P67Hand eczema, skin exposure and glove use in dental technicians

Objective:  Exposure to adhesives and glues is common in occupation. We here analyse the data of patients with suspected contact dermatitis (CD) from glues recorded within the Information Network of Departments of Dermatology (IVDK).
Methods:  Data recorded between 1996 and 2001 within the IVDK were searched for patients who underwent patch testing because of suspected contact dermatitis from glues.
Results:  Overall data of 829 patients were found, among them 336 with occupational skin disease. Allergic CD was diagnosed in 171/336 patients (50.9%), irritant CD in 24.7%. CD was mostly localized on the hands (72.6%), followed by the face (13.4%) and arms (3.9%). By far the most common cause of an allergic patch‐test reaction was epoxy resin (EP): 18.2%(age‐ and sex‐standardized proportion of sensitization) reacted to the standard EP based on diglycidylether of bisphenol A. reactive diluents and hardeners which elicited a positive patch‐test reaction in > 5% of the patients were phenyl glycidylether and 4,4'diamino diphenylmethane respectively. Cresyl glycidylether was positive in 4.9%. (Meth‐)acrylates which showed an allergic patch‐test reaction in >= 5% of the patients were 2‐hydroxypropyl methacrylate, hydroxyethyl acrylate, 2‐hydroxyethyl methacrylate, ethyleneglycol dimethacrylate, BIS GMA and triethyleneglycol dimethacrylate. Colophony was positive in 8.3% and p‐tert‐butylphenol formaldehyde resin in 4.1% of the patients respectively.
Conclusion:  In our collective allergic CD was nearly 2‐fold more frequent than irritant CD in patients with occupational CD from glues, epoxy resin components being the most important allergens.     

P47Contact dermatitis to peppermint and menthol in a transdermal therapeutic system

We describe a case of a 42‐year‐old non atopic man with a history of ano‐perianal eczema in consequence of the use of anti‐haemorroidal ointments and allergic contact dermatitis to Myroxylon pereirae, benzocaine, paraben mix and paraphenylenediamine. He was referred to our Unit for a strong eczematous reaction in the genital area with a marked oedema of the balanoprepuzial region that had appeared some hours after the use of a condom (Settebello‐Hatù® Durex) made of natural latex and containing a retarding cream composed with benzocaine 5%, polyethylene glycol plus glycerin 94,7% and paraben 0,3% as preservative. The suspension of the use of the condom and treatment with a corticosteroid cream healed the eruption in few days. Patch testing with the SIDAPA (Società Italiana di Dermatologia Allergologica, Professionale e Ambientale) standard series, an additional rubber series, a piece of the rubber's condom washed clean of cream and the condom's cream gave positive reactions to Myroxylon pereirae, benzocaine, paraben mix, paraphenylenediamine and condom's cream. Further patch test with the other ingredients of condom's cream was negative as well as latex prick test. We discuss about the ethiologic agents and the most useful diagnostic test in allergic contact dermatitis condom‐related and the preventive measures that should be adopted.     

Allergic paraben and benzyl alcohol hypersensitivity relationship of the "delayed" and "immediate" varieties

From a review of the literature, and the results of scratch, intracutaneous and subcutaneous injections of patients with parbens and benzyl alcohol sensitivity of the delayed type characterized by allergic contact dermatitis and strongly positive patch patch tests, it would appear that such sensitivity is not usually accompanied by the immediate urticarial type of allergic sensitivity. This communication concerns itself with results of testing patients with clinical sensitivity and positive patch test reactions to the parabens or benzyl alcohol with scratch, intracutaneous and subcutaneous injections of these preservatives in order to determine the relationship of the "delayed" type of allergic hypersensitivity to the parabens and benzyl alcohol with the "immediate" variety of hypersensitivity. The parabens and benzyl alcohol are widely employed as preservatives for many allergenic extracts used in scratch and intracutaneous testing. In addition, these preservatives are used in injectable corticosteroid medicaments and in local anesthetic solutions. In order to determine whether the presence of these preservatives in allergenic extracts would produce false positive scratch or intracutaneous tests or might produce an immediate, urticarial or anaphylactic reaction in patients with allergic contact dermatitis and positive patch test reactions to these preservatives, two patients with positive patch test reactions and allergic contact dermatitis to the parabens and two with similar benzyl alcohol sensitivity were tested in the manner detailed in the following case reports.     

P48Actual risk of contact dermatitis in hairdressers

In order to know the actual risk of contact dermatitis in hairdressers, we studied, from 1994 to 2003, 300 hairdressers of a total of 7510 patients seen in our Department of occupational skin diseases. Most of them were women (93%) with a mean age of 23.7 years. A positive patch test response to one or more of the allergens tested was presented by 215 patients (71.7%). Occupational allergic contact dermatitis was diagnosed in 174 cases (58%). The most frequent sensitizations showed by positive patch test response were to: PPD (54.3%), 4‐aminobenzene (40.7%), nickel (36.7%), disperse orange (17%), p‐toluene‐diamine (15.3%), ammonium persulfate (14.3%), aminophenoles (14.0%), acid thioglycolic (12.7%) and kathon (10.3%). Irritant contact dermatitis (20%), no occupational allergic contact dermatitis (5.3%), atopic dermatitis (6.7%) were some of the other diagnoses between the hairdressers. We compare these results with those of a previous study of 379 hairdressers who attended our department from 1980 to 1993, in order to evaluate the effects of the changes in the substances and techniques used in hairdressing and the occupational education in the risk of sensitization in this trade.     

P65Patch testing to plastics in Sheffield

We reviewed our experience patch testing to plastics at the Royal Hallamshire Hospital in Sheffield, England. The department's electronic database was searched from June 2002 to December 2003. In total 434 patients where patch tested to the British Standard Series. All positive reactions to epoxy resin and p‐tert‐Butylphenol‐Formaldehyde resin (PTBF)where recorded. 28 of the patients tested to the Standard Series where also tested to an extended Plastics Series and again positive reactions where recorded. Type‐4 mediated hypersensitivity reactions where seen in, 3 men secondary to epoxy resin, 2 men secondary to PTBF and in 1 women secondary to triethylene glycol acrylate. No irritant reactions where recorded. Epoxy resin was thought to be the cause of an occupational allergic hand dermatitis in 2 of the men. The positive reactions in the other patients where felt not to be of current relevance to their dermatitis. Allergic contact dermatitis to plastic appears to be rare in patients attending for patch testing in Sheffield. In particular the frequency of reactions to epoxy resin, a potent sensitizer, is less than 1%. This is perhaps surprising as Sheffield is a large industrial city where exposure to epoxy resins is likely to be common. Hopefully this reflects safe workin practices in Sheffield.     

The CXCR3 activating chemokines IP-10, Mig, and IP-9 are expressed in allergic but not in irritant patch test reactions.

Differentiation between allergic and irritant contact dermatitis reactions is difficult, as both inflammatory diseases are clinically, histologically, and immunohistologically very similar. Previous studies in mice revealed that the chemokine IP-10 is exclusively expressed in allergic contact dermatitis reactions. In the present study, we investigated whether the mRNA expression of IP-10 and the related CXCR3 activating chemokines, Mig and IP-9 are also differentially expressed in human allergic contact dermatitis and irritant contact dermatitis reactions. Skin biopsies from allergic (13 cases) and sodium lauryl sulfate-induced irritant patch test reactions (13 cases), obtained 1-72 h after patch testing, were studied by means of an in situ hybridization technique. Results of chemokine mRNA expression were correlated with clinical scoring, histology, and immunohistochemical data including the proportion of inflammatory cells expressing CXCR3, the receptor for IP-10, Mig, and IP-9, and ICAM-1 and HLA-DR expression on keratinocytes. IP-10, Mig, and IP-9 mRNA were detected in seven of nine allergic contact dermatitis reactions after 24-72 h, but not in sodium lauryl sulfate-induced irritant contact dermatitis reactions. ICAM-1 expression by keratinocytes was only found in allergic contact dermatitis reactions and correlated with chemokine expression. Moreover, up to 50% of the infiltrating cells in allergic contact dermatitis expressed CXCR3, in contrast to only 20% in irritant contact dermatitis reactions. In conclusion, we have demonstrated differences in chemokine expression between allergic contact dermatitis and irritant contact dermatitis reactions, which might reflect different regulatory mechanisms operating in these diseases and may be an important clue for differentiation between allergic contact dermatitis and irritant contact dermatitis reactions.     

Allergic contact dermatitis to 2-bromo-2-nitropropane-1,3-diol in a hydrophilic ointment

Seven patients are described who developed acute allergic contact dermatitis after using Eucerin cream on previously dermatitic skin for periods of time varying from 5 weeks to 2 years. Eucerin was preserved with 2-bromo-2-nitropropane-1,3-diol (BNPD) in 1978 to assist in controlling a problem with Pseudomonas aeruginosa contamination. All of our patients were BNPD and Eucerin patch test-positive. None of them was allergic to formaldehyde or to any other preservative known to be a formaldehyde donor. This was in contrast to other BNPD and other formaldehyde-releaser--sensitive patients we saw in 1979-1980, who often had positive patch test reactions throughout this group of preservatives. BNPD is difficult to patch test with because it is often an irritant, even in low concentrations. We discuss some patch test "lessons" which our experiences with these patients accentuated for us.     

Allergic contact dermatitis to benzyl alcohol in a hearing aid impression material.

A patient with allergic contact dermatitis caused by benzyl alcohol in a hearing aid impression material and in topical medications is described. In addition, the patient had topical and probably systemic corticosteroid allergy. Benzyl alcohol allergy is reviewed. allergic contact dermatitis is the most commonly reported allergic reaction to benzyl alcohol. There is also 1 report of contact urticaria. Balsam of Peru patch tests are frequently positive. Reported allergic reactions to injected benzyl alcohol include generalized urticarial reactions, 1 generalized maculopapular reaction and 1 delayed localized reaction.     

Vulvar dermatoses--irritant and allergic contact dermatitis of the vulva

Irritant and allergic contact dermatitis are commonly seen in patients complaining about itching, burning and irritation in the vulvar area. Irritation often precedes allergic sensitization. Clinically, irritant and allergic contact dermatitis can be difficult to distinguish. Diagnosis is made by history, clinical investigation and patch testing. Recommended patch test series are the standard series, a medicament series, the patient's own topical medicaments, popular remedies and other suspected products. A skin biopsy may be useful to establish the diagnosis of contact dermatitis, but it is usually not helpful for the differential diagnosis between irritant and allergic dermatitis.     

Immunopathological and ultrastructural findings in human allergic and irritant contact dermatitis

The histopathological features of allergic contact dermatitis were compared with those of irritant contact dermatitis in a group of 17 subjects. Each patient received simultaneous patch tests of a known allergen and a standardized irritant (benzalkonium chloride). The cellular changes occurring between 3 h and 7 days after patch test application were studied by light and electron microscopy and immunocytochemistry. No differences were observed between the induced allergic contact dermatitis (ACD) and the irritant contact dermatitis (ICD), either in the responding cell types or the sequence of cellular events. Both reactions showed a predominantly T lymphocyte infiltrate with no polymorphonuclear leukocyte involvement. Apposition of Langerhans cells to lymphocytes in the epidermis was seen in both types of response. Considerable variability in the intensity of reaction to irritant and allergen occurred within individuals. There was no statistically significant difference between the intensity of the reactions to the irritant and the allergen.     

Case of allergic contact dermatitis due to 1,3‐butylene glycol

1,3‐Butylene glycol (1,3‐BG) is widely used in cosmetics, including low‐irritant skin care products and topical medicaments, as an excellent and low‐irritation humectant. We report a case of allergic contact dermatitis caused by 1,3‐BG. A 28‐year‐old woman suffered from an itchy erythematous eruption on her face. By 2 days of closed patch testing, her own cosmetics and many of the hypo‐irritant skin care products showed positive results. A second patch testing showed positive reaction to 1,3‐BG (1% and 5%). 1,3‐BG was a common component in most of the products that had elicited a positive reaction in the first patch testing. Although allergic contact dermatitis due to 1,3‐BG is not so common, we have to consider 1,3‐BG as a possible contact allergen in the patients presenting with allergic contact dermatitis due to various cosmetics.     

Topical antioxidants protect the skin from chemical-induced irritation in the repetitive washing test: a placebo-controlled, double-blind study

Background. There is increasing evidence that reactive oxygen species play an important role in the development of both irritant and allergic contact dermatitis. Objectives. To assess the potential of topical antioxidants to prevent the development of experimentally induced irritant contact dermatitis. Methods. We evaluated the effect of a cream containing a combination of antioxidants on sodium lauryl sulfate-induced irritant contact dermatitis in the repetitive washing test. As readout parameters for skin barrier function and cutaneous inflammation stratum corneum hydration, cutaneous blood flow and transepidermal water loss were assessed in 25 volunteers with bioengineering methods. Results. In comparison with the cream base and a frequently used barrier cream, the antioxidant cream had high radical scavenging activity and effectively protected the skin from chemical-induced irritation. Conclusions. The superiority of the cream with antioxidants to the cream base suggests that reactive oxygen species, at least in part, play a role in the development of irritant contact dermatitis.     

FS11.1Primula obconica – a falling allergen

Objective:  We believe the incidence of primula contact allergic dermatitis has fallen since the introduction of primin‐free primula onto the European market and thus our study aims were twofold. Firstly to see if the incidence of primula contact allergic dermatitis was truly on the decline and secondly to confirm the presence and document retailers' knowledge and awareness of primin‐free primula in the UK.
Methods:  A questionnaire was sent to 22 contact dermatitis departments throughout the UK and Ireland looking at the number of primin positive patch tests in the years 1995/96, 1998, 2000 and 2002 compared with the total number of patch tests. 10 seed suppliers and 12 plant retailers were asked to complete a telephone survey.
Results:  We showed a significant fall in the yearly incidence of contact allergy to primin from 0.785% in 1995/96 to 0.457% in 2002. This downward trend was statistically significant (p = 0.001). The telephone survey showed 90% of seed suppliers were aware that the older varieties of P. obconica could cause an allergic reaction whereas only 60% of them were aware that new primin‐free varieties were now being bred. 50% of suppliers were in fact selling these primin‐free varieties with 60% of them stocking a primin‐free variety exclusively. 90% of retailers were not currently selling any variety of P. obconica.
Conclusion:  Our study shows that the incidence of primula contact dermatitis is falling. The overall trend is moving towards primin‐free varieties provided they continue to be horticulturally viable long term.     

Retrospective survey of patch testing at department of dermatology and venerology, zagreb university hospital center in zagreb, croatia

Epicutaneous (patch) test is a standard test to confirm contact allergy. During a six-year period (1998-2003), contact allergic dermatitis was diagnosed in 4132 (65%) of 6341 patients using standard patch test with a Croatian series of allergens according to the International Contact Dermatitis Research Group (ICDRG). The most common clinical diagnoses related to contact allergy (male; female) were contact allergic dermatitis (65.4%; 72.2%); atopic dermatitis (15.9%; 11.7%); contact irritant dermatitis (7.0%; 6.6%) and nummular eczematoid dermatitis (4.2%; 2.4%). According to occupation, positive patch test reaction was most commonly observed in workers, whereas 65% of patients showed positive reactions to one or more substances. There was an increased frequency of positive patch test reactions to potassium dichromate, nickel sulfate, thimerosal and neomycine sulfate, along with a significant decrease in the frequency of positive patch test reactions to cobalt chloride, carba mix, wood tars, detergents, parabens mixture, urushiol and rubber mixture. We strongly recommend keeping up-to-date with the epidemiology of contact allergy in Croatia.     

Studies on contact dermatitis in stomatological staff

84 patients with contact dermatitis (38 dentists, 18 dental nurses and 28 dental technicians) were studied. All were patch tested with standard patch test series of the CMEA countries and with some professional allergens. 31 (36.9%) of them had allergic occupational contact dermatitis and 39 (46.2%) had irrtiant contact dermatitis. The highest prevalence of irritant contact dermatitis was found among dental surgeons. The percentage of atopics in the group of patients with irritant contact dermatitis was twice greater compared to that in the group of patients with allergic contact dermatitis. The contact allergens most frequently encountered were acrylic compounds, disinfectants (eugenol, thymol, trioxymethylene) mercury compunds and anesthetics.     

Occupational contact dermatitis in nurses with hand eczema

Occupationally related dermatitis is a common problem in nurses, who are exposed to a wide variety of allergenic and irritant substances. In a group of 44 nurses with hand dermatitis (40 female, 4 male), 18 were thought to have a predominantly allergic contact dermatitis, 15 an irritant dermatitis, 7 other form of eczema, 3 atopic dermatitis and one pompholyx. 10 of the 15 irritant cases were diagnosed as occupational. Of the 18 patients with allergic contact dermatitis, the allergens were thought to be occupationally relevant in 8 cases. In 6 of these 8 the dermatitis was due to natural rubber latex (3) or other rubber chemicals (3). 2 had additional evidence of immediate-type hypersensitivity to natural rubber latex (one was patch test allergic to latex, the other to thiuram mix). Natural rubber latex allergy, both delayed and immediate, is a significant problem, and nurses at risk should be tested for both types of hypersensitivity, as well as being patch tested to standard, rubber and medicaments series.     

LATE REACTION, PERSISTENT REACTION AND DOUBTFUL ALLERGIC REACTION: THE PROBLEMS OF INTERPRETATION

The standard method of patch test reading is to read the test site for any positive allergy at 48 hr and then again at 72/96 hr. A late reading on the seventh day is also advised to exclude the irritant reaction (IR) and to notice some delayed development of allergic reaction. However, multiple visits are often difficult for the patient; therefore, this late reading is sometimes omitted. Here a case of plantar hyperkeratosis, due to allergic contact dermatitis, is reported with some insight into interpretation of the patch test. The patient showed delayed patch test reaction to formaldehyde and colophony, which has never been reported before.     

Beneficial effects of a skin tolerance-tested moisturizing cream on the barrier function in experimentally-elicited irritant and allergic contact dermatitis

In experimentally-induced irritant (ICD) and allergic (ACD) contact dermatitis, an oil-in-water (o/w) cream was applied to investigate its effects on a disturbed barrier function compared to untreated physiological barrier repair. Transepidermal water loss (TEWL) measurements were performed. Before the start of the experiments, the skin tolerance of the cream was examined, revealing the non-irritating characteristics of the ingredients and the absence of any contact allergic patch test reaction. In the ICD study, sodium lauryl sulfate (SLS) patches were applied to the forearms of young female volunteers. Consequently, it was observed that repeated cream application (14 days, 2x/day) significantly improved the TEWL of SLS-damaged skin, leading to a complete recovery on day 15. In the ACD study, disruption of skin barrier function was obtained by a nickel-mediated contact allergy patch (CAP) test. The cream was then applied 2x/day for 4 consecutive days. Assessment of TEWL clearly showed that recovery of the disrupted skin significantly improved after cream application in comparison to untreated barrier repair.     

FS03.6Efficacy of MAS063D (''Atopiclair'') in irritant contact dermatitis

Objective:  To determine the efficacy of a topical, MAS063D, in managing the clinical signs and symptoms of experimentally induced irritant contact dermatitis (ICD).
Methods:  Two patches of ICD were created using sodium lauryl sulfate (SLS) in 20 consenting volunteers. MAS063D was applied to one patch and a vehicle‐only control to the other. Measurements were taken at baseline, 24, 48 and 72 hours as follows: blood flow volume (BFV); skin color (a*); transepidermal water loss (TEWL); patient's view of itch and visual scoring. Results: The objective measurements of BFV, a* and TEWL all showed statistically significant benefits of MAS063D over the vehicle‐only control. BFV and a* were significantly better at all time points (p = 0.046, p = 0.045 respectively at 72 hours) and TEWL at 48 and 72 hours (p = 0.02 at 72 hours). MAS063D demonstrated benefit in the visual scoring of irritant contact dermatitis that was not statistically significant. Patient‐assessed itch was low at baseline; significant improvement was neither expected nor demonstrated although a small benefit of MAS063D over vehicle was seen in the mean values.
Conclusions:  BFV and a* are both good indicators of local erythema. TEWL is a good indicator of skin integrity. MAS063D therefore demonstrated statistically significant benefit over vehicle on three clinically meaningful outcomes of SLS‐induced ICD, and therefore may benefit irritant contact dermatitis.     

Probable irritant contact dermatitis from phenylephrine in eyedrops with irritant (false-positive) phenylephrine patch test reactions

A 61-year-old white woman developed an acute eczema of the eyelids and periorbital region after application of eyedrops containing 10% phenylephrine hydrochloride (HCI) for an ophthalmologic examination. The patient showed false-positive (irritant) reactions both to eyedrops as is and phenylephrine HCI 10% aqueous after 48 hours, quickly fading at 72 hours, and unremarkable at 96 hours. There were false-positive results in 2 of 19 controls. Patch testing with phenylephrine HCI 1% aqueous, which is the correct testing concentration, was negative in both case patients and controls. Open tests showed a soaplike irritant effect only to 10% aqueous phenylephrine after 48 hours sharply marginated to the test site area. Repeated open application test further confirmed the above findings. Intradermal testing with phenylephrine showed no delayed reactions either in the affected patient or 19 controls. Irritant patch testing reactions do not necessarily indicate a diagnosis of irritant contact dermatitis; however, it is likely that in our patient, phenylephrine at its higher concentration (10%) was responsible for the clinical picture of irritant dermatitis.