Allergic contact dermatitis from natural rubber latex in atopic dermatitis and the risk of later Type I allergy

The aims of the study were to assess whether contact dermatitis in children could be due to a delayed hypersensitivity reaction to natural rubber latex (NRL) and to define risk factors for later occurrence of Type I hypersensitivity to this allergen. Among 1800 children investigated for contact dermatitis, 55 were referred on suspicion of rubber allergy and had patch tests to NRL, as well as prick tests and blood tests for specific immunoglobulin E (IgE). A 2-year follow-up was then carried out. Delayed hypersensitivity to NRL was confirmed in 32 children. Patch testing with NRL proved to be positive, and clinical improvement confirmed the diagnosis and relevance of patch tests. 30 of these 32 patients had associated atopic dermatitis (AD). Prick tests and blood tests for specific IgE to latex were negative at the time of diagnosis. A 2-year follow-up showed that 10 of 27 patients presenting initially with a positive patch test without associated Type I sensitization later developed immediate hypersensitivity. Children with AD are at high risk for allergy to NRL protein. Exclusion of this allergen should be strongly advised in atopics because of the dual risk of dermatitis and later evolution into severe Type I hypersensitivity.     

Fragrance contact allergy: a 4‐year retrospective study

Background: Fragrance chemicals are the second most frequent cause of contact allergy. The mandatory labelling of 26 fragrance chemicals when present in cosmetics has facilitated management of patients allergic to fragrances. Objectives: The study was aimed to define the characteristics of the population allergic to perfumes detected in our hospital district, to determine the usefulness of markers of fragrance allergy in the baseline GEIDAC series, and to describe the contribution made by the fragrance series to the data obtained with the baseline series. Material and methods: We performed a 4‐year retrospective study of patients tested with the Spanish baseline series and/or fragrance series. There are four fragrance markers in the baseline series: fragrance mix I (FM I), Myroxylon pereirae, fragrance mix II (FM II), and hydroxyisohexyl 3‐cyclohexene carboxaldehyde. Results: A total of 1253 patients were patch tested, 117 (9.3%) of whom were positive to a fragrance marker. FM I and M. pereirae detected 92.5% of the cases of fragrance contact allergy. FM II and hydroxyisohexyl 3‐cyclohexene carboxaldehyde detected 6 additional cases and provided further information in 8, enabling improved management. A fragrance series was tested in a selected group of 86 patients and positive results were obtained in 45.3%. Geraniol was the allergen most frequently found in the group of patients tested with the fragrance series. Conclusions: Classic markers detect the majority of cases of fragrance contact allergy. We recommend incorporating FM II in the Spanish baseline series, as in the European baseline series, and using a specific fragrance series to study patients allergic to a fragrance marker.     

Evaluation of efficacy of a skin lipid mixture in patients with irritant contact dermatitis, allergic contact dermatitis or atopic dermatitis: a multicenter study

Disturbances of skin barrier function occur in several skin diseases, e.g., atopic dermatitis (AD), irritant/allergic contact dermatitis (ICD, ACD). Skin barrier damage triggers the production of cytokines that stimulate lipogenesis which may also cause inflammatory processes. The aim of this study was to evaluate the efficacy of a topical skin lipid mixture in the treatment of ICD, ACD and AD. 580 consecutive patients suffering from ICD, ACD or AD were treated with a skin lipid mixture containing ceramide-3 and patented nanoparticles. Patients received the lipid mixture alone or in combination with topical corticosteroids until clearance or for 8 weeks. Both treatment groups statistically improved all parameters considered at week 4 and 8 as compared to baseline. Between the 2 treatment groups, there was a statistically significant difference in favour of combined therapy for (ICD, ACD, AD, respectively): erythema, pruritus and overall disease severity; erythema and pruritus; erythema, pruritus, fissuring and overall disease severity. No statistically significant difference was found for (ICD, ACD, AD, respectively): dryness, scaling and fissuring; scaling, fissuring and overall disease severity; dryness and scaling. Between the 2 ACD treatment groups, there was a statistically significant difference in favour of the skin lipid mixture for dryness. In conclusion, the study shows that balanced lipid mixtures are effective in improving barrier properties and the clinical condition of the skin in contact dermatitis.     

Occupational dermatitis in bakers: a clue for atopic contact dermatitis

6 patients are described who developed contact dermatitis after cereal contact on atopic skin for periods of 2 to 20 years. 2 patients were wheat flour patch-test-positive. They had punch biopsies taken for standard histological and immunohistochemical investigation by labeling with monoclonal antibodies, anti-DR and anti-IgE. Sections showed features of contact dermatitis. There were many dendritic cells located perivascularly in the papilla and in the epidermidis, intensely positive for monoclonal anti-IgE antibody. In control atopic subjects, there were a few perivascular IgE positive cells, probably mastocytes. This study shows that there may be a relationship between some allergens and atopic eczema in patients exposed to them in the course of their work. In some cases, there was a true allergic contact dermatitis, seen through the clinical and histological characteristics, and the results of immunohistochemical study.     

Allergic contact sensitization in the general adult population: a population-based study from Northern Norway

Few studies have so far addressed the prevalence and risk factors for contact sensitization in the general adult population; however, many such studies have been conducted in hospitals. We present the prevalence of contact sensitization in a general adult population and its relationship to potential risk factors like smoking, ear piercing and atopic diseases. 1236 adults (44.2% men and 55.8% women) were randomly selected from a cross-section of the population in Sør-Varanger municipality, Norway, and patch tested with TRUE Test (Pharmacia, Hillerød, Denmark). Contact sensitivity to at least 1 out of 24 allergens was found in 35.4% of the women and in 14.8% of the men. The most common allergens were nickel (17.6%), cobalt (2.8%), thiomersal (1.9%), fragrance mix (1.8%) and colophony (1.2%). All other allergens were observed in 1.0% or less. In women, ear piercing was an important risk factor for nickel sensitization. No such significant correlation was seen in men [in women relative risk (RR) = 3.30, 95% confidence interval (CI) = 2.01–5.43, and in men RR = 1.82, 95% CI = 0.66–5.00], and contact sensitivity was associated with atopic dermatitis (AD) [adjusted odds ratio (OR) = 1.58, 95% CI = 1.04–2.40] and smoking (adjusted OR = 1.42, 95% CI = 1.01–1.99) in women but not in men. The prevalence of contact sensitivity was common in this general population, especially in women. Smoking and AD might be a risk factor for contact sensitization.     

Adhesion molecule profiles in atopic dermatitis vs. allergic contact dermatitis: pharmacological modulation by cetirizine

BACKGROUND: Experimental data suggest that there is an imbalance between Th1 and Th2 cells in atopic dermatitis (AD) skin compared to allergic contact dermatitis (ACD). This imbalance (Th2 and Th1 predominance, respectively) implies the production of different cytokines in these two conditions leading to different expression of adhesion molecules on skin endothelial cells. OBJECTIVE: The expression of VCAM-1 (IL-4/Th2-dependent) and ICAM-1 (INF-gamma/IL-1) on dermal vessels was compared in six patients with AD and six patients with ACD. The effect of cetirizine, a highly selective H1-receptor antagonist on the expressions was studied. METHODS: Six patients with AD were challenged with Dermatophagoides pteronyssimus (DPT patch tests applied to clinically normal skin) and six patients with ACD challenged in the same way with allergens of the European standard series. Skin biopsies at challenged sites were performed before and 6, 24 and 48 h after challenge. The experiment was carried out under double-blind cross-over conditions during a 4-day treatment with a placebo and cetirizine. RESULTS: In AD patients, the scores for both VCAM-1 and ICAM-1 were high before and after challenge. In ACD patients, the ICAM-1 score was high at each experimental time, but the VCAM-1 score, which was significantly lower before challenge, increased at 6, 24 and 48 h after challenge. The administration of cetirizine significantly reduced the VCAM-1 expression in AD patients at each experimental time. CONCLUSION: It is concluded that the increased VCAM-1 expression in AD patients compared to ACD may reflect greater IL-4 and/or IL-13 production in situ. The study also confirms the existence of a modulating effect of cetirizine in vivo on adhesion molecule expression.     

Allergic contact dermatitis to chlorhexidine in pediatric patients

Chlorhexidine is one of the most widely used antiseptics in our environment. Allergic contact dermatitis to chlorhexidine is common in adults, but is quite rare in the pediatric population. Its diagnosis is important because it can mimic other dermatoses common during childhood, and it can also lead to acute immediate hypersensitivity reactions following successive exposures.