Prevalence and Trend of Allergen Sensitization in Adults and Children with Atopic Dermatitis Referred for Patch Testing, North American Contact Dermatitis Group Data, 2001-2016

Evaluation of atopic diseases in patients with allergic contact dermatitis

Background: There is controversy on whether allergic contact dermatitis (ACD) is associated with atopy. Research on eczema and the risk of ACD is mixed, and there is sparse literature on other atopic conditions. Objective: Our study examined the prevalence of several atopic conditions, including allergic rhinitis, eczema, asthma, and food allergies in patients with ACD, and compared these to patients without ACD. Methods: We retrospectively reviewed adult patients ages ≥ 18 years with ACD (n = 162) with positive patch testing results and documented any history of atopy, including childhood eczema, asthma, allergic rhinitis, and immunoglobulin E-mediated food allergy. The prevalence of atopic conditions was compared between our ACD cohort and controls without ACD (n = 163) from our electronic medical records system (age and gender matched). Results: Among our patients with ACD, 53 (33%) had allergic rhinitis, 22 (14%) had childhood eczema, 32 (20%) had asthma, and 8 (5%) had food allergies. We observed that the odds of atopy overall (n = 76) in the ACD group compared with the control group were increased (odds ratio [OR] 1.88; p = 0.007). Allergic rhinitis was the highest risk factor (n = 53) with an OR of 12.64 (p < 0.001). Childhood eczema (n = 22) was also increased in the ACD group (OR 2.4; p = 0.026). The odds of asthma and food allergy in the ACD group were also increased; however, the difference was not statistically significant from the control group (OR 1.76 [p = 0.071] and OR 2.76 [p = 0.139], respectively). Conclusion: Patients with ACD had increased odds of eczema, allergic rhinitis, and atopic conditions overall. Asthma and food allergies were not found to have a statistically significant correlation. Larger studies that delve into atopic risk factors in ACD would be important to confirm these findings.

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.

Preservative Contact Hypersensitivity among Adult Atopic Dermatitis Patients

Atopic dermatitis (AD) is a chronic inflammatory disease characterised by an impaired skin barrier. The prolonged use of topical preparations containing medications, emollients, fragrances and preservatives may increase the risk of contact hypersensitivity (CHS). In the Allergy Outpatient Unit of the Department of Dermatology, Venereology and Dermatooncology of Semmelweis University, 5790 adult patients were patch tested between 2007–2021 with the European Environmental Baseline Series according to international standards. Among all the tested adult patients, 723 had preservative CHS (PCHS) and 639 had AD. Among the 723 PCHS patients, 68 (9.4%) had AD; the female to male ratio was 3:1 in this group. Out of 639 AD patients, 68 had PCHS (10.6%). In the AD-PCHS group, 83.8% had CHS to methylisothiazolinone (MI) (tested from 2014), 36.8% to Kathon CG^®, 16.2% to methyldibromo-glutaronitrile, 11.8% to paraben, 7.4% to formaldehyde, 4.4% to para-tert-butylphenol-formaldehyde resin and 1.5% to Quaternium-15. The most common concomitant PCHS combination was Kathon CG^® + MI. Most patients (32.4%) belonged to the age group of 21–30, and skin symptoms affected mostly the limbs and face. The most common other concomitant allergens were nickel, lanolin alcohol and balsam of Peru. Preservatives (especially MI and Kathon CG^®) are important contact allergens in adult AD, mostly among young women. The rate of AD in the PCHS group and the rate of PCHS in the AD group is remarkable; thus, the role of PCHS should be highlighted in the topical therapy and in the prevention of possible AD exacerbations.

Contact allergy in children with and without atopic dermatitis: an Italian multicenter study

Background

Contact allergy and atopic dermatitis (AD) are both common inflammatory T cell‐mediated diseases and many factors may influence the prevalence of contact allergy in AD patients. In children, their possible correlation was debated with conflicting results.

Objectives

The present study aimed to assess the prevalence of contact sensitivity in children and to investigate the association with AD.

Materials and methods

A retrospective multicentre study on children aged from 0 to 14 years patch tested between January 2017 and December 2018 was performed. Children were consecutively patch tested with the SIDAPA (Società Italiana Dermatologia Allergologica Professionale Ambientale) baseline series.

Results

Among the 432 children investigated for contact allergy, 125 (28.9%) showed a positive reaction to at least one of the allergens tested, with a higher prevalence of positive patch test reactions in girls (32.3%) than in boys (25.0%). The most frequent contact allergens were nickel sulphate (10.2%), cobalt chloride (6.7%), methylisothiazolinone (3.7%), fragrance mix‐2 (3.2%), potassium dichromate (2.8%), fragrance mix‐1 (2.1%) and methylchloroisothiazolinone/methylisothiazolinone (2.1%). One‐hundred‐three children (23.8%) suffered from AD showing a higher prevalence of positive patch test (36.9%) compared to children without AD (26.4%).

Conclusions

Despite the topic being still controversial, the present study suggests a consistent prevalence of contact allergy among children with higher sensitivity rate among children with AD than without AD.

Contact allergy to and allergic contact dermatitis from formaldehyde and -releasers: A clinical review and update

This review aims to provide a clinically useful update regarding the role of formaldehyde (FA) and its five main releasers (FRs) quaternium-15, diazolidinyl urea, DMDM hydantoin, imidazolidinyl urea and 2-bromo-2-nitropropane-1,3-diol (bronopol) in contact allergy and allergic contact dermatitis. These ubiquitous preservatives are still often, and sometimes undeclared, present in cosmetics, pharmaceuticals, medical devices, household detergents and chemical (industrial) products. In Europe, the use of free FA and quaternium-15 in cosmetics is forbidden and contact allergy rates have been found to be stable to decreasing. However, FA/FRs still readily provoke localized (e.g., facial/hand), airborne and generalized dermatitis, and may also complicate atopic and stasis dermatitis, or result in nummular dermatitis. Seborrheic-, rosacea- and impetigo-like dermatitis have recently been reported. For a correct diagnosis, FA 2% aq. (0.60 mg/cm² ) should be used, and particularly the FRs bronopol 0.5% pet. and diazolidinyl urea 2% should be patch tested separately in a baseline series. If sensitization to FA occurs, both FA and FRs should preferably be avoided, except perhaps for bronopol in case it tests negatively. If a patient reacts to one or more FRs (such as bronopol, or diazolidinyl/imidazolidinyl urea), but not to FA, then the specific FR(s) should be avoided. This article is protected by copyright. All rights reserved.

Simultaneous patch testing with fragrance markers in the baseline series and the ingredients of fragrance mixes ‐ an update from southern Sweden

Background

Regularly updating the prevalence of fragrance contact allergy (CA) is important. Patch testing with fragrance markers in the baseline series and the ingredients of fragrance mixes (FMs) is still debated.

Objectives

To update the prevalence and clinical characteristics of patients with fragrance CA. To establish the results of patch testing with individual allergens of FMs.

Methods

A retrospective analysis of 3539 patients with dermatitis who were patch tested with the baseline series and FMs ingredients during 2016 to 2020 was performed.

Results

The prevalence of fragrance CA was 13%. About 10% of these patients with fragrance CA would be missed if the individual ingredients were not tested. Unlike hydroxyisohexyl 3‐cyclohexene carboxaldehyde, there was no decreasing trend of CA to Evernia prunastri (oakmoss) extract after the EU regulation came into force. Patients with CA from only one ingredient of the mixes or having a weak positive reaction to the ingredients were significantly missed when tested with only the fragrance markers in the baseline series.

Conclusions

Patch testing with individual fragrance allergens is crucial for experts to expand knowledge in the fragrance CA field. The concentrations of the allergens in FMs may need to be adjusted to detect patients with fragrance CA, since some were significantly overlooked.

Pattern of contact sensitisation in patients with and without atopic dermatitis in an Asian dermatology centre

BACKGROUND

Although the traditional understanding is that contact sensitisation is less frequent in atopic dermatitis (AD) patients, recent studies have shown similar or higher rates of positive patch test results in AD patients.

METHODS

This was a single-centre, ten-year retrospective review on contact sensitisation in patients who underwent patch testing between 2007 and 2017. The aims were to characterise the pattern of contact sensitisation and to ascertain a link between contact sensitisation and AD.

RESULTS

There were 4903 patients (males:females = 1:1.4; mean age 40.1 years old) included. About half (2499, 51.0%) of all patients developed at least one positive reaction. The top five frequent reactions were to nickel sulfate (45.4%), potassium dichromate (16.0%), p-phenylenediamine (13.4%), Myroxylon pereirae (11.8%) and fragrance mix I (11.2%). The overall prevalence of contact sensitisation was not significantly different between patients with or without AD. Patients with AD were less likely to develop contact allergies to budesonide and thiuram mix, and more likely to develop contact allergies to potassium dichromate.

CONCLUSIONS

Contact sensitisation was detected in 50% of patients patch-tested. Nickel sulfate was the most frequently sensitising allergen. The prevalence of contact allergies in atopic patients is comparable to that in non-atopic patients. This article is protected by copyright. All rights reserved.

Contact allergy in a paediatric population observed in a tertiary referral centre in Belgium

BACKGROUND

Contact allergy is increasingly recognized as being important in children with eczema.

OBJECTIVES

To retrospectively analyse the patch test results in children over the past 10 years, aiming to (1) evaluate demographic characteristics and lesion locations, (2) describe frequencies of positive patch test reactions, and (3) investigate the relationship with atopic dermatitis (AD).

METHODS

A total of 329 children were patch tested between January 2010 and December 2019 with the European (children) baseline series and/or other series, and the personal product(s) used.

RESULTS

A total of 119 (36%) children presented with at least one positive reaction. Children with AD had a higher prevalence of positive reactions compared with the non-AD group (P = .002), but without statistically significant difference regarding sensitization to more than one hapten (P = .39). The face (20.2%), hands (19.3%), feet (16.8%), arms (12.6%), and body folds (10.9%) were the most common sites of primary localizations. The most frequent contact allergens were nickel sulfate and linalool hydroperoxide (both 16%), limonene hydroperoxide (13.5%), and para-phenylenediamine (10.9%). No statistically significant difference for nickel sulfate was found between the AD and non-AD group (P = .20).

CONCLUSIONS

Contact allergy in children with eczema was frequently observed in our tertiary referral centre in Belgium as well, confirming the need for patch testing.