Showing papers in "Contact Dermatitis in 2004"

Baboon syndrome resulting from systemic drugs: is there strife between SDRIFE and allergic contact dermatitis syndrome?

Abstract: The term 'baboon syndrome' (BS) was introduced 20 years ago to classify patients in whom a specific skin eruption resembling the red gluteal area of baboons occurred after systemic exposure to contact allergens. Thereafter, similar eruptions have been reported after systemic exposure to beta-lactam antibiotics and other drugs. In addition to the presentation of 2 of our own cases, we have reviewed and characterized the main clinical and histological aspects of published reports of drug-related baboon syndrome (DRBS) and compared the primary clinical signs from such cases to those found in other distinct drug eruptions. Of approximately 100 published baboon syndrome cases, 50 were identified as drug-induced. Of these, 8 were representatives of systemically induced contact dermatitis (SCD), and 42 were examples of drug eruptions elicited by systemic administration of either oral or intravenous drugs. The main clinical findings included a sharply defined symmetrical erythema of the gluteal area and in the flexural or intertriginous folds without any systemic symptoms and signs. 14 of 42 cases were elicited by amoxicillin, 30 of the 42 patients were male, and latency periods were between a few hours and a few days after exposure. DRBS is a rare, prognostically benign and often underdiagnosed drug eruption with distinct clinical features. The term baboon syndrome, however, does not reflect the complete range of symptoms and signs and is ethically and culturally problematic. Moreover, baboon syndrome is historically often equated with a mercury-induced exanthem in patients with previous contact sensitization. Symmetrical drug-related intertriginous and flexural exanthema, or SDRIFE, specifically refers to the distinctive clinical pattern of this drug eruption, and the following diagnostic criteria are proposed: 1) exposure to a systemically administered drug either at the first or repeated dose (excluding contact allergens); 2) sharply demarcated erythema of the gluteal/perianal area and/or V-shaped erythema of the inguinal/perigenital area; 3) involvement of at least one other intertriginous/flexural localization; 4) symmetry of affected areas; and 5) absence of systemic symptoms and signs.

Chlorhexidine anaphylaxis: case report and review of the literature

Abstract: Chlorhexidine is a widely used antiseptic and disinfectant. Compared to its ubiquitous use in medical and non-medical environments, the sensitization rate seems to be low. Multivarious hypersensitivity reactions to the agent have been reported, including delayed hypersensitivity reactions such as contact dermatitis, fixed drug eruptions and photosensitivity reactions. An increasing number of immediate-type allergies such as contact urticaria, occupational asthma and anaphylactic shock have been reported. In the case report, we describe anaphylaxis due to topical skin application of chlorhexidine, confirmed by skin testing and sulfidoleukotriene stimulation test (CAST(R): cellular antigen stimulation test). The potential risk of anaphylactic reactions due to the application of chlorhexidine is well known, especially that application to mucous membranes can cause anaphylactic reactions and was therefore discouraged. The use of chlorhexidine at a 0.05% concentration on wounds and intact skin was so far thought to be safe. Besides our patient, only one other case of severe anaphylactic reaction due to application of chlorhexidine on skin has been reported. Hypersensitivity to chlorhexidine is rare, but its potential to cause anaphylactic shock is probably underestimated. This review should remind all clinicians of an important potential risk of this widely used antiseptic.

Guidelines for the descriptive presentation and statistical analysis of contact allergy data

Abstract: The present guidelines aim to support clinical researchers in adequately presenting data on contact allergy, and to use statistical tests appropriate for their data. A description of the mode of selection of patients, and of their relevant demographic details, is an essential prerequisite for the correct interpretation of study results. Proportions and rates, if regarded as estimate of these parameters of a target populations, should normally be supplemented with confidence intervals to address precision. Concordance, i.e., agreement between two ratings in a dependent sample, must be quantified with a chance-corrected measure such as Cohen's kappa coefficient. If the diagnostic quality of an outcome is being assessed, standard measures like sensitivity and specificity, as well as the prevalence-dependent positive and negative predictive values should be calculated. Often, contact allergy to a certain substance depends on several factors. In this situation, depending on the research question, techniques like stratification, standardization or multifactorial analysis should be employed. With increasing complexity of statistical description and analysis, consulting with a biostatistician is often mandatory.

A survey of occupational hand eczema in Denmark.

Abstract: Occupational hand eczema (OHE) is the most frequently recognized work-related disease in Denmark and the annual cost to society is high. Understanding of the epidemiology of OHE is essential to be able to give appropriate recommendations for its prevention. The study comprised 758 persons, 490 females and 268 males with recognized OHE in the period October 2001 to November 2002. Data were obtained prospectively from the National Board of Industrial Industry Registry and from a self-administered questionnaire (response rate, 82%). The most frequently recognized diagnosis was irritant contact dermatitis (ICD), mainly caused by wet occupations. The proportion of occupational ICD was equal for males and females, 59.7% and 63.1%, respectively. The estimated rates of OHE were high for bakers, hairdressers and dental surgery assistants, and a high proportion of apprentices were found among hairdressers. The prevalence of atopic dermatitis was low (16.4%) compared to previous studies among hand eczema patients. The prevalence of occupational allergic contact dermatitis in the study population was substantially higher among males than females, and the most frequent causes among males were allergy to chromium (leather exposure), rubber additives (gloves) and nickel due to exposure from work tools and metalworking industry.

Contact allergy to fragrances: frequencies of sensitization from 1996 to 2002. Results of the IVDK*.

Abstract: Increasing frequencies of sensitization to the fragrance mix (FM) have been acknowledged as a serious problem for many years. It is well known that the single compounds (SCs) of the FM contribute differently to the FM patch rest reactions. In this study, we were interested in the time trends of the FM, the SCs, Myroxylon pereirae resin (MP; balsam of Peru) and oil of turpentine (OT) as possible further indicators of perfume allergy and analysed the data collected by the Information Network of Departments of Dermatology multicentre project from 1996 to 2002. During the study period (1996-2002), the FM [8% petrolatum (pet.)], MP (25% pet.) and OT (1% pet.) were tested in 59,298, 59,334 and 59,478 patients, respectively. SCs were tested in a selected group of patients, ranging from n = 1083 to n = 1924 per year. A significant increase in the proportions of patients with positive reactions to FM, MP and OT between 1996 and 1998 is noted, and a significant decline from 1999 to 2002 (Cochrane Armitage trend test, P < 0.0001). The highest frequency of sensitization to the FM was 13.1% in 1999, and the lowest 7.8% in 2002. The number of concomitant reactions to OT, a surrogate marker for terpenes, in FM-positive patients was significantly increased between 1997 and 1999. Reactions to SCs in FM-positive patients were observed in 29.9% (oak moss absolute) to 5.9% (geraniol). There was no time trend in reactions to SCs, although the relative share was increased for isoeugenol, cinnamic aldehyde and geraniol in 1999. In summary, we report for the first time, a significant decline in sensitization to the FM, very probably due to a reduced exposure (less potent allergens used in fine fragrances, possibly less use of natural ingredient-based cosmetics and lowered use concentration of important fragrance allergens). The differences in ranking of SCs could stimulate (a) a redefinition of the FM and (b) a differentiated preventive and regulatory approach, with oak moss and isoeugenol being regulated strictly by prohibition, concentration limits further reconsidered and/or health warnings and clearly less noxious substances like geraniol treated less restrictively.

A chemical dataset for evaluation of alternative approaches to skin-sensitization testing.

Abstract: Allergic contact dermatitis resulting from skin sensitization is a common occupational and environmental health problem. In recent years, the local lymph node assay (LLNA) has emerged as a practical option for assessing the skin-sensitization potential of chemicals. In addition to accurate identification of skin sensitizers, the LLNA can also provide a reliable measure of relative sensitization potency, information that is pivotal in successful management of human health risks. However, even with the significant animal welfare benefits provided by the LLNA, there is interest still in the development of non-animal test methods for skin sensitization. Here, we provide a dataset of chemicals that have been tested in the LLNA and the activity of which correspond with what is known of their potential to cause skin sensitization in humans. It is anticipated that this will be of value to other investigators in the evaluation and calibration of novel approaches to skin-sensitization testing. The materials that comprise this dataset encompass both the chemical and biological diversity of known chemical allergens and provide also examples of negative controls. It is hoped that this dataset will accelerate the development, evaluation and eventual validation of new approaches to skin-sensitization testing.

Frequency of contact allergy in German children and adolescents patch tested between 1995 and 2002: results from the Information Network of Departments of Dermatology and the German Contact Dermatitis Research Group.

Abstract: Allergic contact dermatitis (ACD) affects approximately 7% of the general population. To evaluate the frequency of ACD in children, we analysed patch test results collected by the Information Network of Departments of Dermatology between 1995 and 2002. Data of 285 children (6-12 year) and 2175 adolescent patients (13-18 year) were analysed to determine the frequency of sensitization to the 30 most common contact allergens, adjusting for age and sex. As control group, we defined adult patients (60-66 year, n = 7904). The top allergens in children were thimerosal, gentamicin sulphate, nickel-II-sulphate, ammoniated mercury, cobalt-II-chloride, fragrance mix, bufexamac, Compositae mix, propylene glycol and turpentine. The overall proportion of sensitized patients according to the patch test results was 52.6% in the children group compared to 49.7% in the adolescent group. These findings were similar in the adult group at 52.2%. The detailed analysis regarding sex, occupation, atopy, site of eczema and age showed distinct patterns in each group indicating age-specific exposures. Atopy-related diseases were more common in children compared to adults. On the basis of the data of this study, the relationship between atopy and the risk of development of ACD, at least in children, needs further investigation.

Ranking of hair dye substances according to predicted sensitization potency: quantitative structure–activity relationships

Abstract: Allergic contact dermatitis following the use of hair dyes is well known. Many chemicals are used in hair dyes and it is unlikely that all cases of hair dye allergy can be diagnosed by means of patch testing with p-phenylenediamine (PPD). The objectives of this study are to identify all hair dye substances registered in Europe and to provide their tonnage data. The sensitization potential of each substance was then estimated by using a quantitative structure-activity relationship (QSAR) model and the substances were ranked according to their predicted potency. A cluster analysis was performed in order to help select a number of chemically diverse hair dye substances that could be used in subsequent clinical work. Various information sources, including the Inventory of Cosmetics Ingredients, new regulations on cosmetics, data on total use and ChemId (the Chemical Search Input website provided by the National Library of Medicine), were used in order to identify the names and structures of the hair dyes. A QSAR model, developed with the help of experimental local lymph node assay data and topological sub-structural molecular descriptors (TOPS-MODE), was used in order to predict the likely sensitization potential. Predictions for sensitization potential were made for the 229 substances that could be identified by means of a chemical structure, the majority of these hair dyes (75%) being predicted to be strong/moderate sensitizers. Only 22% were predicted to be weak sensitizers and 3% were predicted to be extremely weak or non-sensitizing. Eight of the most widely used hair dye substances were predicted to be strong/moderate sensitizers, including PPD - which is the most commonly used hair dye allergy marker in patch testing. A cluster analysis by using TOPS-MODE descriptors as inputs helped us group the hair dye substances according to their chemical similarity. This would facilitate the selection of potential substances for clinical patch testing. A patch-test series with potent, frequently used, substances representing various chemical clusters is suggested. This may prove useful in diagnosing PPD-negative patients with symptoms of hair dye allergy and would provide some clinical validation of the QSAR predictions.

Determination of skin irritation potential in the human 4‐h patch test

Abstract: Recently adopted legislation in Europe has increased the focus that must be placed on the development of in vitro alternatives to the traditional toxicology tests employed to identify the human health hazards associated with chemicals. Included in these is the rabbit skin-irritation test which is used to discriminate those substances which possess significant acute skin irritation potential from those which are of more limited irritation potential. So far, the considerable efforts to replace this assay with in vitro alternatives have not been successful, which may in part be due to the relatively poor quality of the existing in vivo dataset. To help address this problem, we have elected to present our complete database of information on the skin irritation potential of some 65 substances, all of which have been tested in a standard human 4-h patch test. These provide a high quality dataset, generated in man (the goal of toxicologists' health protection-related activities). The data are presented in the context of results with a concurrent positive skin irritation control to ensure that results from individual experiments can be correlated. Consequently, in vitro or in silico alternatives which can identify the significant acute human skin irritants in this group may well represent suitable alternatives to the rabbit.

Low negative predictive value of skin tests in investigating delayed reactions to radio‐contrast media

Abstract: Delayed reactions to radio-contrast media (RCM) with positive skin tests are rare. We report the study of a series of 15 patients who presented delayed reactions to RCM, with an analysis of the clinical features and the results of standardized drug skin tests. Patch tests were performed with RCM and iodized antiseptics (IAs). If negative, prick tests were performed, followed by intradermal tests (IDTs), then intravenous administration under hospital surveillance. The main clinical features were maculopapular rashes or a macular rubella-like rashes. Patch tests were positive with RCM in 2 of 15 cases and with IAs in 4 of 15 cases. All the prick tests were negative. IDTs were positive at 24 h in 8 of 15 cases. 5 of 12 patients had a non-severe relapse of the rash upon receiving an RCM despite clearly negative skin tests with the readministered RCM. Visipaque cross-reacted with Iopamiron, Iomeron, Telebrix, Omnipaque, Xenetix and Hexabrix. Omnipaque cross-reacted with Hexabrix and Iopamiron. IDTs with delayed readings are of better value than patch tests in such patients. The readministration of RCM with negative IDTs must be performed with progressive amounts under hospital surveillance. Cross-reactions between various classes of RCM are frequent. The responsible epitopes are unknown. Iodine itself could be involved.

The vulvar epithelium differs from the skin: implications for cutaneous testing to address topical vulvar exposures.

Abstract: Vulvar tissue is more permeable than exposed skin due to differences in structure, occlusion, hydration and susceptibility to friction. The safety assessment of products that contact the vulva should account for this potentially heightened permeability. Standard clinical patch tests may not sufficiently mimic vulvar exposures. Because testing on the vulva is not routinely feasible, we are investigating new and modified cutaneous test methods to increase the degree of conservatism of the safety assessment. To this end, we have 1) developed a method to assess chemical and frictional effects by means of repeated application to the popliteal fossa (the behind-the-knee test); 2) modified the quantitative risk assessment for the induction of allergic contact dermatitis; and 3) proposed a modified human repeat insult patch test for assessing materials intended for vulvar contact. Modification of the traditional 4-day, irritation patch test by using wet samples or compromized skin sites failed to enhance test sensitivity. Future studies will evaluate testing in subjects with heightened susceptibility to chemical and sensory irritation, in order to increase test sensitivity to chemical irritants. These approaches can be employed to augment the margin of safety when cutaneous test methods are applied to agents that contact the vulva.

Strong irritants masquerading as skin allergens: the case of benzalkonium chloride.

Abstract: Chemicals may possess a number of hazards to human health including the ability to cause skin irritation and contact allergy. Identification and characterization of these properties should fall within predictive toxicology, but information derived from human exposure, including clinical experience, is also of importance. In this context, it is of interest to review the case of benzalkonium chloride, a cationic surfactant. This chemical is a well-known skin irritant, but on occasions it has also been reported to have allergenic properties, typically on the basis of positive diagnostic patch test data. Because the accumulated knowledge concerning the properties of a chemical is employed as the basis for its regulatory classification (e.g. in Europe), as well as for informing the clinical community with respect to the diagnosis of irritant versus allergic contact dermatitis (ACD), it is important to distinguish properly which chemicals are simply irritants from those which are both irritant and allergenic on skin. A review of the information on benzalkonium chloride confirms that it is a significant skin irritant. However, both predictive test results and clinical data lead to the conclusion that benzalkonium chloride is, at most, an extremely rare allergen, except perhaps in the eye, but with many supposed cases of ACD being likely to arise from the misinterpretation of patch test data. As a consequence, this substance should not normally be regarded as, or classified as, a significant skin sensitizer.

Patch test results with the metalworking fluid series of the German Contact Dermatitis Research Group (DKG).

Abstract: Based on the information of the interdisciplinary task force on allergy diagnostics in the metal branch, in 2001, the German Contact Dermatitis Research Group (DKG) compiled two metalworking fluid (MWF) test series with currently and previously used components, respectively. After 2 years of patch testing, we present results obtained with these series, based on data of the Information Network of Departments of Dermatology (IVDK). 251 metalworkers who were patch tested because of suspected MWF dermatitis in 2002 and 2003 were included in this retrospective data analysis. Of these, 206 were tested with the current MWF series and 155 with the historical MWF series. Among the current MWF allergens, monoethanolamine ranked 1st with 11.6% positive reactions. Diethanolamine (3.0%), triethanolamine (1.1%), and diglycolamine (1.9%) elicited positive reactions far less frequently. Allergic reactions to p-aminoazobenzene were frequently observed (6.0%), but the relevance of these reactions is still obscure. Positive reactions to biocides ranged from 4.5% for Bioban® CS 1135 to 0.5% for iodopropynyl butylcarbamate and 2-phenoxyethanol. Concomitant reactions to formaldehyde, which caused positive reactions in 3.3%, and formaldehyde releasers occurred to varying extents without conclusive pattern. No positive reactions were seen to dibutyl phthalate, di-2-ethylhexyl phthalate, tricresyl phosphate, isopropyl myristate or benzotriazole. With the historical MWF test series, positive reactions to methyldibromo glutaronitrile (MDBGN) were observed most frequently. However, sensitization via allergen sources other than MWF seems likely, as MDBGN, during the study period, has been one of the most frequent preservative allergens in cosmetics and body care products. Other historical MWF allergens comprised morpholinyl mercaptobenzothiazole (3.3%), benzisothiazolinone (BIT; 2.0%) and Bioban® P 1487(1.3%). BIT is currently used in MWF again, so it was shifted to the current MWF test series. As decreasing reaction frequencies to former MWF allergens that are no longer used can be expected, the historical series should be re-evaluated after some years. The test series with current MWF allergens has to be kept up-to-date based on information from industry and to be kept concise by eliminating test substances which never cause positive reactions.

Occupational skin diseases among dental nurses.

Abstract: Out of 923 female dental nurses in the Helsinki district, 799 were interviewed using a computer-assisted telephone interview. A structured questionnaire was used to inquire about skin, respiratory symptoms, atopy, work history and methods, and exposure at work. The 328 nurses, who reported work-related dermatitis on their hands, forearms or face, were invited to an interview by an occupational physician; 245 nurses participated. 31 nurses had previously been diagnosed with an occupational skin disease (OSD). 133 nurses with a suspected OSD were selected for further clinical examinations with prick and patch testing. Among the 107 nurses examined, 22 new cases of OSD were diagnosed. There were altogether 29 cases of allergic contact dermatitis, 15 of contact urticaria, 12 of irritant contact dermatitis, and 1 case of onychomycosis. Rubber chemicals and natural rubber latex (NRL) in protective gloves, as well as dental-restorative plastic materials [(meth)acrylates], were the most common causes of allergy. 42% of the OSD cases in the studied population had been missing from the statistics (Finnish Register of Occupational Diseases). Plastic gloves or NRL gloves with a low-protein content are recommended for dental work. Skin exposure to (meth)acrylates should be avoided.

Oral prednisone suppresses allergic but not irritant patch test reactions in individuals hypersensitive to nickel.

Abstract: A multicentre, randomized, double-blind, crossover study was designed to investigate the effects of prednisone on allergic and irritant patch test reactions. 24 subjects with known allergy to nickel were recruited and patch tested with a nickel sulfate dilution series in aqueous solution, 5% nickel sulfate in petrolatum and 2 dilution series of the irritants nonanoic acid and sodium lauryl sulfate. The subjects were tested x2, both during treatment with prednisone 20 mg oral daily and during placebo treatment. The total number of positive nickel patch test reactions decreased significantly in patients during prednisone treatment. The threshold concentration to elicit a patch test reaction increased and the overall degree of reactivity to nickel sulfate shifted towards weaker reactions. The effect of prednisone treatment on the response to irritants was divergent with both increased and decreased numbers of reactions, although there were no statistically significant differences compared with placebo. It is concluded that oral treatment with prednisone suppresses patch test reactivity to nickel, but not to the irritants tested.

Systemically induced allergic exanthem from mercury

Abstract: Cutaneous reactions to mercury can manifest themselves in different forms. Apart from contact dermatitis, flare-up reactions, disseminated exanthem as well as skin symptoms in previously unaffected skin are known. Regarding systemic allergen application, 2 separate clinical patterns, namely acute generalized exanthematous pustulosis (AGEP) and symmetric flexural exanthem 'baboon syndrome' have been described. Systemic allergic reactions to mercury are most commonly provoked by the inhalation of metallic mercury vapours from a broken thermometer, often after previous sensitization to mercury compounds, e.g. Mercurochrome. Patch testing with mercurials yields positive reactions in approximately 80% of patients. We report 3 patients, 2 with flexural exanthem, and 1 presenting with AGEP, respectively. Positive patch tests to mercury derivatives could be demonstrated in all of them. Furthermore, non-toxic serum mercury levels were detected in 2 of the patients. The present review provides a survey of the literature on systemic allergic exanthem to mercury. However, plausible explanations for the distribution pattern of the skin manifestations in AGEP and flexural exanthem are still lacking.

Exposure of the hands to wet work in nurses

Abstract: Prevention of hand dermatitis among nurses can be achieved by reduction of wet-work exposure. A preventive programme should be based on knowledge of exposure levels. An accurate method to assess such exposure levels is needed. Duration and frequency of wet-work activities were assessed by a questionnaire, in various parts of the health care sector. In addition, a randomly chosen sample from this population was observed for the duration and frequency of wet work. In contrast to the questionnaire, the observation method showed less than half the duration of wet work. Observation detected almost double the frequency that was reported with the questionnaire. Gloves were observed to be used daily in special care units for short time periods. A questionnaire does not accurately assess the quantity of wet-work activities. On regular wards, the exposure to irritants is mainly associated with the frequency of wet hands, rather than the duration of wet hands. We assume that the short-term use of gloves on special care units does not cause an increased risk of hand dermatitis. Preventive programmes can focus on decreasing the frequency of wet hands by encouraging the use of gloves; the use of gloves should not only be advised to prevent infections but also to protect against hand dermatitis.

Poor correlation between stated and found concentrations of diphenylmethane-4,4′-diisocyanate (4,4′-MDI) in petrolatum patch-test preparations

Abstract: Diphenylmethane diisocyanate (MDI) is widely used in its polymeric form in the manufacturing of polyurethane products. Previous reports on MDI-related contact allergy have shown a pattern, where patients seem to react to their own MDI-based work material but not to commercial patch-test preparations, which contain 4,4'-MDI. Therefore, we performed chemical analyses of 14 commercial test preparations of 4,4'-MDI obtained from 8 European and 4 American dermatology departments as well as 2 preparations from 2 major European suppliers of patch-test allergens. A new method for monitoring 4,4'-MDI in petrolatum preparations was developed and the determination of 4,4'-MDI as the MDI-dibutylamine derivative using liquid chromatography-mass spectrometry was performed. None of the preparations obtained from the dermatology departments contained more than 12% of the concentration stated on the label. In most cases, 4,4'-MDI content was only a few percentages or less of the concentration stated. 7 of the 14 preparations were analysed before the expiry date. Yet, only 1 of them, a preparation directly obtained from the supplier, came close to the concentration stated on the label. Thus, using these preparations, patients will be tested with a lower concentration than intended, leading to possible false-negative reactions.

Allergic and non-allergic periorbital dermatitis: patch test results of the Information Network of the Departments of Dermatology during a 5-year period.

Abstract: Periorbital dermatitis is common and can be due to the external use of ophthalmic drugs. We evaluated patch test results of the Information Network of the Departments of Dermatology. During a 5-year period (1995-99), of a total 49,256 patch-tested patients, 1053 (2.1%) were eventually diagnosed as allergic periorbital contact dermatitis (APD) and 588 (1.2%) as non-allergic periorbital dermatitis (NAPD). Patient characteristics between APD, NAPD and other cases (OCs) differed with respect to sex (19.7% male in both periorbital groups versus 36.3% in OCs), atopic dermatitis (10.4% in APD versus 60.2% in NAPD versus 16.9% in OCs) and age, APD being substantially more often (68.2%) aged 40 and above than NAPD (52.6%). Several of the top allergens in OCs [such as fragrance mix, Myroxylon pereirae resin (balsam of Peru), lanolin alcohol and potassium dichromate] caused significantly fewer positive test reactions in both periorbital groups. In contrast, thimerosal, phenylmercuric acetate, sodium disulfite, gentamicin sulfate, phenylephrine hydrochloride and benzalkonium chloride tested positively significantly more often in APD but not in NAPD, verifying them as true ophthalmic allergens. Finally, in 42 cases (4%) of APD patients, additional allergens were identified by testing of the patients' own substances (mostly beta-blockers, oxybuprocaine and dexpanthenol), supporting the necessity of testing with ophthalmic drugs as is where individual substances are not readily available.

The prognosis of occupational contact dermatitis in 2004

Abstract: The prognosis of occupational contact dermatitis (OCD) takes into account the extent of healing, effect on quality of life and employment, and financial costs for both the individual and the wider community. We reviewed 15 studies published between 1958 and 2002, reporting the complete clearance of dermatitis (range of 18-72%). 9 of the 15 studies reported a clearance rate of between 18 and 40%. Improvement was reported as an outcome in 3 studies between 1991 and 2002 (range of 70-84%). A number of common variables were identified as of possible influence. These include age, sex, atopy, patient knowledge, disease aetiology, duration of symptoms and job change; clinical, financial and social issues are also described. All of these factors need to be considered when managing a patient with OCD. Improved patient knowledge and early diagnosis may be associated with improved prognosis, whereas job change does not make a significant difference. Some patients will develop persistent post-occupational dermatitis, which has important implications for prognosis and workers' compensation. Only a small proportion of eligible patients receive workers' compensation, even though financially supported healing time soon after diagnosis may result in an improved prognosis.

Augmentation of skin response by exposure to a combination of allergens and irritants - a review.

Abstract: Clinical experimental studies on contact dermatitis (CD) often evaluate the effect of one allergen or one irritant at a time. In real life, the skin is often exposed to more allergens, more irritants or allergens and irritants in combination. This combined exposure may potentially influence irritant effects as well as allergenicity of the substances. Mechanisms for a changed response can be immunological effects or enhanced penetration. Knowledge about the influence on skin reaction of combined exposures may influence skin reactivity and is important for prevention of CD. For allergens, threshold values may be influenced by the presence of other allergens or irritants, and prevention of CD by regulation of threshold values may not be sufficient if this is not taken into account.

Further evaluation of quantitative structure--activity relationship models for the prediction of the skin sensitization potency of selected fragrance allergens

Abstract: Fragrance substances represent a very diverse group of chemicals; a proportion of them are associated with the ability to cause allergic reactions in the skin. Efforts to find substitute materials are hindered by the need to undertake animal testing for determining both skin sensitization hazard and potency. One strategy to avoid such testing is through an understanding of the relationships between chemical structure and skin sensitization, so-called structure-activity relationships. In recent work, we evaluated 2 groups of fragrance chemicals -- saturated aldehydes and alpha,beta-unsaturated aldehydes. Simple quantitative structure-activity relationship (QSAR) models relating the EC3 values [derived from the local lymph node assay (LLNA)] to physicochemical properties were developed for both sets of aldehydes. In the current study, we evaluated an additional group of carbonyl-containing compounds to test the predictive power of the developed QSARs and to extend their scope. The QSAR models were used to predict EC3 values of 10 newly selected compounds. Local lymph node assay data generated for these compounds demonstrated that the original QSARs were fairly accurate, but still required improvement. Development of these QSAR models has provided us with a better understanding of the potential mechanisms of action for aldehydes, and hence how to avoid or limit allergy. Knowledge generated from this work is being incorporated into new/improved rules for sensitization in the expert toxicity prediction system, deductive estimation of risk from existing knowledge (DEREK).

Occupational immunologic contact urticaria from pine processionary caterpillar (Thaumetopoea pityocampa): experience in 30 cases.

Abstract: Cutaneous lesions caused by the pine processionary caterpillar Thaumetopoea pityocampa (TP) are frequent in pinewood areas. In the present study, 30 patients diagnosed with occupational immunologic urticaria from this caterpillar were included. Immediate hypersensitivity was demonstrated by performing prick and IgE-immunoblotting tests. Workers were grouped according to their common tasks. Occupations at risk of exposure to TP were pine-cone collectors/woodcutters (14), farmers/stockbreeders (8), other forestry personnel (4), construction workers (2), residential gardeners (1) and entomologists (1). Besides contact urticaria, angioedema (60%), papular lesions of several days of evolution (30%) and anaphylactic reactions (40%) were also detected. The most frequently detected molecular weight bands by immunoblot were 15 (70%), 17 (57%) and 13 kDa (50%). The appearance of isolated bands corresponds with the least serious cases. Only 8 subjects had bands higher than 33 kDa, which was present in the 3 most severe cases of anaphylactic reactions. By presenting these cases, we wish to offer the largest series reported so far of occupational immunologic contact urticaria caused by TP. We include the first cases described in certain occupations, some of them not directly related to forestry work. Pine-cone or resin collectors, woodcutters, farmers and stockbreeders were the most frequently and severely affected workers.

Contact and photocontact allergy to ketoprofen. The Belgian experience.

Abstract: Topical ketoprofen (KP) is widely used because of its anti-inflammatory effect. However, photocontact dermatitis is a side-effect. Between May 2001 and June 2002, the Belgian Contact & Environmental Dermatitis Group conducted a prospective, open patch and photopatch test study in 20 patients suspected of KP dermatitis. Severe skin symptoms requiring systemic corticotherapy occurred in 47%. 5 patients were hospitalized. 1 patient showed prolonged photosensitivity. All patients were tested with KP and the other constituents of KP gel. Attribution to KP was demonstrated in all cases. Patch and photopatch tests with KP 2% in petrolatum showed contact photoallergy in 17 patients, contact allergy in 1 patient and photoaggravated contact allergy in 2 patients. 5 patients also reacted to the fragrance components lavender (Lavandula augustifolia) oil and/or neroli (Citrus aurantium dulcis) oil 5% in alcohol. However, in 4 of these, irritant reactions to the ethanolic dilutions could not be ruled out. Additional tests with 3 non-steroidal anti-inflammatory drugs without benzophenone structure ibuprofen, naproxen and diclofenac identified only 1 contact allergic reaction to diclofenac. Cross-reactivity to the substituted benzophenones, oxybenzone and sulisobenzone occurred only to the first in less than 30% of the patients. A high frequency (69%) of contact allergy to fragrance mix was found. Dermatologists should be aware of the severity of photoallergic reactions to KP and the risk of cross-sensitization.

The sex of the individual as a factor in allergic contact dermatitis.

Abstract: Exogenous and endogenous factors have been implicated in allergic contact dermatitis (ACD); this review explores the sex of the individual as a possible endogenous factor. While there is a clinical impression that women are more skin-reactive than men, upon review this hypothesis appears oversimplified. This review explores sex differences in controlled testing of adult ACD, occupational ACD and juvenile ACD. Further, geographical location and socioeconomic and cultural factors in relation to sex differences in allergic contact dermatitis are discussed. We conclude that female sex could be a factor predisposing to allergic contact dermatitis not so much because of possible differences in intrinsic skin characteristics between the sexes, but more because of different exposure patterns. This conclusion has practical consequences regarding product labelling requirements, occupational risk assessment and legislation.

Hair dye contact allergy: quantitative exposure assessment of selected products and clinical cases

Abstract: Colouring of hair can cause severe allergic contact dermatitis. The most frequently reported hair dye allergens are p-phenylenediamine (PPD) and toluene-2,5-diamine, which are included in, respectively, the patch test standard series and the hairdressers series. The aim of the present study was to identify dye precursors and couplers in hair dyeing products causing clinical hair dye dermatitis and to compare the data with the contents of these compounds in a randomly selected set of similar products. The patient material comprised 9 cases of characteristic clinical allergic hair dye reaction, where exposure history and patch testing had identified a specific hair dye product as the cause of the reaction. The 9 products used by the patients were subjected to chemical analysis. 8 hair dye products contained toluene-2,5-diamine (0.18 to 0.98%). PPD (0.27%) was found in 1 product, and m-aminophenol (0.015 to 0.38%) and p-aminophenol (0.16 to 2.1%) were found in 3 products. The concentration levels were similar in the patient's products compared to a random sample of 16 hair dye products. The concentration present of toluene-2,5-diamine elicited allergic reactions in concentrations that were 10-fold lower than the legal EU limit of 10%. Hair dye allergy may cause severe clinical reactions, and the current regulation is insufficient in protection of the users. A preventive strategy is needed.

Reproducibility of patch test results: a concurrent right‐versus‐left study using TRUE Test™

Abstract: Wide variations in the reproducibility rate of positive patch test responses have been reported. We hypothesized that a major source of non-reproducibility resides in the methodological pitfalls of routine patch testing. Simultaneous duplicate patch testing on opposite sides of the upper back was performed on 500 consecutive patients, using the TRUE Test system consisting of 2 panels, each one containing 12 standard allergens. A rigorous methodological design was applied and relevance was assessed for all discordant patch test reactions. A total of 435 positive patch test reactions were observed either on one or both sides in 289 patients (58.8%). Of these, 22 (5%) were discordant, i.e. interpreted as positive allergic on one side whilst negative or doubtful on the opposite side. The allergens responsible for discordant reactions were nickel sulfate (4 patients), cobalt chloride (3), lanolin alcohol (3), fragrance mix (2), carba mix (2), thiuram mix (2), colophonium (1), potassium dichromate (1), p-phenylenediamine (1), formaldehyde (1), balsam of Peru (Myroxylon pereirae resin) (1) and thimerosal (1). Of the 19 (4%) patients with discordant patch test reactions, the allergen was deemed to be of definite present or past relevance in 9 patients (1.8% of the total and 3.1% of all patients with positive patch test reactions) and of possible relevance in a further 2 patients. These data suggest that patch testing is a reasonably reproducible procedure as long as methodological error is minimized.

Methacrylates in dental restorative materials.

Abstract: Commercial dental restorative materials were analysed in order to obtain information about the occurrence of sensitizing acrylates. Acetone-soluble methacrylates of 7 bonding materials, 8 composite resins and 2 glass ionomers were identified by gas chromatography with mass-selective detection and quantified by liquid chromatography with ultraviolet detection. The most frequently occurring methacrylates in the bonding materials were 2-hydroxyethyl methacrylate (2-HEMA) and 2,2-bis-[4-(2-hydroxy-3-methacryloxypropoxy)phenyl]-propane (bis-GMA). Bis-GMA and triethyleneglycol dimethacrylate were the most frequently occurring methacrylates in composite resins. The main methacrylate of the 2 glass ionomers was 2-HEMA or trimethylolpropane trimethacrylate. Information about methacrylates was given in the safety data sheets (SDSs) for about half of the products that according to the analysis results contained methacrylates. SDSs need to be improved so that the health risks for dental personnel can be reliably assessed and controlled.

Skin protection in nursing work: promoting the use of gloves and hand alcohol

Abstract: Nursing has been identified as a wet-work occupation, with a high prevalence of occupational irritant contact dermatitis. Reduction of exposure to skin irritants contributes to the prevention of occupational skin disease in nurses. The role of the use of soap and water, hand alcohol and gloves in prevention programmes is discussed. 2 additional measures for reducing exposure to skin irritants are postulated: use of hand alcohol instead of soap and water in disinfection procedures when the hands are not visibly dirty; use of gloves in wet activities such as patient washing to prevent the hands from becoming wet and visibly dirty. We investigated the effectiveness of these recommendations in a model. Mean daily wet-work exposure during nursing work was modelled: regular model. We also modelled exposure to skin irritants in combination with the implementation of these recommendations: prevention model. The hands of healthy volunteers were exposed to the regular or the prevention model over 3 weeks for 5 days a week. The change in transepidermal water loss (TEWL) on the back of the hands was measured after 3 weeks of exposure to these wet-work simulations. An increase in TEWL occurred with the regular model, while mean TEWL decreased in the prevention model. Skin irritation from occlusion by gloves appeared to be more pronounced in the regular model compared to the prevention model. The results of this study justify the conclusion that in nursing work, hand alcohol is the preferred disinfectant. Although the prevention model implies increased occlusive exposure, this has no additional irritant effect, probably because of the absence of soap exposure.

A study of cross-reactions between mango contact allergens and urushiol.

Abstract: The allergens causing mango dermatitis have long been suspected to be alk(en)yl catechols and/or alk(en)yl resorcinols on the basis of observed cross-sensitivity reactions to mango in patients known to be sensitive to poison ivy and oak (Toxicodendron spp.). Earlier, we reported the 3 resorcinol derivatives: heptadecadienylresorcinol (I), heptadecenylresorcinol (II) and pentadecylresorcinol (III); collectively named 'mangol', as mango allergens. In this study, we extracted the 1st 2 components (I and II) from the Philippine mango, adjusted them to 0.05% concentration in petrolatum and patch tested the components on 2 subjects with mango dermatitis. Both subjects reacted to I. 1 subject also elicited a weaker positive reaction to II. To investigate the cross-reaction between mangol and urushiol, we also patch tested the same subjects with urushiol. The subject sensitive to II reacted to urushiol. 6 subjects with a history of lacquer contact dermatitis and positive reactions to urushiol were similarly patch tested. 5 persons reacted to I. 2 subjects also exhibited a slower but positive reaction to II. This is the 1st report in which heptadec(adi)enyl resorcinols known to be present in mango have been shown to elicit positive patch test reactions in mango-sensitive patients.