Polysensitization in the Spanish Contact Dermatitis Registry (REIDAC): A 2019-2022 prospective study with cluster and network analysis

BACKGROUND

There is still limited clinical-practice data on specific clinical and patch test features, as well as on allergen clusters in polysensitization (PS).

OBJECTIVES

To determine the frequency, relevance, symptoms duration and risk factors in polysensitized patients and to assess possible allergen aggregation.

METHODS

Prospective multicentric study (January 2019-December 2022) conducted in setting of the Spanish Contact Dermatitis Register (REIDAC). Clinical and patch test data of polysensitized and oligosensitized patients were compared, and risk factors of PS were investigated with logistic multivariate regression. Unsupervised hierarchical clustering and network analysis were used to study allergen aggregation in PS.

RESULTS

A total of 10,176 patients were analysed. PS was found in 844 (8.3%). Current relevance was significantly higher in polysensitized patients (p < 0.01). Risk factors for PS were atopic dermatitis (OR: 1.58, 95% CI: 1.24-2.02), age (≥60 years vs. ≤24 years, OR: 1.75, 95% CI: 1.25-2.44) and some special locations (legs vs. face OR: 1.54, 95% CI: 1.05-2.25, hands vs. face OR: 1.46, 95% CI:1.15-1.85, arms vs. face OR: 1.49, 95% CI:1.01-2.20, trunk vs. face OR: 1.40, 95% CI:1.06-1.85). Cluster and network analyses revealed specific-allergen clusters and significant associations, including allergens belonging to metals group, fragrances and botanicals group, topical drugs group, rubber allergens and biocides.

CONCLUSIONS

This study confirms that PS is structured by discernible patterns of specific-allergen clusters and reinforces significant allergen associations in PS. Cross-reactivity and/or concomitant sensitization could explain the formation of allergen clusters in PS.

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.

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.

Effects of a lotion containing probiotic ferment lysate as the main functional ingredient on enhancing skin barrier: a randomized, self-control study

There is an emergent need to develop functional cosmetic ingredients for the topical management of skin barrier function. This study aimed to investigate the efficacy of a lotion containing fermented lysates VHProbi® Mix R for enhancing the skin barrier. In vitro studies demonstrated that fermented cultures of both Lacticaseibacillus rhamnosus VHProbi® E06 (E06) and L. paracasei VHProbi® E12 (E12) had antioxidant capacity, showing promising scavenging capability for 2,2-diphenyl-1-picryl-hydrazyl. The antioxidant capacity of these strains was also demonstrated in the model of Caenorhabditis elegans. In addition, the fermented lysates of both E06 and E12 enhanced the proliferation of HaCaT cells and ameliorated the toxicity induced by Staphylococcus aureus ATCC 25923, hydrogen peroxide, and ultraviolet B radiation in the HaCaT cell models, which simulated the irritants that facial sensitive skin is exposed to. Subsequently, the ingredient VHProbi® Mix R was formulated using four kinds of fermented lysates: E06, E12, Lactiplantibacillus plantarum VHProbi® E15, and Lactobacillus helveticus VHProbi® Y21. A clinical study was conducted to investigate whether a lotion containing VHProbi® Mix R would be beneficial for people to enhance skin barrier. The participants were asked to use the investigational product for 30 days. Several indicators, including transepidermal water loss (TEWL), skin moisturization, and redness were measured at day 0 and day 30 using VISIA®-CR and CK®-MPA systems. Meanwhile, the burden of sensitive skin (BoSS) and self-assessment questionnaires were performed at baseline and endpoint of this study. The study data showed that at day 30, there was a significant decrease in TEWL (P < 0.01), redness measured by CK®-MPA (P < 0.01), and redness profile measured by VISIA®-CR compared with the baseline measurements. Skin moisturization had significantly increased after treatment with the lotion for 30 days. BoSS and self-assessment questionnaires also substantiated that the participants felt a markedly positive change in their sensitive skin. Hence, we hypothesize that applying the topical functional VHProbi® Mix R could confer effective benefits for people with sensitive skin and this represents a promising intervention for enhancing skin barrier.

Quantitative Risk Assessment of Dermal Sensitization Potential Following Use of Shampoo Products Containing the Formaldehyde Releasing Preservative DMDM Hydantoin

Historically, formaldehyde was used as a preservative in personal care products to extend product shelf-life; however, given its skin sensitization potential it has been phased out of use and replaced with formaldehyde-releasing preservatives, such as Dimethyloldimethyl hydantoin (DMDMH). A relationship has been established between positive patch test results following exposure to DMDMH and previous sensitization to formaldehyde. Upon direct contact with the skin, formaldehyde can react with skin proteins and cause an acute inflammatory reaction, which may progress to skin sensitization following repeated exposure. This quantitative risk assessment (QRA) aimed to assess the risk of skin sensitization induction following use of shampoo products containing the maximum allowable concentrations of DMDMH in formulation (1% w/v), translating to a free formaldehyde concentration of 0.02%. To determine a margin of safety (MOS) for exposure to DMDMH from use of shampoo products, consumer exposure levels (CEL) were estimated based on typical use scenarios and then benchmarked against an acceptable exposure level (AEL). The AEL was derived using a weight of evidence approach where a range of no expected sensitization induction levels (NESILs) was utilized. The MOS values for a shampoo product containing 1% DMDMH (.02% formaldehyde) was above 1 for the typical use scenario indicating a low likelihood of skin sensitization induction among healthy individuals. Thus, it can be concluded that shampoo products containing DMDMH at or below current allowable concentrations are not expected to increase the risk of skin sensitization induction.

Development and Validation of an Instrument to Appraise the Tolerability, Safety of Use, and Pleasantness of a Cosmetic Product

Background: Acceptability tests are designed to demonstrate that there is no chance that cosmetics would irritate or distress users in day-to-day situations. Objectives: to develop and validate a tool or scale that dermatologists, general practitioners, and other healthcare professionals can employ to assess a cosmetic product’s tolerability, safety of usage, and pleasantness. Methods: A three-step modified Delphi technique was used in the consensus process. Two rounds of online surveys and a final face-to-face meeting were performed. Fifty experts for the Delphi panel were chosen to reflect a holistic array of expertise and perspectives in pharmacovigilance, dermatology, and cosmetic safety assessments. In round 1, 80 statements and 115 statements related to skin tolerance and cosmetic safety/efficacy, respectively, were distributed to all members of the expert panel. The expert panel was asked to rate the extent to which they agreed with each statement in the questionnaire using a 5-point Likert scale and given a chance to include a remark beside each item. A statement had to receive 80% of the panel’s approval to be accepted. Results: A total of 50 professional experts were recruited in the Delphi questionnaire rounds (response rate = 63%). The expert panel reached a consensus on 30 statements to evaluate skin tolerability and 34 statements to evaluate cosmetic safety and efficacy (agreement rate level ≥ 80%). The experts also proposed a generic, systematic approach that would allow patients to report both functional and physical symptoms in addition to those discovered during an examination (clinical signs). The confrontation of these symptoms determines whether the investigated cosmetic product is ultimately cutaneously acceptable. Conclusion: The tool that was proposed during this study offered good content validity. Future studies are recommended to test the developed tools in practice to evaluate the good skin compatibility and the safety and quality of cosmetics in the UAE and other nations.

Patterns of positive patch test reactions to formaldehyde and formaldehyde releasers at the Finnish Institute of Occupational Health from 2007 to 2020

BACKGROUND

Formaldehyde is an important contact sensitizer. Formaldehyde releasing substances induce positive reactions in formaldehyde-allergic patients, but there are also reactions independent of formaldehyde allergy. In an earlier study, stronger formaldehyde reactions led to more positive reactions to quaternium-15.

OBJECTIVES

To analyze patterns of positive patch test reactions to formaldehyde and different formaldehyde releasers.

METHODS

Patch test files of 1497 patients investigated during the period November 2007-August 2020 were retrospectively reviewed for positive reactions to formaldehyde and its releasers. During the study period, almost all (≥99.3%) patients were tested with a formaldehyde dilution series and six formaldehyde releasers.

RESULTS

Ninety-three patients tested positive to formaldehyde; 80% of these had positive reactions to at least one formaldehyde releaser, most often benzylhemiformal. There were only nine independent contact allergies to formaldehyde releasers. There were only two reactions to 2-bromo-2-nitropropane-1,3-diol and they occurred in formaldehyde-negative patients. In patients with extreme (+++) reactions to formaldehyde, concomitant positive reactions to any of the other 11 investigated formaldehyde releasers were more common than in patients with milder formaldehyde reactions.

CONCLUSIONS

Strong formaldehyde reactions were associated with positive reactions to formaldehyde releasers.

Prevalence and trend of allergen sensitization in patients with nummular (discoid) eczema referred for patch testing: North American Contact Dermatitis Group data, 2001-2016

BACKGROUND

Few studies have examined the relationship between nummular (discoid) eczema (NE) and allergic contact dermatitis (ACD).

OBJECTIVE

To examine trends, associations, and clinical relevance of ACD in patients with NE who were referred for patch testing.

METHODS

Retrospective analysis of 38 723 patients from the North American Contact Dermatitis Group.

RESULTS

Overall, 748 patients (1.9%) were diagnosed with NE; 23.9% had a concomitant diagnosis of ACD. The prevalence of NE fluctuated over time between 2001 and 2016, with no overall change in prevalence in diagnosed NE. In multivariable logistic regression models, NE increased steadily with age and was associated with male sex and Asian and other race/ethnicity, and inversely associated with a history of atopic dermatitis (AD) and hay fever. Patients with NE had lower proportions of one or more positive allergic reactions and lower odds of a positive reaction in multiple individual allergens. The most commonly relevant allergens in patients with NE were formaldehyde 2.0% aq., methylisothiazolinone, quaternium 15, fragrance mix I, and propylene glycol.

CONCLUSION

NE is a heterogeneous disorder with distinct subsets of lesional distributions and a profile of relevant allergens, especially formaldehyde and formaldehyde releasers. Nearly one in four patients with NE had ACD, supporting the role of patch testing in patients with NE.

Diagnosis and Treatment of Sensitive Skin Syndrome: An Algorithm for Clinical Practice

Sensitive skin has traditionally been viewed as a cosmetic problem or as a purely psychosomatic alteration with a major subjective component. Different studies of its pathophysiologic etiology, however, have shown it to be a complex entity that several authors now consider to be a neurodermatological syndrome. Because of this complexity, skin sensitivity can be difficult to diagnose and treat, particularly considering that it may present with another disease. Simple tools applicable to clinical practice are thus necessary to identify and manage this disease as an independent entity. In this study, we perform a practical review of the most recent scientific advances in the area of sensitive skin that justify it being considered an individual entity, and provide tools for its identification and treatment. We propose diagnostic and treatment algorithms based on evidence from the literature and our experience and expertise.

Cutaneous acceptability of a moisturizing cream in subjects with sensitive skin

Background

Topical cosmetic products can cause adverse reactions in some individuals, particularly those with sensitive skin who may develop irritations or allergic contact dermatitis. Evidence suggests that the frequency of self‐reported sensitive skin is increasing in the general population, placing greater importance on clinical testing of topical cosmetics for potential skin reactivity.

Objectives

To confirm the cutaneous acceptability under normal conditions of use of a moisturizing cream in individuals with sensitive skin.

Methods

This was a prospective, single‐center, open‐label, noncomparative clinical trial conducted in female subjects aged 18‐60 years with Fitzpatrick skin phototype I‐IV and confirmed sensitive skin. Subjects applied the moisturizer twice daily to the body and/or face for 21 ± 2 days. Product acceptability was based on the occurrence of adverse events, investigator assessment of skin adverse reactions, and subjects’ self‐reported feelings of skin discomfort.

Results

Thirty‐five female subjects initiated and completed the study; mean age was 43.2 years and most (89%) had Fitzpatrick skin phototype I‐III. No adverse events or skin adverse reactions of erythema, edema, or skin desquamation were observed. There were no participant reports of skin dryness, prickling, or stinging on any occasion. One subject reported a single event of mild itching, which was considered by the investigator as probably not related to study product.

Conclusions

These findings suggest that the moisturizing cream was well tolerated under normal conditions of use and appropriate for topical use on sensitive skin.

Skin acceptability of a cosmetic moisturizer formulation in female subjects with sensitive skin

Purpose

This 3-week, open-label, noncomparative clinical study evaluated the skin acceptability of a cosmetic moisturizer in subjects with sensitive skin, by monitoring adverse events (AEs) and cutaneous discomfort related to normal usage.

Materials and methods

Female subjects aged between 18–60 years, with Fitzpatrick phototype classification I–IV and sensitive skin, verified by a positive reaction on the stinging test at screening, were included. Subjects applied the moisturizer to their face and body twice daily for 21±2 days at home and recorded study product usage and feelings of cutaneous discomfort (eg, dryness, prickling, stinging, and itching) in a diary; any AEs were reported to the clinic. At study end, skin acceptability of the moisturizer was investigator-assessed based on the nature of AEs and subjects’ self-reported feelings of discomfort, and by clinical evaluation of skin reactions in the area of moisturizer application (appearance of erythema, formation of edema, and skin desquamation; scored according to an adapted Draize and Kligman scale). Only subjects with a treatment compliance of ≥80% were included in the final analysis.

Results

In total, 35 subjects initiated and completed the study; all were compliant to the minimum study product usage. Per investigator clinical dermatological assessment at study end, none of the 35 subjects had skin reactions in the area of moisturizer application and there were no reported AEs. One subject reported sensations of mild prickling and itching immediately after applying the moisturizer (not classified as AEs), which spontaneously remitted after complete absorption of the product and were noted only in exposed areas. These events were considered by the investigator as being possibly/probably related to the use of study product; however, no clinical signs of skin reaction were observed in the exposed areas.

Conclusion

This cosmetic moisturizer appears generally well tolerated and suitable for topical use in subjects with sensitive skin.