tea tree oil and cocamidopropyl betaine.

CONCLUSION

Understanding allergen exposure in products used by individuals with textured hair is needed for managing contact dermatitis in diverse populations. This analysis underscores the presence of potential allergens in hair relaxers, emphasizing the importance of dermatologists' awareness and patient scrutiny of ingredient lists.

Supplemental Patch Testing Identifies Allergens Missed by Standard Screening Series

Background: Supplemental patch testing is an adjunct to standard patch test screening series. Objective: To determine the demographics, characteristics, frequency, relevance, and interpretation of patch test reactions for supplemental patch testing. Methods: Retrospective study of patients tested 2017-2020 with North American Contact Dermatitis Group (NACDG) and supplemental screening series (Supplemental Series A [SSA], Supplemental Series B [SSB]). Demographics, characteristics, reaction strengths, relevance, and final interpretation were recorded. Results: Cohort included 791 patients; 73.5% female, 68.6% age >40 years. 74.1% were White, 15.2% Black, 5.7% Asian, and 1.5% Hispanic. The most common Dermatitis sites were scattered/generalized (27.2%), face (24.0%), and hands (23.5%). For 2017-2018 and 2019-2020, respectively, 82% (318/388) and 78.4% (316/403) had ≥1 "allergic" reaction. In addition, 13.5% (52/385) and 11.7% (47/403) had SSA reactions, and 38.1% (115/302) and 31.5% (101/321) had SSB reactions. In the 87 (2017-2018) and 99 (2019-2020) patients with negative NACDG testing, 17 (19.5%) and 12 (12.1%) had supplemental reactions. Of the 34 supplemental allergens with reaction frequency ≥1%, 58.8% (20/34) are not part of the American Contact Dermatitis Society 90 (2020) or NACDG 2021-2022 screening series. The highest frequency allergens from this group were dodecyl and octyl gallate, cinnamic alcohol, phenyl salicylate, hexahydro-1,3,5-tris-(2-hydroxyethyl) triazine, and abitol. Conclusions: Supplemental patch testing identifies additional relevant allergens in patients with suspected allergic contact Dermatitis.

Clinical relevance of doubtful reactions in patch testing: A single-centre retrospective study

BACKGROUND

Doubtful reactions in patch testing are infrequently reported in the literature; however, recent reports have suggested they be assessed with the same scrutiny as stronger reactions.

OBJECTIVE

Assess the clinical relevance of doubtful reactions in patch testing.

METHODS

Retrospective study of 1514 patients comprehensively patch tested via the NACDG standard series and additional allergens based on history. The clinical relevance of each reaction was graded based on the NACDG scale: definite, probable, possible, past, unknown and irritant. Reactions were considered 'unique' if an additional mild-to-strong reaction to the same chemical at a different concentration was not observed.

RESULTS

68.9% (1043) of patients demonstrated at least 1 doubtful reaction. Of 4453 total doubtful reactions, 92.2% (4106) were unique. Only 3.3% (137) and 12.2% (500) of these were determined to be of definite or probable clinical relevance respectively. 'Fragrance' was the most common allergen family present among the unique definite doubtful reactions (37). However, 24 (64.9%) of these also had a stronger reaction to another fragrance. Cocamidopropyl betaine was the second most frequent allergen demonstrating definite doubtful reactions (27) and unique in 85.2% (23) of cases. Methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) was most prevalent (36) but less frequently unique (58.3%, 21).

CONCLUSIONS

Doubtful reactions may not be as impactful to clinical decision making as theorised in the literature. Few demonstrate definite clinical significance, and many have related stronger reactions that capture them for clinical purposes. Identification of doubtful reactions to cocamidopropyl betaine and MCI/MI may be of greatest significance as they most frequently were not supported by stronger reactions.

Common contact allergens implicated in frontal fibrosing alopecia found in over-the-counter hair growth serums and solutions

Background

Frontal fibrosing alopecia (FFA) is a form of lichen planopilaris with an undetermined etiopathogenesis, predominantly affecting women. There is conflicting evidence as to whether contact allergens may play a role in the underlying etiology or progression of FFA.

Objective

The aim of this study is to find the most common products that patients search for online, identify contact allergens present in these advertised over-the-counter hair products, and suggest their role in the development or exacerbation of FFA.

Methods

We reviewed current research on this topic and then investigated common allergens found in over-the-counter hair products commonly used for hair regrowth.

Results

FFA's exact etiopathogenesis remains vastly unknown, however, current literature has reported an association between inflammatory skin conditions and FFA.

Limitations

The lack of published data on the function of contact allergens in FFA placed restrictions on our study.

Conclusion

A survey-based analysis with a larger cohort is needed to further interpret the relationship between product use and FFA presentation based on contact allergens. More research on possible etiopathogenesis and the relationship between contact dermatitis and FFA may prevent further progression of a patient's disease, leading to an improvement in their quality of life.

Trends in contact sensitization, results, and implications from a contact dermatitis clinic in Israel

BACKGROUND

The baseline series includes common allergens, evolves over time, and differs by location. Our study aims to characterize allergen sensitization trends among the Israeli population during the last two decades, compare our results to American and European registries, as well as to highlight significant allergens in additional series outside the European baseline series (OEBS).

METHODS

We analysed patch test results of 2086 patients from a designated contact dermatitis clinic in Tel Aviv between 2019 and 2022, compared them to European and North American registries and to 2156 patch test results conducted in Israel two decades ago.

RESULTS

38.6% of patients had at least one positive reaction to an allergen in the European baseline series (EBS), nickel sulphate (14.6%), fragrance mix I (4.6%), and Methylchloroisothiazolinone methylisothiazolinone (MCI/MI; 3.7%) were the most common among them. N-Isopropyl N-Phenyl-4-Phenylenediamine (NIPPD; 0%), Propolis (0.1%), Sesquiterpene lactone mix (0.1%), and Budesonide (0.1%) elicited a sensitization frequency significantly lower than the proposed threshold for baseline inclusion. Chi-square test revealed a statistically significant decrease (p < 0.05) in the sensitization frequency of fragrance mix I, Formaldehyde, Potassium dichromate, Neomycin sulphate, Myroxylon pereirae, Sesquiterpene lactone, and NIPPD during the last two decades. The overall sensitization frequency to the majority of allergens was lower in our cohort in comparison to the North American and European registries.

CONCLUSIONS

MCI/MI and 2-hydroxyethyl methacrylate-2 (HEMA) are common, relevant allergens, with high SPIN (significance and prevalence index number) and should be better regulated by the authorities. While among the EBS, NIPPD, Propolis, Sesquiterpene lactone, and Budesonide usually do not elicit a positive reaction and therefore should be reconsidered in baseline series, among the OEBS, Chloramphenicol, Quaternium 15, Propyl gallate, and Amerchol L101 have elicited high SPIN values and should be vigilantly examined in the suitable clinical scenario. Significantly lower sensitization frequency to propolis raises the possibility of a protective effect due to early oral exposure among the Israeli population.

Increasing non-cosmetic exposure and sensitization to isothiazolinones require action for prevention: Review

Frequent use of methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) and MI in cosmetic products has been the main cause of widespread sensitization and allergic contact dermatitis to these preservatives (biocides). Their use in non-cosmetic products is also an important source of sensitization. Less is known about sensitization rates and use of benzisothiazolinone (BIT), octylisothiazolinone (OIT), and dichlorooctylisothiazolinone (DCOIT), which have never been permitted in cosmetic products in Europe. BIT and OIT have occasionally been routinely patch-tested. These preservatives are often used together in chemical products and articles. In this study, we review the occurrence of contact allergy to MI, BIT, OIT, and DCOIT over time, based on concomitant patch testing in large studies, and case reports. We review EU legislations, and we discuss the role of industry, regulators, and dermatology in prevention of sensitization and protection of health. The frequency of contact allergy to MI, BIT, and OIT has increased. The frequency of contact allergy to DCOIT is not known because it has seldom been patch-tested. Label information on isothiazolinones in chemical products and articles, irrespective of concentration, is required for assessment of relevance, information to patients, and avoidance of exposure and allergic contact dermatitis.

Declining frequency of sensitization to fragrance mixes I and II: IVDK-data of the years 2012-2021

BACKGROUND

EU Commission Regulation 2017/1410 prohibits using atranol and chloroatranol, the main allergens in Evernia prunastri (oakmoss), and hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) in cosmetic products. Oakmoss absolute is contained in fragrance mix (FM) I and HICC in FM II which are patch tested as screening mixtures in the baseline series.

OBJECTIVE

To describe the time trends of reaction frequencies to both FMs as well as to their components in FM-positive patients.

METHODS

Retrospective analysis of data from the Information Network of Departments of Dermatology (IVDK), 2012-2021.

RESULTS

Positive reactions to FM I (FM II) declined from 9.1% (4.7%) in 2012 to 4.6% (3.0%) in 2021. Full breakdown tests were performed in 24% (FM I) and 31% (FM II), respectively, of the mix-positive patients. From this data, frequencies of sensitization to the 14 single fragrances of FM I and FM II were calculated. For the majority, a decline was noted from 2012/2013 to 2020/2021, for oakmoss absolute 1.9%-0.8% and for HICC 1.8%-0.9%.

CONCLUSION

EU Commission Regulation 2017/1410 was an effective measure. However, our data have some limitations, possibly causing underestimation of sensitization frequencies to fragrances.

Results of patch testing 2-hydroxyethyl methacrylate (HEMA) in the European baseline series: A 4-year retrospective study

BACKGROUND

2-Hydroxyethyl methacrylate (HEMA) was added to the European baseline series (EBS) in 2019. Few recent data are available on the frequency and relevance of positive reactions to this hapten.

OBJECTIVES

To investigate the frequency and relevance of positive patch tests to HEMA in the EBS in a university hospital in Amsterdam, The Netherlands.

PATIENTS AND METHODS

Retrospective study in patients with positive patch tests to HEMA investigated between June 2019 and August 2023.

RESULTS

Of 2927 consecutive patients, 88 (79 women and 9 men; 3.0%) had a positive reaction to HEMA. The prevalence in women was 3.9%, in men 1.0%. Forty-three (49%) reactions were judged to be of current clinical relevance and 21 (24%) of past relevance. In this group of 64 patients with relevant reactions, 18 (28%) had occupational contact with (meth)acrylate-containing products, of who 11 (61%) were nail stylists. In 46 patients with non-occupational allergic contact dermatitis, 31 (67%) had allergic reactions to nail cosmetics. Glues and glue-containing products accounted for 22% of the materials causing allergic contact dermatitis and dental products for 8%.

CONCLUSIONS

Allergic reactions to HEMA are very frequent in women investigated in Amsterdam. Nearly two thirds of cases were caused by nail cosmetics.

Allergic or Not: Final Interpretation of Doubtful Patch Test Reactions From the North American Contact Dermatitis Group, 2019-2020

Background: Doubtful patch test reactions generally do not meet criterion for positivity in patch testing. However, the North American Contact Dermatitis Group (NACDG) allows for doubtful reactions to be coded with a final determination of "allergic/positive" based on the temporal pattern, appearance, known characteristics of the allergen, and/or other supportive patch test reactions. Objectives: To analyze NACDG data from the 2019-2020 patch test cycle to identify patterns in the interpretation and relevance of doubtful reactions. Methods: The frequency and proportions of doubtful reactions were tabulated and analyzed for patterns. Statistical analyses were limited to allergens with ≥30 doubtful reactions to ensure adequate sample size. Results: Of patch-tested patients, 31.9% (1315/4121) had ≥1 doubtful reaction. Of 2538 total doubtful reactions, 46% (n = 1167) had a final interpretation of "allergic/positive." The allergens with the highest proportion of doubtful reactions at the final visit were hydroperoxides of linalool 1% (4.5%), fragrance mix I 8.0% (3.9%), and cetrimonium chloride 0.5% (3.4%). Methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) 0.02% (P < 0.001), MI 0.2% (P < 0.001), nickel sulfate hexahydrate 2.5% (P = 0.001), and neomycin sulfate 20.0% (P = 0.003) doubtful reactions were more likely to be interpreted as allergic than nonallergic. Methyldibromoglutaronitrile/phenoxyethanol 0.2% (P < 0.001), oleamidopropyl dimethylamine 0.1% (P < 0.001), formaldehyde 2.0% (P < 0.001), cetrimonium chloride 0.5% (P < 0.001), benzophenone-4 (sulisobenzone) 10% (P < 0.001), iodopropynyl butylcarbamate 0.5% (P < 0.001), cocamidopropyl betaine 1.0% (P = 0.002), and benzisothiazolinone 0.1% (P = 0.012) doubtful reactions were less likely to be interpreted as allergic. Of the 1167 doubtful reactions interpreted as allergic, 84.9% had current relevance. Conclusions: Doubtful reactions were common and approximately one half were coded with a final interpretation of "allergic/positive." Of those, most were clinically relevant. MCI/MI, MI, nickel, and neomycin were more likely to be interpreted as allergic.

Analysis of Contact Allergens in Polyvinyl Chloride Examination Gloves in the United States

Background: Polyvinyl chloride (PVC) gloves are recommended as a safe alternative for patients with rubber accelerator allergy. However, allergic contact dermatitis to other chemicals in PVC gloves has been reported. Objective: To analyze single-use PVC medical examination gloves in the United States for the presence of potential contact allergens. Methods: Using liquid chromatography-mass spectrometry, 20 unique PVC gloves were analyzed in triplicate for 6 chemicals: benzisothiazolinone, bisphenol A, mono(2-ethylhexyl) maleate, tricresyl phosphate, triphenyl phosphate, and triphenyl phosphite. Results: All 20 PVC gloves contained detectable quantities of benzisothiazolinone (range, 0.001-1.48 parts per million [ppm]), bisphenol A (0.01-0.11 ppm), triphenyl phosphate (0.01-2.11 ppm), and triphenyl phosphite (0.001-0.22 ppm). Eighteen (90%) gloves contained mono(2-ethylhexyl) maleate (0.001-0.14 ppm) and 3 (15%) contained tricresyl phosphate (0.001-0.002 ppm). Conclusions: Known allergens were present in all 20 PVC gloves. However, the detected levels were mostly low and their relationship with sensitization and elicitation thresholds requires further study.

More than just methylisothiazolinone: Retrospective analysis of patients with isothiazolinone allergy in North America, 2017-2020

BACKGROUND

Isothiazolinones are a common cause of allergic contact dermatitis.

OBJECTIVE

To examine the prevalence of positive patch test reactions to isothiazolinones from 2017-2020 and characterize isothiazolinone-allergic (Is+) patients compared with isothiazolinone nonallergic (Is-) patients.

METHODS

Retrospective cross-sectional analysis of 9028 patients patch tested to methylchloroisothiazolinone (MCI)/methylisothiazolinone (MI) 0.02% aqueous, MI 0.2% aqueous, benzisothiazolinone (BIT) 0.1% petrolatum, and/or octylisothiazolinone (OIT) 0.025% petrolatum. Prevalence, reaction strength, concurrent reactions, clinical relevance, and source of allergens were tabulated.

RESULTS

In total, 21.9% (1976/9028) of patients had a positive reaction to 1 or more isothiazolinones. Positivity to MI was 14.4% (1296/9012), MCI/MI was 10.0% (903/9017), BIT was 8.6% (777/9018), and OIT was 05% (49/9028). Compared with Is-, Is+ patients were more likely to have occupational skin disease (16.5% vs 10.3%, P <.001), primary hand dermatitis (30.2% vs 19.7%, P <.001), and be >40 years (73.1% vs 61.9%, P <.001). Positive patch test reactions to >1 isothiazolinone occurred in 44.1% (871/1976) of Is+ patients. Testing solely to MCI/MI would miss 47.3% (611/1292) of MI and 60.1% (466/776) of BIT allergic reactions.

LIMITATIONS

Retrospective cross-sectional study design and lack of follow-up data.

CONCLUSION

Sensitization to isothiazolinones is high and concurrent sensitization to multiple isothiazolinone allergens is common.

Increased rates of contact allergy to selected preservatives in patients with allergic contact dermatitis in Turkey

BACKGROUND

Preservatives are a frequent cause of allergic contact dermatitis (ACD) and have caused numerous epidemics.

OBJECTIVES

The objective of this study is to determine the prevalence of preservative sensitivity, assess the change in the frequency of sensitivity, identify new preservatives with increased sensitivity rates, and evaluate the situation in Turkey by comparing our findings with current literature.

METHODS

A total of 201 patients diagnosed with ACD between 2018 and 2020, were patch tested with the European baseline series and additional seven preservative haptens. The change in the prevalence of sensitivity to each preservative hapten was investigated by comparing the data from the study conducted in our department between 2000 and 2004.

RESULTS

Results showed that 17.4% (n = 35) of the patients were positive to preservatives. Comparison with previous data from 2000 to 2004 revealed an increase in the frequency of sensitization. The most prevalent allergen was methyldibromo glutaronitrile (9.5%), followed by methylchloroisothiazolinone/methylisothiazolinone (6.5%), and methylisothiazolinone (5%).

CONCLUSION

The increase in preservative sensitivity in Turkey is the most remarkable finding. Although MDBGN was prohibited in cosmetic products, MCI/MI and MI are still widely used. Our findings suggest that awareness of preservative sensitivity should be increased and additional precautions should be taken, also in Turkey, regarding the use of preservatives.

A Survey of Skin Reactions Associated With Acrylic Nail Cosmetics, With a Focus on Home Kits: Is There a Need for Regulation?

Background: Sensitization to (meth)acrylates, the most common nail cosmetic allergens, is rising. In recent years, home acrylic nail kits have become easily available. Objective: To investigate the characteristics of individuals reporting skin reactions associated with acrylic nail cosmetics, particularly home kits. Methods: Cross-sectional survey of Facebook nail allergy support groups. Inclusion criteria were self-reported skin reactions associated with acrylic nails and age ≥18 years. Results: There were 199 respondents, nearly all female (99%), mostly white (83%), and 25-54 years old (83%). Seventy-eight percent reported using home acrylic kits, more than half for the first time during COVID-19. They predominantly learned about kits through social media (68%) and received training through websites/online videos (74%). Most home users (83%) first developed skin reactions after starting to use home kits. Compared with nonhome users, significantly more home users reported skin reaction onset within 1 year of use, as well as nail damage (P < 0.05). Conclusions: Among online nail allergy support group members, home acrylic nail kit use was common and associated with earlier development of skin reactions and more frequent nail damage than professional acrylic manicures. These findings raise important questions about the need to regulate home acrylic nail kits.

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.

Sulfites: Allergen of the Year 2024

Sodium disulfite, also known as sodium metabisulfite or sodium pyrosulfite, is an inorganic compound, which may cause allergic contact dermatitis. Sulfites act as antioxidants and preservatives; common sources include food/beverages, pharmaceuticals, and personal care products. Importantly, sulfites are not included in most screening patch test series and thus may be missed as a relevant contact allergen. The American Contact Dermatitis Society chose sulfites as the Allergen of the Year for 2024 to raise awareness about this significant allergen.

The sesquiterpene lactone mix: A review of past, present and future aspects

The sesquiterpene lactones (SLs) are secondary plant metabolites, which are widespread in the Compositae/Asteraceae plant family. The first SLs were detected more than 100 years ago, and allergic contact dermatitis from Compositae has been reported since the beginning of the 1900s, but it was not until the late 1960s and early 1970s that a collaboration between dermatologists, chemists and botanists led to the detection of SLs as the main allergens of Compositae plants. In the 1980s, the SL mix, consisting of equimolar amounts of alantolactone, costunolide and dehydrocostus lactone, was developed as a screening agent for Compositae sensitisation. Today, after inclusion of SL mix in the baseline series, the mean prevalence of reactions in Europe is around 1%, and in North America 0.8%. In countries outside Europe and North America, the prevalence ranges between 0% and 10.7%. The detection rate of SL mix is lower than that of some plant extracts, and ideally, SL mix should be supplemented with a mix of SLs from locally prevalent allergenic plants. The prevalence of positive reactions to SL mix suggests continued baseline testing in most European countries, North America, New Zealand, Australia and probably some Chinese centres.

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.

Negative formaldehyde release from textiles washed with a formaldehyde-containing laundry soap according to manufacturer instructions: An application of chromotropic acid testing

BACKGROUND

Formaldehyde is a common preservative used to prevent microbial growth in water. It can be found in personal care products and household cleaning products, including laundry detergents. Formaldehyde has frequently been recognised as a cause of allergic contact dermatitis, but whether it remains present in textiles washed with formaldehyde-containing laundry detergents is unknown.

OBJECTIVES

This study aimed to utilise the chromotropic acid method (CAM) to assess formaldehyde release from textiles washed with a laundry detergent known to contain formaldehyde.

MATERIALS AND METHODS

Textiles were laundered with a detergent containing calcium formate at four concentrations (0×, 0.5×, 1× and 5× the recommended amount per manufacturer label) and kept wet or allowed to dry. Select textiles were subjected to an additional rinse cycle. Textiles were then tested utilising the CAM. A sample of the pure laundry detergent was also tested using the CAM.

RESULTS

The CAM was positive only for wet textiles washed at 5× the recommended concentration of detergent and pure detergent. All dry textiles were negative.

CONCLUSIONS

Formaldehyde release was not detected from any textiles washed following the manufacturer's recommendations. Once dry, it is likely safe for formaldehyde-allergic patients to wear textiles washed with formaldehyde-containing detergents.