American Journal of Contact Dermatitis最新文献

Background: Natural rubber latex allergy is a potentially life-threatening, immunoglobin E (IgE) mediated reaction. Despite great strides in identification of high-risk groups, methods for diagnosis remain limited in the United States and most evaluations are performed by allergists. Objective: The objective of this study was to estimate the prevalence of evaluation for latex allergy and association with practice characteristics in United States dermatologists. Methods: A cross-sectional survey of one third of United States Fellows of the American Academy of Dermatology. Results: The survey response rate was 43%. Of responding dermatologists, 17% stated that they evaluate patients for latex allergy, most commonly with a radioallergosorbent (RAST) or use test. Only 3.6% stated that they perform prick or scratch tests for latex allergy in their office, and most of these dermatologists (86%) prepare their own latex prick test solutions. Evaluation for latex allergy was significantly associated with patch testing, photopatch testing, an interest in contact dermatitis, and number of contact dermatitis books owned, but not with number of years in practice. Conclusions: Most United States dermatologists do not evaluate patients for latex allergy, most likely because of lack of available antigens and because methods for diagnosing latex allergy are not familiar to most dermatologists.

In spite of extensive self-regulation of the fragrance industry, fragrance ingredients are still major causes of allergic contact dermatitis. There are indications that the problem is increasing in some countries, and that many nonregulated compounds are involved in the development of allergies. The use of essential oils in fragrance compounds might add both allergenic and carcinogenic compounds to a product and the exact composition of such ingredients is difficult to control. Herein, we propose a simple strategy to decrease the risk of adverse effects of fragrance ingredients in cosmetic products. This strategy consists of four major steps: (1) limit the concentration of fragrance compound in the products, (2) follow legislation and guidelines, (3) limit the concentration of a number of well-known sensitizing fragrance chemicals, and (4) limit the concentration of essential oils and materials with unknown composition. The strategy is discussed as an alternative to animal testing and in relation to other more resource-demanding approaches to the same problem.

Background: Effective toxicologic evaluation of skin sensitization requires that potential contact allergens are identified and that the likely risks of sensitization among exposed populations are assessed. By definition, chemicals that are classified as contact sensitizers have the capacity to cause allergic contact dermatitis (ACD) in humans. However, this hazard is not an all-or-nothing phenomenon; clear dose-response relationships can be discerned and thresholds identified for both the induction of sensitization and the elicitation of ACD. Commonly, these parameters are grouped under the heading of potency, the determination of which is vital for risk assessment. Preclinical testing for sensitization potential is critically important for hazard assessment before human exposure. The murine local lymph node assay (LLNA) is the most recently accepted test method for sensitization hazard assessment. Objective: The aim was to compare potency estimations derived from LLNA data with clinical determinations of relative potency based on human data. Methods: No-effect levels (NOELs) for a range of 21 chemicals were determined from nondiagnostic human repeat patch test studies as reported in the literature. These levels were compared with LLNA EC₃ values, the estimated concentration required to produce a 3-fold increase (positive response) in draining lymph node cell (LNC) proliferative activity. Results: Using available human repeat patch test data, together with expert judgment, the compounds were classified as strong, moderate, weak, extremely weak, or nonsensitizing. Additionally, the potency of each chemical was classified independently based on its LLNA EC₃ value. The results show clearly that LLNA EC₃ values are very comparable with the NOELs calculated from the literature. Moreover, the potency rankings based upon LLNA EC₃ data support their human classification. Conclusion: The present investigations show that the LLNA can be used to provide quantitative estimates of relative skin sensitizing potency EC₃ values that correlate closely with NOELs established from human repeat patch testing and from our clinical experience.

Background: Patch testing is the confirmatory procedure for allergic contact dermatitis. The test requires the application of chemicals under occlusion for approximately 48 hours to maximize penetration, although it can also produce irritation. Photomechanical waves (PW) have been shown to render the stratum corneum transiently permeable and facilitate the delivery of macromolecules into the epidermis. This alternative might reduce prolonged occlusion of the skin to minimize irritancy, while retaining the sensitivity of the test. Objective: PW was used to facilitate the delivery of an allergen into the skin in vivo. Methods: The allergic skin reaction using PW delivery was compared with 5-minute and 21-hour occlusion in a sensitized hairless albino guinea pig model. The pigs were sensitized by intradermal injection of (0.01%) dinitrochlorobenzene (DNCB) and topical administration (0.1%, 1 week later) of the hapten. One month later, testing for the allergic response was performed by the administration with PW of 10 [mu ]L of 0.1% DNCB. Results: Our results show that there was an allergic reaction for the 24 hour occlusion or PW delivery of the antigen. In contrast, no response was observed for the 5-minute occlusion with the antigen. Conclusion: The rapid delivery of antigens with PW can improve the test for the diagnosis of contact dermatitis.

We report 2 cases of allergic contact dermatitis (ACD) to proparacaine and tetracaine. Patient 1 is an ophthalmologist with chronic finger pad dermatitis sensitized to the topical anesthetic proparacaine. Despite discontinuance of proparacaine and substitution with a patch test negative agent, tetracaine, his hand dermatitis persisted. Follow up patch testing documented that acquisition of contact allergy to tetracaine as well as thiuram had taken place. Patient 2 had a periocular eczematous dermatitis with ACD to both proparacaine and tetracaine. Cross sensitization between related topical ophthalmologic anesthetics has been suggested to be a rare occurrence. We suggest that allergic sensitization and possible cross-reaction to topical anesthetics in ophthalmologists and ophthalmologic technicians is an occupational hazard. Chronically eczematized skin might result in increased exposure to contact allergens and result in concomitant allergic sensitization. ACD to topical anesthetic agents among ophthalmologists should be recognized as a potential hazard.

A case of photocontact dermatitis from ketoprofen is described in a 19-year-old woman with a 3-day history of pruritic lesions on the right forearm. Physical examination revealed a 105 [times ] 46 mm, dark reddish lesion consisting of edematous erythema and papules on the extensor aspect of the right forearm. In photopatch testing, positive reactions to as-is (Mohrus compress [Hisamitsu Pharmaceutical Co, Inc, Tosu, Japan]), ketorofen 1% in petrolatum (pet.), suprofen 1% pet., and tiaprofenic acid 1% pet. were seen. We must consider the anatomic sites on which nonsteroidal anti-inflammation medicaments are applied, as well as their effects.

Background: Reports on natural latex allergy have increased steadily during the last 10 years. Latex allergy generally refers to a type 1 reaction to natural rubber latex (NRL) proteins with clinical manifestations ranging from contact urticaria to asthma and anaphylaxis. Previous United States studies on NRL allergy largely have been reported by allergists with little detailed information on hand eczema, contact allergy, or on outcome. The present study was performed from March 1998 to November 1999 with the aim of finding out the prevalence of type IV hypersensitivity to latex in patients with suspected rubber allergy. Materials and methods: A total of 167 patients with hand eczema and contact with rubber products underwent patch testing with the standard screening and rubber components (test series Deutsche Kontaktallergiegruppe), and NRL pure provided by Regent (liquid high ammonia 0.7% NRL, accelerator, and preservative-free latex) between March 1998 and November 1999. The charts of all NRL positive patients are reported with the results of history, prick, patch tests, total IgE, specific IgE to latex (FEIA) test and follow-up data (after 6 months). Results: Four patients (3 men) showed positive patch test results to NRL. One of these patients also reacted to the rubber chemical tetraethylthiuram monosulfide, and another one of these patients revealed a type 1 reaction to NRL, diagnosed by positive reaction to prick test. The other 3 patients with patch test reactions to NRL had negative reactions to prick tests to NRL extracts after 20 minutes. All 4 patients had a positive delayed prick test reaction to NRL. Latex FEIA test result was negative in all 4 patients. The contact eczema healed after elimination of the latex gloves and medical latex devices in all patients. Furthermore, 10 of the 167 patch testing patients (6%) were positive for tetramethylthiuram monosulfide 1%. Conclusion: In the present study with 167 patients, the prevalence of type IV hypersensitivity to latex was 2.4%. We recommend that the patch test with NRL as well as with rubber additives should be performed in patients of suspected contact dermatitis caused by rubber products.

Background: The subject of lichen planus (LP) and dental metal allergy long has been debated. An overwhelming majority of the existing literature focuses on mercury and gold salts in relation to oral lichen planus. Objective: Our objective was to expand current knowledge regarding LP and lichenoid lesions (LL) and dental metal allergy by investigating more metals and investigating cutaneous and genital disease in addition to oral disease. Methods: Fifty-one patients with known LP or LL were patch tested to a series of dental metals. Patients chose to replace their dental metals or make no revision. A telephone survey was conducted after 1 year to determine disease state. Results: Thirty-eight of 51 patients (74.5%) had at least 1 positive reaction. Twenty-five of 51 patients (49.0%) showed sensitivity to at least 1 mercurial allergen. Prevalence data for patients patch tested by the North American Contact Dermatitis Group (NACDG) from 1996 to 1998 was available for chromate, cobalt, gold, nickel, and thimerosal. The prevalence of positive reactions was higher in our group than in the NACDG group for all 5 of these allergens, and statistical significance was achieved for chromate (P = .028), gold (P = .041), and thimerosal (P = .005). Of patients who had a positive patch test reaction to 1 or more metals, 100% (9 of 9) reported improvement after metal replacement, whereas 62.5% (15 of 24) reported improvement without metal replacement. Conclusion: Sensitization to dental metals is more common among LP and LL patients than in routinely tested patients, and might be an etiologic or triggering factor in the disease.

Background: Metal allergies have been linked to body piercing in women, but few studies have explored this phenomenon in men. It has been postulated that nickel/cobalt and nickel/palladium exhibit coreactivity in patients allergic to metals. Objectives: (1) Determine the incidence rate and the source for the induction of metal allergy in 3 groups of men: unpierced, one site[mdash ]pierced, and multiple sites[mdash ]pierced; and (2) evaluate the degree of coreactivity between nickel/cobalt and nickel/palladium. Methods: Men aged 18 to 43 years (n = 118) were patch-tested using the North American Contact Dermatitis Group's protocol to nickel sulfate 2.5%, gold sodium thiosulfate 0.5%, cobalt chloride 1%, and palladium chloride 1%. Results: Eleven (9.3%) subjects had at least 1 positive reaction. When characterized by the number of pierced sites, positive reactions were seen in 2 of 50 (4.0%) unpierced, 3 of 27 (11.1%) one site[mdash ]pierced, and 6 of 41 (14.6%) multiply pierced men. The number of piercings was a statistically significant predictor of metal allergy (P = .04). Four (66.7%) cobalt and no palladium reactions occurred in nickel-positive subjects. The source for the induction of the allergic response was primarily jewelry, which accounted for 5 of 6 nickel allergies and 2 of 3 gold allergies. Silver jewelry was a significant predictor of an allergic response. Conclusion: This study represents the first report that the number of body piercings has positive bearing on the incidence of metal allergy in men. The data also support the theory of coreactivity for nickel/cobalt, but not for nickel/palladium.