Contact-Allergic Reactions to Cosmetics

Contact-allergic reactions to cosmetics may be delayed-type reactions such as allergic and photo-allergic contact dermatitis, and more exceptionally also immediate-type reactions, that is, contact urticaria. Fragrances and preservative agents are the most important contact allergens, but reactions also occur to category-specific products such as hair dyes and other hair-care products, nail cosmetics, sunscreens, as well as to antioxidants, vehicles, emulsifiers, and, in fact, any possible cosmetic ingredient. Patch and prick testing to detect the respective culprits remains the golden standard for diagnosis, although additional tests might be useful as well. Once the specific allergens are identified, the patients should be informed of which products can be safely used in the future

ALERGIA CUTÂNEA EM CRIANÇAS

As with adults, the history and localization of the dermatitis are crucial for the diagnosis of allergic contact dermatitis, certain contactants and/or habits that are characteristic for the child/adolescent may be responsible for unu- sual clinical presentations. The most important allergens in children are metals, such as chromium (in shoes) and nickel (sometimes associated with cobalt or palladium, the latter also giving rise to contact granulomas), particularly in girls, due to the popularity of cheap jewellery. More recently, other sources, like cell phones, emerged among young adults. Other allergens identified are ingredients of topical pharmaceutical products, particularly antiseptic agents; mercury and its derivatives are still used in some countries, but allergic reactions, even in young children, are most often not cli- nically relevant. Cosmetics, particularly skin care products and wipes, may give rise to sensitization to fragrance compo- nents or preservative agents. Rubber derivatives, often responsible for shoe or diaper dermatitis, resins, and plants may also be among the sensitization sources involved. Moreover, certain occupational allergens (e.g., those associated with hairdressing, construction, and metalworking) are found in adolescents. Changing regulations concerning the presence of allergens in common products, the incidence of contact allergy in children might decrease in the future (e.g. nickel in jewellery and mobile phones and hair dyes in children below the age of 16 years). The use of p-phenylenediamine in temporary henna tattoos still remains a problem. Patch testing in children is safe; most authors consider that irritant reactions are not frequently observed (except in atopics, particularly with metals) and the same patch test concentra- tions as in adults can be used. However, the possibility of false-positive and false-negative reactions has to be consi- dered and, if there is doubt about irritancy, lower patch test concentrations should also be tested. Due to reduced test surface area, diminished environmental exposure to certain allergens and particularly hypermobility of young children, testing with an abbreviated standard series is recommended by some, although others warn that many reactions may thus be missed. Anyway, it is important to take into account the history and clinical picture and to always add possible other allergens and personal products used.KEYWORDS – Dermatitis; Allergic Contact; Child; Allergens; Hypersensitivity.No diagnóstico de dermatite de contacto alérgica é fundamental, tal como nos adultos, a história e loca- lização das lesões, mas alguns produtos e/ou hábitos característicos das crianças e adolescentes podem ser respon- sáveis por quadros clínicos pouco usuais. Os alergenos mais importantes na criança são os metais, como o crómio (calçado) e o níquel (por vezes associado ao cobalto ou paládio; este último também responsável por reacções gra- nulomatosas de contacto), sobretudo nas jovens, dada a popularidade dos adornos baratos. Recentemente, surgiram entre os jovens outras fontes de sensibilização, como os telemóveis. Outros potenciais alergenos são os ingredientes de produtos tópicos, sobretudo antissépticos; o mercúrio e derivados ainda são utilizados nalguns países, mas as re- acções alérgicas, mesmo em crianças pequenas, não são em geral clinicamente relevantes. Cosméticos, em particular de limpeza cutânea, podem originar sensibilização a componentes das fragrâncias ou conservantes. Derivados da borracha, muitas vezes responsáveis por dermatite ao calçado ou às fraldas, resinas e plantas também podem ser fonte de sensibilização. Adicionalmente, alguns alergenos ocupacionais (p. ex, cabeleireiras, construção civil e me- talúrgicos) também ocorrem em adolescentes. A alteração da legislação, referente à presença de alergenos em pro- dutos comuns, pode levar à redução da incidência de alergia de contacto em crianças (p. ex, ao níquel nos adornos e telemóveis e às tintas capilares em menores de 16 anos). O uso de p-fenilenodiamina nas tatuagens temporárias de henna continua a ser um problema. As provas epicutâneas em crianças são seguras; a maioria dos autores con- sideram as reacções irritativas pouco frequentes (excepto em atópicos, em particular a metais) e podem utilizar-se as mesmas concentrações que no adulto. No entanto, não se pode excluir a possibilidade de reacções falso+ ou falso- e, na suspeita de potencial irritativo, devem também testar-se concentrações inferiores. Dada a reduzida área cutânea para testes, a menor exposição ambiental a alguns alergenos e a hipermobilidade das crianças pequenas, alguns autores recomendam utilizar séries standard reduzidas, embora outros alertem para o risco de se ignorarem muitas reacções. De qualquer modo, é importante ter em conta a história e o quadro clínico e testar, sempre que necessário, outros possíveis alergenos e produtos pessoais.PALAVRAS-CHAVE – Dermatite; Alergia de Contacto; Criança; Alergenos; Hipersensibilidade

Patch and Photo-Patch Testing are Important in Patients with Idiopathic Photodermatoses

This number of the Revista da Sociedade Portuguesa de Dermatologia e Venereologia contains two articles dedicated to idiopathic photodermatoses, for which autoimmune reactions to an unknown endogenous chromophore are suspected to be involved – polymorphous light eruption, actinic prurigo, hydroa vacciniforme, chronic actinic dermatitis, and solar urticarial.1,2 Many of these and other photodermatoses have a very clear clinical presentation, while others may mimic allergic contact dermatitis (ACD) or photo-allergic contact dermatitis (PhACD), a classical T cell-mediated or delayed type IV hypersensitivity reaction to an exogenous chromophore applied on the skin in the presence of, or followed by exposure to ultraviolet (UV) or visible light.3,4 Allergic contact reactions can be followed by persistent photosensitivity and chronic actinic dermatitis, such as in cases of chronic ACD from certain plants, e.g., Compositae that are rich in sesquiterpene lactones,5 fragrances, lichens, and colophony,4 or in PhACD or photo-aggravated ACD from drugs like ketoprofen, etofenamate, and chlorproethazine, or even other contact allergens, such as tosylamide/formaldehyde resin, fragrances, and thiourea derivatives.4The long persistence of these chemicals in the epidermis (for up to at least 17 days in the case of ketoprofen),6 or the formation of endogenous photosensitizers might perhaps explain the progression to chronic actinic dermatitis.4In patients with idiopathic photodermatoses the use of sunscreens is mandatory, however, the sensitization risk from these chemicals may be enhanced by the previous skin inflammation and the need for repeated application for long periods.7 UV filters, which are chromophores that capture UV light, are among the most frequent causes of PhACD,8-11 namely benzophenones, dibenzoylmethane derivatives, octocrylene, and cinammates.9,10,12-14 Although more recent UV filters seem to be more photostable and less prone to induce PhACD,3 a few cases have been described,9 for example, from polysilicone-15 (Parsol®SLX).15 With regard to methylene bis-benzotriazolyl tetramethylbutylphenol (syn. bisoctrizole or Tinosorb® M), ACD from it is due to the surfactant decyl glucoside, in particular, which is added in order to stabilize the sunscreen molecule.16,17Topical drugs, such as the non-steroidal anti-inflammatory ketoprofen, piketoprofen, suprofen, etofenamate, piroxicam, and benzydamine,18 as well as phenothiazine derivatives, i.e., promethazine or chlorproethazine, and isothipendyl chlorhydrate19 are frequent causes of ACD/PhACD, either by direct application or by transfer from other individuals in close contact (consort or connubial dermatitis). Moreover, some of these chemicals, particularly ketoprofen, exhibit cross-reactions with UV filters, i.e., benzophenone(s) and octocrylene, the latter containing benzophenone residues. Also fenofibrate, a systemic drug, shares the benzophenone ring and can cross react with ketoprofen and related molecules.3,20 Furthermore, patients with PhACD from ketoprofen present with concomitant reactions to the perfume ingredient cinnamic alcohol, reactions that at present are difficult to explain by cross-reactivity.21Therefore, patch and photo-patch testing are highly recommended in patients with idiopathic and autoimmune photodermatoses, as well as in all other diseases aggravated by sunlight, in order to detect and avoid exposure to possible aggravating factors, and particularly to UV filters. Recently, recommendations for diagnostic patch testing have been issued by the European Society of Contact Dermatitis (ESCD),22 and in a cooperative effort of the ESCD and European Society of Photodermatology (ESPD), an agreement was not only reached regarding standardized protocols for photo-patch testing,23 but also on the list of 20 allergens to be included in the European baseline photo-patch tests series and an additional extended series including certain classical photo-allergens.24 Last but not least, photo-patch tests with all the patient’s own topical products and systemic photosensitizers to which the patients is exposed are strongly recommended as well, since the outcome may further contribute to the relevance of positive reactions observed, or avoid “false”- negative reactions obtained by testing standardized allergens only.24This number of the Revista da Sociedade Portuguesa de Dermatologia e Venereologia contains two articles dedicated to idiopathic photodermatoses, for which autoimmune reactions to an unknown endogenous chromophore are suspected to be involved – polymorphous light eruption, actinic prurigo, hydroa vacciniforme, chronic actinic dermatitis, and solar urticarial.1,2 Many of these and other photodermatoses have a very clear clinical presentation, while others may mimic allergic contact dermatitis (ACD) or photo-allergic contact dermatitis (PhACD), a classical T cell-mediated or delayed type IV hypersensitivity reaction to an exogenous chromophore applied on the skin in the presence of, or followed by exposure to ultraviolet (UV) or visible light.3,4 Allergic contact reactions can be followed by persistent photosensitivity and chronic actinic dermatitis, such as in cases of chronic ACD from certain plants, e.g., Compositae that are rich in sesquiterpene lactones,5 fragrances, lichens, and colophony,4 or in PhACD or photo-aggravated ACD from drugs like ketoprofen, etofenamate, and chlorproethazine, or even other contact allergens, such as tosylamide/formaldehyde resin, fragrances, and thiourea derivatives.4The long persistence of these chemicals in the epidermis (for up to at least 17 days in the case of ketoprofen),6 or the formation of endogenous photosensitizers might perhaps explain the progression to chronic actinic dermatitis.4In patients with idiopathic photodermatoses the use of sunscreens is mandatory, however, the sensitization risk from these chemicals may be enhanced by the previous skin inflammation and the need for repeated application for long periods.7 UV filters, which are chromophores that capture UV light, are among the most frequent causes of PhACD,8-11 namely benzophenones, dibenzoylmethane derivatives, octocrylene, and cinammates.9,10,12-14 Although more recent UV filters seem to be more photostable and less prone to induce PhACD,3 a few cases have been described,9 for example, from polysilicone-15 (Parsol®SLX).15 With regard to methylene bis-benzotriazolyl tetramethylbutylphenol (syn. bisoctrizole or Tinosorb® M), ACD from it is due to the surfactant decyl glucoside, in particular, which is added in order to stabilize the sunscreen molecule.16,17Topical drugs, such as the non-steroidal anti-inflammatory ketoprofen, piketoprofen, suprofen, etofenamate, piroxicam, and benzydamine,18 as well as phenothiazine derivatives, i.e., promethazine or chlorproethazine, and isothipendyl chlorhydrate19 are frequent causes of ACD/PhACD, either by direct application or by transfer from other individuals in close contact (consort or connubial dermatitis). Moreover, some of these chemicals, particularly ketoprofen, exhibit cross-reactions with UV filters, i.e., benzophenone(s) and octocrylene, the latter containing benzophenone residues. Also fenofibrate, a systemic drug, shares the benzophenone ring and can cross react with ketoprofen and related molecules.3,20 Furthermore, patients with PhACD from ketoprofen present with concomitant reactions to the perfume ingredient cinnamic alcohol, reactions that at present are difficult to explain by cross-reactivity.21Therefore, patch and photo-patch testing are highly recommended in patients with idiopathic and autoimmune photodermatoses, as well as in all other diseases aggravated by sunlight, in order to detect and avoid exposure to possible aggravating factors, and particularly to UV filters. Recently, recommendations for diagnostic patch testing have been issued by the European Society of Contact Dermatitis (ESCD),22 and in a cooperative effort of the ESCD and European Society of Photodermatology (ESPD), an agreement was not only reached regarding standardized protocols for photo-patch testing,23 but also on the list of 20 allergens to be included in the European baseline photo-patch tests series and an additional extended series including certain classical photo-allergens.24 Last but not least, photo-patch tests with all the patient’s own topical products and systemic photosensitizers to which the patients is exposed are strongly recommended as well, since the outcome may further contribute to the relevance of positive reactions observed, or avoid “false”- negative reactions obtained by testing standardized allergens only.2

In vivo and In vitro Interactions between Pseudomonas aeruginosa and Staphylococcus spp.

The significance of polymicrobial infections is increasingly being recognized especially in a biofilm context wherein multiple bacterial species—including both potential pathogens and members of the commensal flora—communicate, cooperate, and compete with each other. Two important bacterial pathogens that have developed a complex network of evasion, counter-inhibition, and subjugation in their battle for space and nutrients are Pseudomonas aeruginosa and Staphylococcus aureus. Their strain- and environment-specific interactions, for instance in the cystic fibrosis lung or in wound infections, show severe competition that is generally linked to worse patient outcomes. For instance, the extracellular factors secreted by P. aeruginosa have been shown to subjugate S. aureus to persist as small colony variants (SCVs). On the other hand, data also exist where S. aureus inhibits biofilm formation by P. aeruginosa but also protects the pathogen by inhibiting its phagocytosis. Interestingly, such interspecies interactions differ between the planktonic and biofilm phenotype, with the extracellular matrix components of the latter likely being a key, and largely underexplored, influence. This review attempts to understand the complex relationship between P. aeruginosa and Staphylococcus spp., focusing on S. aureus, that not only is interesting from the bacterial evolution point of view, but also has important consequences for our understanding of the disease pathogenesis for better patient management

Patch Testing with a Textile Dye Mix in a Baseline Series in Two Countries

Disperse dyes are the most common contact sensitizers among textile dyes. The main aim of this study was to investigate the outcome of patch testing with a textile dye mix 6.6%. A total of 2,049 patients from Sweden and 497 from Belgium were tested with the mix, consisting of Disperse (D) Blue 35, D Yellow 3, D Orange 1 and 3, D Red 1 and 17, 1.0% each, and D Blue 106 and D Blue 124, 0.3% each. Of the total number, 65 patients, 2.6%, tested positively to the mix, 4.2% of the Belgian patients and 2.1% of the Swedish patients. Patch testing with the mix 6.6% revealed significantly more patients with contact allergy compared with testing with a previous mix 3.2% (p<0.01). Contact allergy to the mix was significantly more common in the Belgian than in the Swedish patients

Incidental chest radiographic findings in adult patients with acute cough

PURPOSE Imaging may produce unexpected or incidental findings with consequences for patients and ordering of future investigations. Chest radiography in patients with acute cough is among the most common reasons for imaging in primary care, but data on associated incidental findings are lacking. We set out to describe the type and prevalence of incidental chest radiography findings in primary care patients with acute cough. METHODS We report on data from a cross-sectional study in 16 European primary care networks on 3,105 patients with acute cough, all of whom were undergoing chest radiography as part of a research study workup. Apart from assessment for specified signs of pneumonia and acute bronchitis, local radiologists were asked to evaluate any additional finding on the radiographs. For the 2,823 participants with good-quality chest radiographs, these findings were categorized according to clinical relevance based on previous research evidence and analyzed for type and prevalence by network, sex, age, and smoking status. RESULTS Incidental findings were reported in 19% of all participants, and ranged from 0% to 25% by primary care network, with the network being an independent contributor (P < .001). Of all participants 3% had clinically relevant incidental findings. Suspected nodules and shadows were reported in 1.8%. Incidental findings were more common is older participants and smokers (P < .001). CONCLUSIONS Clinically relevant incidental findings on chest radiographs in primary care adult patients with acute cough are uncommon, and prevalence varies by setting

Three Dimensional MHD Wave Propagation and Conversion to Alfven Waves near the Solar Surface. I. Direct Numerical Solution

The efficacy of fast/slow MHD mode conversion in the surface layers of sunspots has been demonstrated over recent years using a number of modelling techniques, including ray theory, perturbation theory, differential eigensystem analysis, and direct numerical simulation. These show that significant energy may be transferred between the fast and slow modes in the neighbourhood of the equipartition layer where the Alfven and sound speeds coincide. However, most of the models so far have been two dimensional. In three dimensions the Alfven wave may couple to the magneto-acoustic waves with important implications for energy loss from helioseismic modes and for oscillations in the atmosphere above the spot. In this paper, we carry out a numerical ``scattering experiment'', placing an acoustic driver 4 Mm below the solar surface and monitoring the acoustic and Alfvenic wave energy flux high in an isothermal atmosphere placed above it. These calculations indeed show that energy conversion to upward travelling Alfven waves can be substantial, in many cases exceeding loss to slow (acoustic) waves. Typically, at penumbral magnetic field strengths, the strongest Alfven fluxes are produced when the field is inclined 30-40 degrees from the vertical, with the vertical plane of wave propagation offset from the vertical plane containing field lines by some 60-80 degrees.Comment: Accepted for the HELAS II/ SOHO 19/ GONG 2007 Topical Issue of Solar Physic