Allergic Contact Dermatitis Caused by Hydroxyacetophenone in an Eyelid Moisturiser for Sensitive Skin.

Skin barrier impairment is central to irritant (ICD) and allergic contact dermatitis (ACD). Stratum corneum (SC) components cholesterol sulphate (CholSulph), glucosylcholesterol (CholGlc) and natural moisturising factor (NMF) are critical for barrier function, but their changes in ICD and ACD remain underexplored. To measure CholSulph, CholGlc, NMF and IL-1α in patch-induced ICD and ACD and in hand dermatitis (HD) diagnosed as ICD or ACD. SC samples were collected from HD patients undergoing patch testing. Biomarkers were analysed in positive reactions to sodium lauryl sulphate (ICD, n = 44), allergens (ACD, n = 113; nickel, chromium, methylisothiazolinone [MI]), lesional HD skin (n = 45) and control (empty chamber, n = 121). CholGlc was significantly elevated in patch-induced ICD and ACD. CholSulph was increased in ICD and chromium- and MI-induced ACD. NMF decreased in ICD, while IL-1α decreased in ICD and chromium ACD. Chromium induced the strongest response, nickel the weakest. In HD, ICD and ACD showed elevated CholGlc, reduced NMF and IL-1α, with CholSulph increased only in ACD. No biomarker differences were detected between clinical ICD and ACD. Both induced and clinical ICD and ACD show consistent SC biomarker changes reflecting barrier dysfunction, with no differences between clinical ICD and ACD.

Allergic contact dermatitis and irritant contact dermatitis have different pathogenic mechanisms. It is therefore plausible that the epidermal expression of HLA-DR and the invariant chain associated with antigen processing and presentation might differ between allergic contact dermatitis and irritant contact dermatitis. We have quantified the volume of epidermal HLA-DR and invariant chain reactivity and the total epidermal volume in allergic contact dermatitis and irritant contact dermatitis using confocal laser scanning microscopy and indirect immunofluorescence on acetone-fixed 25 microns thick vertical skin sections. Eight nickel allergic patients were patch-tested with 5% nickel sulfate and 8 healthy volunteers were patch-tested with 4% sodium lauryl sulfate. Skin biopsy specimens were taken at 0, 6, 24, and 72 h after application of the patch tests. Sodium lauryl sulfate induced a statistically significant increased epidermal volume at 24 h and 72 h compared to 0 h and 6 h (p < 0.003 and p < 0.001, respectively), whereas an increase in epidermal volume in the allergic contact dermatitis group was not noted until 72 h after patch testing with nickel sulfate compared to 0, 6 h (p < 0.001) and 24 h (p < 0.004). No significant changes in the epidermal volume of HLA-DR reactivity were found at any time point within or between the two groups, nor was there any significant change in the epidermal volume of invariant chain reactivity in the allergic contact dermatitis group. In the irritant contact dermatitis group, however, the epidermal volume of invariant chain reactivity was significantly reduced from 17 +/- 8 x 10(3) microns 3 at 24 h to 9 +/- 3 x 10(3) microns 3 at 72 h (p < 0.04), which was also significantly lower than the 14 +/- 4 x 10(3) microns 3 observed in allergic contact dermatitis at 72 h (p < 0.01). Furthermore, the invariant chain expression was significantly lower than the HLA-DR reactivity in the irritant contact dermatitis group at 72 h (p < 0.001). The decrease of invariant chain reactivity at 72 h in irritant contact dermatitis might reflect an epitope-induced alteration by sodium lauryl sulfate or a down-regulated biosynthesis of the invariant chain due to variance in local cytokine production between allergic contact dermatitis and irritant contact dermatitis.

Irritant and allergic contact dermatitis are common inflammatory skin diseases induced by repeated skin contact with low molecular weight chemicals, called xenobiotics or haptens. Although both diseases may have similar clinical presentations, they can be differentiated on pathophysiological grounds. Irritant contact dermatitis (ICD) is a non-specific inflammatory dermatitis brought about by activation of the innate immune system by the pro-inflammatory properties of chemicals. Allergic contact dermatitis (ACD) corresponds to a delayed-type hypersensitivity response with a skin inflammation mediated by hapten-specific T cells. Recent progress in the pathophysiology of chemical-induced skin inflammation has shown that ICD and ACD are closely associated and that the best way to prevent ACD is to develop strategies to avoid ICD. The immunological diagnosis of ICD or ACD requires investigation of the presence (ACD) or absence (ICD) of antigen-specific T cells. The detection of T cells can be performed in the skin (collected from ACD lesions or positive patch tests) and/or in the blood, particularly by using the enzyme-linked immunospot assay (ELISPOT). This method, recently developed in ACD to metals, offers a new biological tool enabling the immunobiological diagnosis of ACD.

Noninvasive Evaluation of Allergic and Irritant Contact Dermatitis by In Vivo Reflectance Confocal Microscopy

Contact dermatitis is an inflammatory skin disease induced by direct contact of a external agent to the skin. It can be classified into two main types: Irritant contact dermatitis and Allergic contact dermatitis. Irritant contact dermatitis represents a non-specific cutaneous response to the toxic or physical effects of environmental agents, while Allergic contact dermatitis represents a specific type IV hypersensitivity reaction to specific haptens. Both types are characterized by a highly variable clinical presentation that includes erythema, papules, vesicles, bullae, scaling and erosions in acute cases, and papules, plaques, lichenification, hyperkeratosis and fisures in the chronic. Pruritus is a very common symptom most frequently associated with Allergic contact dermatitis but also frequent in Irritant contact dermatitis. Furthermore, occasionally pruritus may be the leading or only symptom that guides the clinician to suspect the diagnosis of Contact dermatitis, as it is in the case of Allergic contact dermatitis of the anogenital region or when the process occurs in the elderly. Although the mechanisms underlying the pathogenicity of the inflammatory cutaneous response in irritant and allergic contact dermatitis has been widely studied, little is known about the mechanisms leading to pruritus. This chapter summarizes the most important aspects of contact dermatitis in these specific situations as well as the last insights into the pathogenicity of pruritus in contact dermatitis.

IntroductionDifferent aspects of quality of life (QoL) of infants and children with atopic dermatitis (AD) are well studied but there is a lack of studies on seborrhoeic dermatitis (SD) and allergic contact dermatitis (ACD). The aim of this study was to compare the impact of SD, ACD and AD on young children. Parts of questionnaires were filled in during the COVID-19 pandemic and therefore we decided to check if the pandemic affected dermatology-specific health-related quality of life (HRQoL) in our patients.MethodsIn this cross-sectional study approved by the local ethics committee of the Kiev City Clinical Dermatovenereologic Hospital parents of children with SD, ACD and AD from birth to 4 years old from the same department of dermatology were asked to fill in the dermatology-specific questionnaire the Infants and Toddlers Dermatology Quality of Life (InToDermQoL). Diagnoses were based on clinical manifestations and anamnesis. The study was carried out from 2018 till 2021.ResultsThe InToDermQoL questionnaire was filled in by 176 parents of children with SD, ACD and AD. Mean total InToDermQoL scores were significantly higher in children with AD than in SD and ACD (P < 0.01). HRQoL of children with AD during the COVID-19 pandemic was significantly worse than before pandemic (41.30 ± 24.40 and 28.51 ± 17.67 respectively, P = 0.02). Scores of the item on ‘sleep problems’ significantly decreased during the COVID-19 pandemic in children with SD (1.19 ± 1.01 and 0.64 ± 0.63, P < 0.05), as did scores of the item on ‘rejection by other children’ in children with AD (0.96 ± 0.98 and 0.20 ± 0.45, P < 0.05).ConclusionsTo the best of our knowledge this is the first study on HRQoL of the youngest children with SD and ACD. In our study children with SD and ACD had comparable but lower impact of skin disease on their HRQoL than children with AD. The COVID-19 pandemic led to more severe HRQoL impairment in patients with AD visiting a dermatology department.

Nickel allergy in the United States: A public health issue in need of a “nickel directive”

Facial dermatitis: Patch test results and final diagnoses

The CXCR3 Activating Chemokines IP-10, Mig, and IP-9 are Expressed in Allergic but not in Irritant Patch Test Reactions

Allergic skin diseases

Reflectance confocal microscopy may differentiate acute allergic and irritant contact dermatitis in vivo

BACKGROUND AND OBJECTIVESContact allergy is associated with a significant morbidity all over the world. This study was performed to investigate the pattern of sensitization by contact allergens in the local population.DESIGN AND SETTINGRetrospective study to investigate patch test reactivity among patients with clinical diagnosis of contact dermatitis who were referred to the allergy clinic at the King Khalid University Hospital, Riyadh, between April 2008 and March 2010.PATIENTS AND METHODSOf the 196 patients referred to the allergy clinic over the 2-year period, 91 (46.4%) patients reacted to one or more patch test allergens, and these patients were included in this study. The study group included 82 (91.1%) of Saudi nationality and 9 (8.9%) patients of other nationalities. The patch test was performed using the T.R.U.E TEST, containing 24 allergens/allergen mixes.RESULTSOf the 91 cases who reacted positively to one or more allergens, 67 (73.6%) were females with a mean age of 37 (8.3 years) and 24 (26.4%) were males with a mean age of 34 (11.6 years). Thirty-three (36.2%) patients reacted to nickel sulfate, 14 (15.3%) to p-phenylenediamine, 13 (14.2%) to p-tert-butylphenol-formaldehyde resin, 13 (14.2%) to thimerosal, and 9 (9.8%) to colophony. Reactivity against the rest of the allergens was not remarkable. A significantly higher percentage of females reacted to nickel sulfate (84.8% vs 15.2% in males; P=.0001), p-tert-butylphenol-formaldehyde resin (92.3% vs 7.7%; P=.0001), and thimerosal (76.9% vs 23.1%; P=.03).CONCLUSIONSPatch test reactivity to nickel sulfate was high. The pattern of contact allergy observed in this study indicates the need for large-scale investigations to identify local allergens responsible for contact allergy and for formulation of policies directed towards avoidance of exposure.

Recognizing photoallergy, phototoxicity, and immune-mediated photodermatoses

Allergic Contact Dermatitis and Patch Testing in Skin of Color Patients.

Allergic contact dermatitis (ACD) is an important diagnostic consideration in the evaluation of patients presenting with vulval dermatoses. Although ACD coexisting with vulval dermatoses is uncommon, identifying and avoiding the allergens can have a positive impact on the management and quality of life of patients. The aim of this retrospective review of patch test data was to identify relevant allergens in patients presenting with vulval dermatoses in two specialist centres. Relevant data were extracted from electronic database and patch test departmental records between 2013 to 2023 from two specialist cutaneous allergy centres. Patch tests were performed in accordance with the International Contact Dermatitis Research Group and European Society of Contact Dermatitis guidelines. Patch test readings were performed on day 2 and day 4, and positive reactions were recorded. In total, 155 female patients with a mean age of 53.4 years were referred for patch testing. Vulval pruritus (37.5%) and vulval eczema (29%) were the two most common presenting complaints for patch test referral. All patients were tested to the standard and anogenital series, and some to extra series including medicaments, cosmetic, plants, acrylates, hairdressing and own products, depending on clinical history. Multiple allergens were identified including metals, topical drugs, fragrances, preservatives, cosmetic constituents and rubber additives. The most common clinically relevant allergens were fragrances (27.4%), preservatives (18.5%), textile dyes (4.5%) and medicaments (2.5%). Interestingly, 9.6% of patients were tested to the acrylate series, but none had a positive reaction. Fragrance allergy was prevalent in patients with a history of vulval lichen planus and lichen sclerosus. Numerous products were implicated in causing the dermatosis, including sanitary pads, wipes, shower gels and topical medications. Overall, 76% of patients noticed improvement after avoidance of relevant allergens. Patients with chronic vulval dermatoses are at increased risk of ACD and should be assessed for possible contact dermatitis. Patch testing is required to identify relevant contact allergens, the most common of which from our cohort include fragrances, preservatives, textile dyes and medicaments. These results are comparable with previous results reported by Woodruff and Vandeweege (Woodruff CM, Trivedi MK, Botto N, Kornik R. Allergic contact dermatitis of the vulva. Dermatitis 2018; 29: 233–43; Vandeweege S, Debaena B, Lapeere H, Verstraelen H. A systematic review of allergic and irritant contact dermatitis of the vulva: the most important allergens/irritants and the role of patch testing. Contact Dermatitis 2023; 88: 249–62). Patient education and follow-up are essential in optimizing treatment and preventing recurrence of vulval ACD.