Search

Background: Metals are common agents of allergic contact dermatitis, occupational or not, with decreasing incidence over the last years in some countries that have regulated the amount of nickel in objects. Objectives: To analyze and compare with previous studies the profile of metal sensitization between 2003-2015. Methods: Patients who underwent patch testing between 2003-2015 were evaluated retrospectively regarding the sensitization rates to metals, the associations between them, the relationship with profession and epidemiology. Results: Of the 1,386 patients tested, 438 (32%) had positive test to some metal, similar results to the 404/1,208 (33%) of the previous study (1995-2002) performed at the same service (p=0.32). The frequency of nickel (77%), cobalt (32%) and chromium (29%) changed slightly (p=0.20). Most cases of sensitization to chromium were related to the occupation (64%), in contrast to nickel and cobalt (p

FUNDAMENTOS: A dermatite de contato e uma das dermatoses comumente relacionadas ao trabalho. Entre os pedreiros o cimento pode causar tanto a Dermatite Alergica de Contato quanto a Dermatite de Contato por Irritacao Primaria. Os equipamentos de protecao individual (luvas de borracha) podem favorecer o desenvolvimento de Dermatite Alergica de Contato. OBJETIVOS: 1) avaliar a frequencia de Dermatite Alergica de Contato entre os pedreiros entre Janeiro de 2005 e Dezembro de 2009; 2) determinar os principais agentes sensibilizantes; e 3) comparar os resultados obtidos entre o grupo de pedreiros com um grupo sem pedreiros. METODOS: analise retrospectiva de testes de contato. Pacientes foram separados em 2 grupos: 1) pedreiros e 2) nao pedreiros. RESULTADOS: dentre os 525 testes de contato analisados, 466 (90%) eram de nao pedreiros e 53 (10%) de pedreiros. As maos foram acometidas em 38 (61%). 13 pacientes (24%) tinham Dermatite de Contato por Irritacao Primaria e 40 (76%) tinham Dermatite Alergica de Contato. O grupo de pedreiros apresentou alta frequencia de sensibilizacao ao cimento, e 29 (54,7%) tinham sensibilizacao a agentes vulcanizadores da borracha. 23 pacientes (43,4%) pedreiros tinham sensibilizacao tanto ao cimento quanto a borracha. CONCLUSOES: entre os pedreiros a presenca de Dermatite Alergica de Contato ao cimento e a borracha no mesmo paciente foi comum e demonstrou a importância do teste de contato.

BACKGROUND: Scleroderma is a chronic autoimmune disease characterized by progressive connective tissue sclerosis and microcirculatory changes. Localized scleroderma is considered a limited disease. However, in some cases atrophic and deforming lesions may be observed that hinder the normal development. Literature reports indicate phototherapy as a therapeutic modality with favorable response in cutaneous forms of scleroderma. OBJECTIVES: This study had the purpose of assessing the phototherapy treatment for localized scleroderma. METHODS: Patients with localized scleroderma were selected for phototherapy treatment. They were classified according to the type of localized scleroderma and evolutive stage of the lesions. Clinical examination and skin ultrasound were used to demonstrate the results thus obtained. RESULTS: Some clinical improvement was observed after an average of 10 phototherapeutic sessions. All skin lesions were softer at clinical palpation with scores reduction upon pre and post treatment comparison. The ultrasound showed that most of the assessed lesions presented a decrease in dermal thickness, and only five maintained their previous measure. Treatment response was similar regardless of the type of phototherapeutic treatment employed. CONCLUSIONS: The proposed treatment was effective for all lesions, regardless of the phototherapeutic modality employed. The improvement was observed in all treated skin lesions and confirmed by clinical evaluation and skin ultrasound. FUNDAMENTOS: A esclerodermia é uma doença autoimune caracterizada pela esclerose progressiva do tecido conjuntivo e alterações da microcirculação. A forma cutânea é considerada uma doença autolimitada. No entanto, em alguns casos, ocorrem lesões atróficas, deformantes, que dificultam o desenvolvimento normal. Relatos da literatura apontam a fototerapia como uma modalidade terapêutica com resposta favorável nas formas cutâneas da esclerodermia. OBJETIVOS: Este trabalho teve como objetivo avaliar o tratamento da esclerodermia cutânea com fototerapia. MÉTODOS: Foram selecionados pacientes com diagnóstico de esclerodermia cutânea para o tratamento com fototerapia, os quais foram classificados de acordo com o tipo clínico e o estágio evolutivo das lesões. Utilizou-se o exame clínico e a ultrassonografia da pele como metodologia para demonstrar os resultados obtidos com o tratamento proposto. RESULTADOS: Foi observado o início da melhora clínica das lesões com média de 10 sessões de fototerapia. A palpação clínica mostrou amolecimento em todas as lesões estudadas, com redução nos escores de avaliação estabelecidos. No exame de ultrassom, a maioria das lesões avaliadas mostrou diminuição da espessura da derme, e apenas cinco mantiveram sua medida. Não se observou diferença na resposta ao tratamento de acordo com o tipo de fototerapia instituída. CONCLUSÕES: O tratamento proposto foi efetivo em todas as lesões, independentemente do tipo de fototerapia realizada. A melhora foi observada em todas as lesões tratadas e comprovada pela avaliação clínica e pelo exame de ultrassom da pele.

BACKGROUND Moderate and severe forms of psoriasis require phototherapy and / or systemic medications. Both UVA and UVB can be used to treat cases of moderate and severe psoriasis, and the effectiveness of both has been proven. OBJECTIVE to access the prescription behavior relating to two types of phototherapy for treating psoriasis refractory to topical treatment: narrowband UVB (NB-UVB) or psoralen plus UVA phototherapy (PUVA). METHODS Between January 2006 and December 2007, patients referred to two phototherapy services were included in this study. Data on the cases and on the type of prescription were collected retrospectively. RESULTS Among the 67 studied patients, 51 (76%) were treated with narrowband UVB. The reasons for the indication were the presence of the guttate type of psoriasis (22%), the presence of thin plaques (15%), the use of drugs that affected photosensitivity (15%), age less than 20 years (9%), skin type I (9%), and liver disease (6%). The remaining 16 (24%) were treated with PUVA. The main indication for this therapy was the severity of the disease (15%), followed by the presence of skin type IV (9%). CONCLUSIONS Prescriptions of narrowband UVB exceeded those of PUVA because of fewer contraindications and fewer possible side effects, and because it was a more practical option.

FUNDAMENTOS - Tacrolimo pomada é eficaz no tratamento da dermatite atópica. OBJETIVOS - Avaliar a eficácia e segurança do tacrolimo pomada 0,03% (Protopic®) no tratamento de pacientes pediátricos com dermatite atópica. MÉTODOS - Estudo multicêntrico, aberto e não comparativo. Incluídos 174 pacientes (dois a 10 anos)com dermatite atópica. Utilizou-se tacrolimo duas vezes ao dia, por seis semanas. O critério primário de eficácia foi a melhora clínica > a 90% avaliada pelo médico (Escala de Avaliação Global da Resposta Clínica). Outros critérios de eficácia foram a redução no índice de área e gravidade do eczema (EASI), a redução do percentual de superfície corporal afetada (%BSA) e a avaliação do prurido pelo paciente (escala analógica visual). Segurança foi avaliada pela ocorrência de eventos adversos relatados pelos pais e pacientes ou pelos investigadores. RESULTADOS - Trinta e três por cento dos pacientes apresentaram melhora clínica >90%. Quando avaliado o escore EASI, houve redução de 45,5% (primeira semana) e 61,8% (sexta semana) quando comparado com o basal (p

BACKGROUND Liquid nail varnish has been used since 1919, and allergic contact dermatitis (ACD) has been recognized for at least 80 years, but it is difficult for nonspecialists to identify this condition. OBJECTIVES (1) To verify the frequency of ACD from nail varnish in patients with a presumptive diagnosis of contact dermatitis seen at an outpatient clinic, (2) to characterize the groups studied according to site of skin disorder, and (3) to determine the main sensitizer related to varnish. METHODS Patients with a final diagnosis of ACD caused by nail varnish were assessed by means of retrospective analysis of medical charts and protocols used in the clinic from January 1996 to December 2006. Patch tests with the Brazilian standard series and a complementary series were applied to all patients. RESULTS Diagnosis of ACD from nail varnish was made in 8% of cases (157 of 1,971). The most affected sites were the face and neck; however, involvement of some uncommon areas, such as periungual and perianal regions, was also observed. CONCLUSIONS ACD from nail polishes is a common event and recognition of the condition must be improved. Toluenesulfonamide formaldehyde resin (TSFR) was the most common allergen in the group studied.

FUNDAMENTOS: A dermatite alérgica de contato é freqüente, com variações de acordo com o grupo estudado. OBJETIVOS: Verificar a freqüência da dermatite alérgica de contato em idosos; demonstrar os principais sensibilizantes nesse grupo; comparar os resultados dos testes epicutâneos com um grupo de adultos atendidos no mesmo período. PACIENTES: Durante o período 1998-2003, entre os pacientes submetidos aos testes de contato na Clínica de Dermatologia da Santa Casa de São Paulo, selecionaram-se idosos (>65 anos) e adultos (20-65 anos). RESULTADOS: Foram avaliados 80 (9%) idosos e 581 (63%) adultos. Entre os idosos, 70 tiveram testes positivos, e 10, negativos. Nos adultos, 436 apresentaram testes positivos, e 145, negativos. A diferença entre os grupos em relação ao número de testes positivos e negativos foi estatisticamente significante (p= 0,02). Demonstrou-se maior freqüência de sensibilização nos idosos às seguintes substâncias - sulfato de níquel (p=0,001), perfume-mix (p=0,004), neomicina (p=0,0008), nitrofurazona (p=0,02), prometazina (p=0,03) e benzocaína (p=0,007). CONCLUSÕES: A dermatite alérgica de contato nos idosos é comum como em outras faixas etárias. As substâncias relacionadas aos medicamentos tópicos são importantes agentes etiológicos da dermatite alérgica de contato nesse grupo. BACKGROUND: Allergic contact dermatitis is a frequent condition and varies according to the population studied. OBJECTIVES: To verify the frequency of allergic contact dermatitis in elderly patients; to demonstrate the main sensitizers in this age group; to compare the results of the contact tests with those of a group of adults seen in the same period. Patients: From 1998 to 2003, elderly (over 65 years), and adults (aged 20-65 years) were selected among patients submitted to contact tests at the Dermatology Clinic of [Hospital] Santa Casa de Sao Paulo. RESULTS: Eighty (9%) elderly and 581(63%) adult patients were assessed; 70 elderly patients had positive tests and 10 had negative tests. In the adult group, 436 had positive tests and 145 negative tests. The difference between the groups was statistically significant (p=0.02). The most frequent sensitizers in the elderly group were nickel sulfate (p=0.001), fragrance-mix (p=0.004), neomycin (p=0.0008), nitrofurazone (p=0.02), promethazine (p=0.03) and benzocaine (p=0.007). CONCLUSIONS: Allergic contact dermatitis in the elderly is as frequent as in other age groups. The substances related to topical medicines are important etiologic agents of allergic contact dermatitis in elderly individuals.

The objectives of this study were (i) to determine the frequency of dermatoses caused by use of cosmetics in patients with specific complaints of reaction to cosmetic products, and (ii) to observe the main skin conditions frequently misunderstood by users as cosmetic reactions. 176 patients seen in a private office from 1999 to 2006, with complaint of dermatoses caused by cosmetics were examined. The clinical history, physical examination, relation between site of reaction and use of cosmetics were assessed. Of the patients examined, 154 (87.5%) were women and 22 (12.5%) men. About 90 (52%) patients had no skin condition related to cosmetics, 80 (45%) had dermatoses associated with cosmetics, and 6 patients (3%) had inconclusive results. Melasma, contact dermatitis to other products, and acne were the conditions that users associated more often to cosmetics. 14% of patients had skin lesions caused by inappropriate cosmetic use. To conclude, the true adverse reaction to cosmetics was not very common. In this study, dermatitis was associated with cosmetics in only 31% of patients with specific complaint of dermatitis caused by cosmetics. Therefore, 52% of patients misdiagnosed the condition and had other dermatoses, and 14% made inappropriate use of cosmetics.

Background: Hand eczema (HE) is a chronic multifactorial dermatosis with the presence of endogenous and exogenous factors in its pathogenesis. The etiologic diagnosis of hand eczema is often difficult. Objectives: The objectives of this study were (1) to detect clinical history and clinical examination data capable of differentiating HE types; (2) to determine the importance of patch tests for the etiologic diagnosis of HE; and (3) on the basis of the definitive diagnosis of HE type with the aid of patch tests, to obtain relevant data for appropriate patient guidance for the control of HE. Methods: A total of 250 patints with HE were studied over a period of 3 years (1993 to 1995). All patients were submitted to the battery of patch tests. Results and Conclusions: The results obtained led to the following conclusions: (1) Women are more predisposed to HE. (2) Work under moist conditions favors HE. (3) With respect to the regional location of HE, any region may be involved in any type of HE; however, involvement of the dorsal region is more common in allergic contact dermatitis (ACD), followed by contact dermatitis owing to primary irritation (ICD) and atopic dermatitis (AD). Location of HE on the dorsal surface of the fingers was mainly observed in ACD, followed by ICD and AD. (4) Patch tests should be part of the investigative routine of HE etiology. (5) The presence of allergy to metals in the clinical history of the patient in a relevant feature, because patch tests confirmed sensitization to nickel in 89% of cases. (6) Rubber components have high sensitization frequency in patients with HE. (7) When the patient reports worsening of HE after the use of rubber gloves, this indicates a probable sensitization to rubber components, mainly in patients with AD.

Background: Excited skin syndrome (ESS) occurs when, after a battery of patch tests is applied to patients with suspect allergic contact dermatitis, an excessive number of positive patch tests is obtained that are no longer reproduced when the patient is retested. Objective: This study was performed to verify the occurence of ESS when patch tests were applied to a population with a hypothetical diagnosis of allergic contact dermatitis, to determine the rate of positive test result loss among the tested patients who developed ESS, and to try to identify factors that might initiate the ESS. Methods: From January 1985 to May 1990, patch tests were performed on 1,500 patients referred to the Allergy Sector of the Dermatology Clinic of Santa Casa de Sao Paulo with a hypothetical diagnosis of contact dermatitis. Thirty-four of the 1,500 patients were considered because they showed three or more positive test results during the first phase of the patch tests. These patients were submitted to the retesting of substances with positive test results in the first phase. Results and Conclusions: Analysis of the results allowed us to conclude that the frequency of ESS in the 1,500 patients tested was 2.2% and that the number of lost test results between the first and the second phase was 175, showing a loss rate of positive test results of 63.5%. Regarding the facts that might interfere with the ESS, it was shown that (1) the loss rate of positive test results varied among patients, ie, polysensitized patients showed a lower rate of test result losses than monosensitized or bisensitized patients; (2) the longer the time of evolution of the chronic eczematous dermatitis, the higher the tendency to develop ESS; (3) ESS might be initiated by positive test results of weak, medium, or high intensity; (4) when the patch tests are applied close to one another, the positive test results may induce additional responses in the area; and (5) it was not possible to show statistically that the nature of certain substances interferes with the induction of ESS.

A retrospective study was carried out between 2006-2011. Six hundred and eighteen patients with suspected allergic contact dermatitis underwent the standard patch test series recommended by the Brazilian Contact Dermatitis Research Group. The aim of our study was to evaluate the variation of positive patch-test results from standard series year by year. The most frequently positive allergens were: nickel sulfate, thimerosal and potassium bichromate. Decrease of positive patch-test results over the years was statistically significant for: lanolin (p=0.01), neomycin (p=0.01) and anthraquinone (p=0.04). A follow-up study should be useful in determining which allergens could be excluded from standard series, as they may represent low sensitization risk. Estudo retrospectivo foi realizado entre 2006 e 2011 em 618 pacientes com hipótese diagnóstica de dermatite de contato submetidos à bateria padrão de testes de contato preconizada pelo Grupo Brasileiro de Estudos em Dermatite de Contato com o objetivo de avaliar a variação, a cada ano, da frequência de positividade para as substâncias da bateria. Os principais sensibilizantes foram sulfato de níquel, timerosal e bicromato de potássio. As substâncias com diminuição da frequência de sensibilização estatisticamente significante foram lanolina (p = 0,01), neomicina (p = 0,01) e antraquinona (p = 0,04). A continuação deste trabalho poderá contribuir para verificar aqueles componentes que poderão ser eliminados da bateria, por representarem pouco risco de sensibilização.

Whether parapsoriasis represents an early stage of T-cell cutaneous lymphoma is still the subject of controversy. We evaluated the efficacy of phototherapy in the treatment of parapsoriasis and its relation with TCCL. Patients diagnosed with parapsoriasis and treated with phototherapy PUVA or UVB-NB were selected. Between 1 to 8 years following treatment the evolution of their disease was evaluated. In 62 patients the cure rate was 79.3% and 17.2% showed improvement of the lesions. Only two patients developed full blown T-cell cutaneous lymphoma. Phototherapy is an excellent treatment for parapsoriasis, with high cure rates, regardless of the type of phototherapy employed. Of the 62 patients under study, parapsoriasis showed no general tendency to progress to T-cell cutaneous lymphoma. Há controvérsias se parapsoríase pode evoluir para linfoma Cutâneo de Células T. Neste trabalho avaliou-se eficácia da fototerapia no tratamento da parapsoríase e sua relação com linfoma Cutâneo de Células T. Selecionaram-se pacientes com parapsoríase tratados com PUVA ou UVB-NB. Após um-oito anos do tratamento, pacientes foram contatatos para avaliar a evolução da doença. Em 62 pacientes, a taxa de cura foi de 79,3%;17,2% apresentaram melhora de lesões. Apenas dois pacientes evoluíram para linfoma Cutâneo de Células T. A fototerapia mostrou-se eficaz no tratamento da parapsoríase, independente do tipo de fototerapia utilizada. Nos casos estudados, parapsóríase não mostrou tendência a se desenvolver em linfoma Cutâneo de Células T.

BACKGROUND: Background: Patch tests are an efficient method to confirm the etiological diagnosis of allergic contact dermatitis. OBJECTIVES: 1) To determine the permanence of results between two tests performed with an interval of at least one year, in patients with allergic contact dermatitis; 2) To compare the positive results according to rates of intensity; 3) To evaluate the permanence of sensitization according to each substance that was tested. METHODS: Patients with previous diagnosis of allergic contact dermatitis, confirmed by patch tests carried out between the years 2005 and 2008, underwent new testing, using the same methodology, and data was compared. RESULTS: A total of 1470 results of both tests on 49 patients were analyzed. The negative results remained in the second test in a rate of 96%, and 4% became positive (+) without relevance to the clinical history. Moreover, moderately (++) and strongly (+++) positive results were also maintained in, respectively, 86% and 100%. Nevertheless, weakly (+) positive results became negative in 65%. By ignoring all weakly (+) positive tests, the calculation of Kappa Index of Agreement Statistics between the two tests showed a value of 0.88. CONCLUSION: Patch tests showed to be reliable for negative, moderately (++) positive and strongly (+++) positive results, by reproducing the same standard of individual response to allergens. However, for weakly (+) positive results, tests were not reliable.

Publisher Summary This chapter presents an overview of some dermatological drugs, topical agents, and cosmetics. Artecoll® is a permanent synthetic cosmetic filler substance, composed of 80% bovine collagen and 20% polymethylacrylate. It is used for augmentation of deep wrinkles and is injected subdermally. The collagen is biodegradable with 2–4 months; however, the polymethylacrylate microspheres are nonbiodegradable and long-lasting cosmetic effects are achieved. There have been reports of granulomatous reactions at the sites of injection. These reactions develop within a few months to several years after the procedure. Ocular argyrosis has been reported after repeated exposure to silver-containing compounds, usually from topical medicinal solutions or occupational exposure. Hydroquinone has been used in skin-bleaching formulations for the treatment of hyperpigmentation and can cause short- and mid-term adverse effects such as exogenous ochronosis and leukoderma en confetti, irritant reactions, and allergic reactions. Long-term adverse effects such as nephrotoxicity and carcinogenicity have only been demonstrated in animals. It has also been found that application of talc to wounds (erosions, ulcers) or crusting and/or exudative dermatosis can give rise to scab formation, infection, and foreign body granulomas in the dermis

Publisher Summary This chapter discusses the adverse effects of dermatological drugs, topical agents, and cosmetics such as hair dyes, henna, pimecrolimus, and minoxidil. Previous studies have suggested an association between the use of hair dyes and some cancers. Several studies have found an association of nonHodgkin's lymphoma with the use of hair dyes. In recent years, contact dermatitis after henna tattoos has been attributed to the sensitizer paraphenylenediamine, which is used as an antioxidant and favours a long-lasting effect of the henna. Allergic contact dermatitis from pimecrolimus in a patient with tacrolimus allergy has been described, showing the possibility of cross-reactions among topical immunomodulators. There have been reports of hypotension and tachycardia after chronic scalp application of minoxidil, suggesting that topical minoxidil can be systemically absorbed. Phototherapy and photochemotherapy with aminolevulinic acid is also related to complications, pain is the main adverse effect of photodynamic therapy. Tretinoin application has led to sunburn, hypersensitivity reactions, contact dermatitis, and desquamation.

Apresenta-se o caso de uma profissional da área da saúde que desenvolveu reação de hipersensibilidade dos tipos I e IV à borracha. O quadro clínico mostrava dermatite eczematosa no dorso das mãos. O teste de contato foi positivo para o grupo tiuram, assim como o teste aberto com fragmento de luva após exposição de 20 minutos. A dosagem de IgE sérica (Rast) mostrou-se relevante. As reações aos alérgenos da borracha são frequentes entre os profissionais da saúde, devido ao contato constante com esse material. We present a case of a healthcare professional that developed type I and IV hypersensitivity reactions to rubber. During the clinical examination the patient showed eczematous dermatitis of the hands. The patch test was positive for thiuram group and an open test with a piece of glove was positive after 20 minutes of exposure. Allergen-specific IgE test (RAST) was relevant. Reactions to rubber allergens are frequent among healthcare professionals due to constant contact with this material.

FUNDAMENTOS: A dermatite de contato é uma dermatose comum e suas múltiplas causas dificultam seutratamento. OBJETIVO: O objetivo do estudo foi avaliar a frequência da sensibilização aos medicamentos de uso tópico, em serviço universitário; estudar as características da população afetada e identificar os principais sensibilizantes relacionados aos medicamentos tópicos. MÉTODOS: Realizou-se um estudo retrospectivo dos pacientes com hipótese diagnóstica de dermatite alérgica de contato e que foram submetidos a testes epicutâneos. Avaliaram-se os que tiveram diagnóstico final de dermatite alérgica de contato a medicamentos tópicos. RESULTADOS: Em um grupo de 329 pacientes submetidos a testes de contato, 42 (13%) tiveram testes de contato positivos e relevantes para medicamentos tópicos, pelo princípio ativo e/ou por outros componentes. Entre os testes positivos, 36 (85,7%) corresponderam aos princípios ativos e 28 (66,7%), a outros componentes das fórmulas, com alguns pacientes apresentando mais de um teste positivo. Entre os princípios ativos, a neomicina foi o mais frequente. CONCLUSÕES: Entre os pacientes estudados, a sensibilização aos medicamentos tópicos ocorreu em 13% dos casos, com discreta preferência pelo sexo feminino e maior número de casos entre pacientes brancos. Houve elevada frequência de dermatite alérgica de contato pela neomicina, agente de uso comum como automedicação e também como prescrição médica. BACKGROUND: Allergic Contact Dermatitis is a common type of dermatitis, but its multiple etiologies hinder its management. OBJECTIVE: the objective of this study was to evaluate the frequency of sensitization to topical drugs in a university center, to study the main characteristics of the affected population, and to identify the allergens related with the dermatitis. METHODS: a retrospective and descriptive study with patients submitted to patch tests. The study was conducted with subjects whose patch test to topical drugs was positive. RESULTS: 329 patients were submitted to patch tests and 42 (13%) had positive and relevant patch tests to topical drugs. Among these patients, 36 (85.7%) had positive patch tests to the principal component and 28 (66.7%) to the other components. Some patients had more than one sensitization. Neomycin was the most important allergen. CONCLUSIONS: Among the studied patients, sensitization to topical agents happened in 13% of the cases, with slight preference for females and Caucasians. There was elevated sensitization to neomycin, a popular agent among patients and medical doctors.

Background: Adolescents between the ages of 10 and 19 are exposed to a series of substances capable of causing contact dermatitis. Objectives: (1) To study the frequency and characteristics of allergic contact dermatitis in adolescents, (2) to characterize the group being studied, and (3) to verify the main sensitizing substances among this age group. Methods: From 1996 to 2001, 1,027 patients with a suspicion of contact dermatitis were analyzed, and patients between 10 and 19 years of age were selected. These patients were submitted to contact tests. Results: Among the 102 adolescents, 93 (91%) were female and 9 (9%) were male. The face was the area most affected by dermatosis. The contact tests were positive in 64 patients (56%), whereas in 45 (44%) they were negative. The main location of the contact dermatitis was the face (36%). The substances with higher frequencies of sensitization were nickel sulfate in 33 (31%) patients and tosylamide-formaldehyde resin in 13 (12%) patients. Conclusion: Contact dermatitis in adolescents was more frequent in white girls and on the face. The substances with greater frequency of sensitization were nickel sulfate and tosylamide-formaldehyde resin. These two substances are related to adolescent habits and behavior.

Background: Epicutaneous patch tests represent a practical and objective method that help in the etiologic diagnosis of allergic contact dermatitis. The technique of patch test application is an important factor in obtaining good results. Objectives: The aims of this study were (1) to determine whether the substances that form the test battery interfere with the patch test result and (2) to establish a rule for positioning the substances during patch test application. Methods: Two hundred patients were studied. The standard patch test battery was applied in 3 versions. The original, with the substances applied in alphabetical order was called version 1 (V1) and tested on the left back in all patients In 100 patients, on the right side, the same substances were tested but applied at different positions, avoiding the proximity of elements with a tendency to cross reaction and/or cosensitizing. This version of the battery was named version 2 (V2). Another 100 patients had V1 applied to the left back, and, on the right side, the version 3 of the battery (V3) was applied, consisting of the same allergens but placed close to those with a tendency for cross reaction and/or cosensitization. Results: In the group V1-V2, 163 results were positive in V1 and 124 in V2, with the difference being statistically significant ( P [lt ] .05). In the group V1-V3, 134 results were positive in V1 and 207 in V3, with the difference also being significant ( P [lt ] .005). The substances with the largest number of positive results, when tested close to other elements with a tendency for chemical affinity, were parabens, fragrance-mix, thimerosal, balsam of Peru, potassium dichromate, cobalt chloride, mercapto mix, and propylene glycol. Conclusions: (1) The substances of a patch test battery eliciting positive responses may interfere with test positivity to neighboring substances. (2) In addition to the already established techniques, the position of the substances forming the test battery needs to be determined; substances with a tendency to cross reaction or cosensitizing substances should be tested distant from one another, thus preventing the occurrence of false-positive results.