Expanded Series and Personalized Patch Tests for Children: A Retrospective Cohort Study

Prevalence of allergic contact dermatitis in children with and without atopic dermatitis: A multicenter retrospective case-control study

BACKGROUND

As both allergic contact dermatitis and atopic dermatitis (AD) have similar clinical presentations and are characterized by spongiotic dermatitis on skin biopsy, many children with AD are not referred for patch testing and allergic contact dermatitis is underdiagnosed.

OBJECTIVE

To provide updated prevalence data of common contact allergens in children with and without AD.

METHODS

This is a retrospective case-control study using the Pediatric Allergic Contact Dermatitis Registry from 2018 to 2022.

RESULTS

A total of 912 children were included (615 with AD and 297 without AD). Children with AD were more likely to have a longer history of dermatitis (4.1 vs 1.6 years, P < .0001), have seen more providers (2.3 vs 2.1, P = .003), have greater than 1 positive patch test (PPT) result (P = .005), have a greater number of PPT results overall (2.3 vs 1.9, P = .012), and have a more generalized distribution of dermatitis (P = .001). PPT to bacitracin (P = .030), carba mix (P = .025), and cocamidopropyl betaine (P = .0007) were significantly increased in children with AD compared to those without AD.

LIMITATIONS

Technical variation between providers and potential for misclassification, selection, and recall biases.

CONCLUSION

Children with AD are significantly more likely to have PPT reactions and should be referred for evaluation of allergic contact dermatitis and obtain patch testing.

The Added Value of Patch Testing Beyond the Baseline Tray

BACKGROUND

The patch test is the standard for diagnosing allergic contact dermatitis. Standardized trays allow the examination of the most prevalent allergens, whereas customized trays are more appropriate for addressing specific allergens and require expertise. They are therefore usually performed in specialized clinics.

METHODS

We assessed the results of 4355 patch tests performed between 2012 and 2020 in a contact dermatitis clinic located in a large tertiary medical center. All patients were tested using the European baseline series and additional trays as clinically indicated. We assessed the frequency of relevant positive reactions outside the European baseline series. We then examined the added value and number of tests (NNTs) that need to be performed to elicit one relevant positive reaction per tray and common allergens.

RESULTS

Nine hundred fifty-four patients (21.9%) had 1 or more positive relevant reactions; 43.3% tested positive for an allergen outside the European baseline series (OEBS). The acrylate and fragrance trays were highly represented among the positive and relevant reactions OEBS with NNTs of 4.4 and 6.8, respectively. 2-Hydroxyethyl methacrylate is the most prevalent allergen OEBS and is considered a marker for acrylate sensitivity with a high rate of cross-reactions and concordance rate of 85%, justifying its addition to the EBS in 2018. Other highly represented allergens include chloramphenicol, 2-hydroxyethyl acrylate, and Amerchol L-101, a lanolin derivative. The cosmetics and textile trays, although often tested, have relatively low added values of 3.7% and 2.3%, respectively. Surprisingly, the cutaneous adverse drug reaction series tray (CAD-1000) yielded no positive reactions, whereas testing the patients' medication yielded positive results in 10.9% of the cases.

CONCLUSIONS

Expanded patch testing is crucial to accurately diagnose allergic contact dermatitis and almost doubles the number of patients with relevant positive reactions. Acrylate sensitivity is an emerging epidemic with a high positive reaction rate and low NNT, as is sensitivity to the allergens in the fragrance tray. 2-Hydroxyethyl methacrylate is a reliable marker for acrylate sensitivity with a concordance rate of 85%. Chloramphenicol is a common culprit and should be added to the standard tray in countries with a high usage rate. A low NNT was also observed when testing the patients' own cosmetics and medications; this should, therefore, be encouraged. The textile tray yielded a relatively high NNT; however, it should be performed when clinically indicated in the absence of a reliable marker in the EBS.

Changes in Product Use and Quality of Life After Patch Testing in Children With Allergic Contact Dermatitis: A Follow-up Survey

BACKGROUND

Patch testing is the criterion standard to diagnose allergic contact dermatitis (ACD).

OBJECTIVE

This study assessed the value of patch testing for product changes and quality of life in children with ACD.

METHODS

In this cross-sectional survey, we used a questionnaire to follow up with families of ACD patients about changes since patch testing and counseling preferences. Eligible participants were 18 years or younger during expanded series or personalized patch tests at the Washington University School of Medicine from 2007 to 2020.

RESULTS

Of the 43 enrolled participants, most were positive for multiple allergens (63%) and changed personal products after patch testing (71%). Only 26% of the families consistently read product labels before patch testing, compared with 66% after. Patients saw a mean relative reduction of 49% in severity of rash (8.2-4.2 of 10), 46% in interference with activities (5.7-3.1), and 51% in self-consciousness (7.0-3.4) since patch testing. Families gave favorable feedback for counseling on products to avoid (9.4 of 10 average rating of usefulness), product recommendations (8.5 of 10), and chemical names (7.9 of 10).

CONCLUSIONS

Patch testing can lead to meaningful improvements in quality of life for most children with ACD. Counseling on positive results should include discussion of specific products to use and avoid.

Pediatric allergic contact dermatitis. Part 2: Patch testing series, procedure, and unique scenarios

Patch testing is the criterion standard for diagnosing allergic contact dermatitis. Causative allergens differ between children and adults, necessitating the development of pediatric-specific patch test series. The Pediatric Baseline Series was developed in 2018 through expert consensus and includes relevant pediatric allergens that dermatologists can use in practice. Obstacles in patch testing, such as the need for multiple office visits, length of patch application, and avoidance of sweat and water on the testing area, are particularly challenging for the pediatric population, and several strategies are proposed. Aside from formal patch testing, alternatives like the repeat open application test and empiric allergen avoidance can be helpful in children. The key to management of allergic contact dermatitis is allergen avoidance, with emphasis on the need to properly identify causative allergens. Continued data collection through registries allows for a better understanding of the diagnosis and management of pediatric allergic contact dermatitis.

Pediatric contact dermatitis: what's new

PURPOSE OF REVIEW

Allergic contact dermatitis (ACD) was once thought to be rare in children but recent studies have demonstrated that the prevalence of ACD is common and appears to be increasing in children. Current trends including toys, hobbies, and personal care products may play a role in potentially new allergen exposure or resurgence of certain allergens, making ACD a moving target in children.

RECENT FINDINGS

ACD and atopic dermatitis can coexist and certain clinical features can help differentiate ACD from endogenous atopic dermatitis in children. It is important to consider ACD in children with recalcitrant atopic dermatitis or dermatitis with atypical distribution. Patch testing has become a more common practice in children. In 2018, the first expert consensus-derived pediatric baseline series consisting of 38 allergens was proposed to aid in the diagnosis of ACD in children. Comparing recent patch testing data in the pediatric population, the top allergens ubiquitously identified were nickel, cobalt, neomycin, Myroxylon pereirae (balsam of Peru), fragrance mix I, fragrance mix II, methylisothiazolinone, methylchloroisothiazolinone/ methylisothiazolinone, formaldehyde, and lanolin.

SUMMARY

ACD is a common problem in children. Detection through patch testing, avoidance of offending allergens, and prevention of common allergens are the main focus of management of ACD in children.

Delayed patch test reaction to budesonide in an 8-year-old

Topical corticosteroids are an emerging cause of allergic contact dermatitis in children that may often be missed. It is important to consider patch testing with corticosteroids to detect allergic contact dermatitis in patients with persistent or worsening of dermatitis despite topical corticoseroid treatment. However, delayed reactions (>7 days) to topical corticosteroids may occur, leading to false-negative reactions and misdiagnosis. Herein, we report a case of an 8-year-old girl who developed a positive reaction to budesonide on day 12 of patch testing.

Allergic Contact Dermatitis in Children: Recommendations for Patch Testing

PURPOSE OF REVIEW

Allergic contact dermatitis (ACD) affects 20% of children. However, diagnosis of ACD may be underreported in children due to lack of recognition. Patch testing is the gold standard for evaluation of ACD in children but poses unique challenges in this population.

RECENT FINDINGS

Recent studies highlight the significance of ACD and the utility of patch testing in children. Evaluation of ACD in children is difficult and requires knowledge of a child's exposure history, careful selection of allergens, and knowledge of specialized patch testing considerations to minimize irritation and maximize cooperation. Until recently, there were no agreed upon patch test series for children. In 2018, a comprehensive pediatric baseline series was published enabling thorough evaluation of ACD in children (Yu J, Atwater AR, Brod B, Chen JK, Chisolm SS, Cohen DE, et al. Dermatitis. 2018;29(4):206-12). This review provides an overview of the current literature, an update on pediatric ACD, and patch testing methods in children to effectively evaluate and manage ACD.