Diagnosis Of Allergic Contact Dermatitis Research Articles

Patch Test Results with the Latin American Baseline Series in a Colombian Population. 2016-2021.

Background: Contact dermatitis (CD) is one of the most prevalent skin diseases. It is commonly divided into irritant contact dermatitis (ICD) and allergic contact dermatitis (ACD). Patch testing is a procedure used to support the diagnosis of ACD. This test should be interpreted along with the clinical history and morphology of the skin lesions to determine clinical relevance. Objective: To describe the sensitization patterns of patients undergoing patch testing with the Latin American baseline series. Methods: A single-center retrospective study was performed. For the study, patients older than 18 years with a clinical diagnosis of contact dermatitis, who underwent patch testing using the Latin American baseline series were considered. These tests took place at the Alma Mater Hospital of Antioquia between January 1, 2016, and December 31, 2021. Results: A total of 648 patients were included. Patch tests were positive in 63% of cases, with a mean age of 51.5 years. Around 36.6% had atopy-related diseases. The main occupation was housework (30.7%). The hands were the most affected area in the body (31%). The main allergens were nickel sulfate (34%), sodium tetrachloropalladate (24.2%), and thimerosal (8.0%). Fifteen allergens had a percentage below 1%. Hydrocortisone and budesonide did not yield positive results. Conclusion: Nickel sulfate was the most frequent allergen, and women were the most affected. The information gathered could be useful for adjusting the allergens that should be included in the regional baseline series, taking into account the frequency found.

ALLERGIC CONTACT DERMATITIS AND ATOPIC DERMATITIS: HIGHLIGHTS OF THE OVERLAP SYNDROME

Introduction. The combination of atopic dermatitis (AD) with allergic contact dermatitis (ACD) or the occurrence of ACD on the background of atopic dermatitis is called the overlap syndrome. Studies have demonstrated several reasons why patients with AD have a similar or even increased risk of developing ACD compared to those without AD. Allergens and haptens are trigger factors in a group of patients with AD and ACD overlap syndrome. The aim of the study. To confirm the diagnosis of ACD in a group of patients with AD – diagnose the overlap syndrome and analyze which allergens and haptens were the trigger factors in this group. Materials and methods. To confirm IgE-dependent sensitization in atopic dermatitis, skin prick tests or determination of specific IgE in blood serum were performed. Skin patch tests (European series S-1000) were performed to determine the mechanisms of delayed-type hypersensitivity. Results. It was found that the highest specific weight of positive allergic reactions has been recorded in response to the following allergens: ticks, ticks/ambrosia, birch and mold. The absolute majority of patients demonstrated positive specific IgE-dependent sensitization to Dermatophagoides pteronyssinus and Dermatophagoides farinae – 24 (50%), in turn, on Ambrósia – 14 (29.2%), and on Alternaria alternata – 8 (16.7%). Also, the reaction was most often recorded to haptens: cobalt, nickel, formaldehyde, PPD, textile dyes. Deterioration of the clinical course and shortening of AD remission periods were observed due to the formation of ACD against the background of impaired skin barrier function and the presence of chronic immune inflammation. Conclusions. Patients with AD are more often diagnosed with ACD, which predictably worsens the course of AD. Patients with confirmed overlap syndrome "AD + ACD" most often show reactions to haptens: Cobalt, Nikel, Formaldehyde, PPD, Textile dye mix – and in the vast majority to 2 haptens or more in one patient.

Recognizing and Managing Allergic Contact Dermatitis: Focus on Major Allergens

Patch testing is the gold standard for the diagnosis of allergic contact dermatitis. The identification and avoidance of culprit allergen/s is essential in the treatment of this disease. Each year, new allergens are identified as emerging or important. The authors discuss allergens that are common, enduring, emergent, incompletely recognized and controversial for the practicing allergist and dermatologist. This Clinical Management Review will encompass a review of fragrances, preservatives, rubber, acrylates, metals, and medications, their common sources of exposure, controversies in diagnosis and patch testing, management and how to avoid those allergens. This review will also include practical aspects of diagnosis and management and will provide resources that can be used as guidance for physicians and patients on nickel, MCI/MI, fragrance, the most common allergens positive on patch testing.

[Translated article] Epidemiological, Clinical, and Allergic Profile of Psoriatic Patients. Evaluation of the Spanish Registry of Contact Dermatitis and Cutaneous Allergy (REIDAC)

BackgroundPsoriasis is a chronic inflammatory dermatosis whose clinical and topographic distribution requires differential diagnosis, or the possible association with allergic contact dermatitis (ACD), requiring patch testing (PT) as part of the diagnostic procedure. ObjectivesTo describe the epidemiological, clinical, and allergic profile of patients with a primary or secondary diagnosis of psoriasis undergoing PT and compare them with patients with a diagnosis of ACD at the end of the diagnostic process. MethodsCross-sectional study with data from REIDAC from 2018 through 2023 of selected patients with a diagnosis of psoriasis and/or ACD. ResultsA total of 11 502 patients were included, 513 of whom had been diagnosed with primary or secondary psoriasis, 3640 with ACD, and 108 with both diseases. Men were more predominant in the groups of patients with psoriasis, psoriasis+ACD, and lesions were more predominantly seen in the hands with little association with atopic factors vs the ACD group. The rate of positivity in PT to the 2022 Spanish battery of allergens was lower in the group with psoriasis only in 27% of the patients. The most common allergens found in the psoriasis group were also the most common ones found in the overall ACD population. ConclusionsOverall, 36.2% of psoriatic patients tested positive in PT to the 2022 Spanish battery of allergens, which proved that this association is not uncommon. Overall, psoriatic patients had a higher mean age, were more predominantly men, and showed more hand involvement.

The Contact Sensitivity of Turkish Children and Adolescents to European Baseline Series Allergens between 2013 and 2023.

Increasing the numbers of patch testing in suspected children increases the rate of diagnosis of allergic contact dermatitis and the identification of clinically relevant allergens. The aim of this study was to identify the most frequently observed allergens among Turkish children and adolescents patch-tested in 2013-2023. The patch test results of 160 patients (age ≤18) were analyzed retrospectively. The frequency of contact allergens and distribution of positive results in terms of sex, age group (children and adolescents), and the presence of atopic dermatitis (AD) were identified. Forty-nine patients (30.6%) (34 girls and 15 boys) exhibited positive patch test reactions to a minimum of one allergen, and contact sensitivity was statistically significantly higher in girls (P=0.034). The five most frequent allergens were nickel sulfate (10.6%), MCI/MI (8.1%), cobalt chloride (5.6%), p-phenylenediamine (PPD) (5%), and MI (3.5%). No significant association was observed between patch test positivity and age groups (P>.05). Nickel sulfate sensitivity was significantly higher in girls than in boys (P=.043). A positive reaction was detected in 31.3% of patients with AD and in 33.7% of those without (P>.05), and a statistically significant relationship was observed between contact sensitivity to fragrance allergens and AD (P=.046). Metals and preservatives represent the most frequent allergens in Turkish children and adolescents. Metal sensitivity is expected to decrease as legislation is enforced. Regulatory measures are now required to reduce MI and MCI/MI contact allergy in Turkey.

Allergic contact dermatitis caused by topical corticosteroids: A review for clinicoepidemiological presentation, evaluation, and management aspects

Dermatitis medicamentosa or contact dermatitis to topically applied medicaments, active ingredients or excipients, is encountered frequently in clinical practice and should be suspected in patients showing resistance to treatment despite adequate therapy and in patients, who complain of intolerance to a particular treatment. Topical corticosteroids are prescribed mostly in dermatology for their anti-inflammatory, antiproliferative, and immunosuppressive actions to treat various inflammatory dermatoses. These may act as allergens and produce immunoglobulin E-mediated immediate hypersensitivity (anaphylaxis, urticaria, angioedema, bronchospasm, vomiting, and cardiovascular collapse) or T-cell-mediated allergic contact dermatitis (ACD). Although it occurs less often and is not life threatening, ACD negatively impacts the quality of life by worsening preexisting dermatitis. The prevalence of hypersensitivity to these allergens varies across regions and periods of time depending on the clinical practice, prescribing habits, and types of cases studied. Over-the-counter availability of corticosteroids in multiple formulations in recent years may further compound the problem due to their indiscriminate and extensive use. Although about one-third of all cases of contact dermatitis are initiated or perpetuated by topical medicaments, the occurrence of contact dermatitis due to corticosteroids remains undersuspected. This is perhaps due to their anti-inflammatory and immunosuppressive properties that make it difficult to doubt and prove contact sensitivity that may be from a corticosteroid itself or to the additives and vehicles in the formulation. Patch testing can help identify the culprit agents in ACD but early diagnosis depends on clinical suspicion. Sensitization in contact dermatitis exhibits cross-reactivity patterns based on corticosteroid structure. Clinicoepidemiological presentation, evaluation, and management aspects of contact hypersensitivity reactions to corticosteroids are reviewed.

Perfil epidemiológico, clínico y alérgico en pacientes con psoriasis. Evaluación del Registro Español de Dermatitis de Contacto (REIDAC)

BackgroundPsoriasis is a chronic inflammatory dermatosis whose clinical and topographic distribution requires differential diagnosis, or the possible association with allergic contact dermatitis (ACD), requiring patch testing (PT) as part of the diagnostic procedure. ObjectivesTo describe the epidemiological, clinical, and allergic profile of patients with a primary or secondary diagnosis of psoriasis undergoing PT and compare them with patients with a diagnosis of ACD at the end of the diagnostic process. MethodsCross-sectional study with data from REIDAC from 2018 through 2023 of selected patients with a diagnosis of psoriasis and/or ACD. ResultsA total of 11 502 patients were included, 513 of whom had been diagnosed with primary or secondary psoriasis, 3640 with ACD, and 108 with both diseases. Men were more predominant in the groups of patients with psoriasis, psoriasis+ACD, and lesions were more predominantly seen in the hands with little association with atopic factors vs the ACD group. The rate of positivity in PT to the 2022 Spanish battery of allergens was lower in the group with psoriasis only in 27% of the patients. The most common allergens found in the psoriasis group were also the most common ones found in the overall ACD population. ConclusionsOverall, 36.2% of psoriatic patients tested positive in PT to the 2022 Spanish battery of allergens, which proved that this association is not uncommon. Overall, psoriatic patients had a higher mean age, were more predominantly men, and showed more hand involvement.

Diagnostic accuracy of patch testing based in clinical response to contact allergen restrictions in allergic contact dermatitis.

Background. Patch testing (PT) is used to identify substances that cause allergic contact dermatitis (ACD). However, the clinical effects of allergen restrictions following PT have not been thoroughly investigated. This study aims to assess the diagnostic accuracy of PT in patients suspected of having ACD. Methods. Prospective study. PT were performed in patients with clinical diagnosis of ACD. Patients with a positive PT (case group) had a strict restriction of the suspected substance for one month. In patients with negative patch testing (control group), allergen restriction was based in clinical history. Clinical reduction (CR) of at least 50% in disease activity (CR50%) after one month of allergen restriction was considered clinically relevant. Total control was defined as clinical reduction of at least 90% (CR90%). Results. From 400 patients, 66.2% had a positive PT. The sensitivity of PT to identify CR50% was 84%, specificity 47%, PPV 53%, and NPV 81%. Only 10.5% of patients achieved CR90%. Conclusions. The PT had moderate diagnostic accuracy. It could be useful as a screening, but a positive result should be confirmed with controlled allergen restriction. The low number of patients who achieved a 90% CR invites to reconsider the allergens included in PT and the mechanistic processes of the disease.

Gene profiling in active dermatitis lesions strengthens the diagnosis of allergic contact dermatitis

BackgroundDistinguishing between allergic and non-allergic forms of Contact Dermatitis (CD) is challenging and requires investigations based on patch-testing. Early detection of allergy biomarkers in active CD lesions could refine and simplify the management of CD patients. ObjectiveTo characterize the molecular signatures of active CD lesions. MethodsWe studied the expression of 12 allergy biomarkers by qRT-PCR in active lesions of 38 CD patients. Allergic CD (ACD) was diagnosed based on patch-test (PT) results and exposure assessment. Molecular signatures of active lesions, as well as positive PT reactions, were compared with those of reference chemical allergens and irritants. Results19 of the 38 CD patients reacted positively upon patch-testing and exposure assessment confirmed ACD diagnosis for 17 of them. Gene profiling of active CD lesions revealed two distinct molecular patterns: patients harboring signatures similar to reference allergens (n=23) or irritants (n=15). Among the 23 patients with an “allergy signature”, we found the 17 patients with confirmed ACD, while no culprit allergen was identified for the 6 other patients. Interestingly, the 15 patients without biomarker induction had negative PT, suggesting that they developed non-allergic CD reactions. ConclusionMolecular signatures from active skin lesions may help to stratify CD patients and predict those suffering from allergic contact dermatitis.

Issues of pathogenesis and treatment of contact dermatitis in children of the first year of life

The article presents the pathogenetic features of dermatitis in children of the first year of life, features of the clinical picture and approaches to therapy. Contact dermatitis is a fairly common pathology in young children. Previously, it was believed that the clinical manifestations in this group of children were mainly associated with simple contact dermatitis (SCD), but in recent years, studies have shown that contact sensibilization is quite common, and currently the diagnosis of allergic contact dermatitis (ACD) is not uncommon, but timely anti-inflammatory therapy prevents the formation of a focus of chronic inflammation. The prevalence of SCD and ACD in children of the first year of life, as well as the severity of skin inflammation, is associated with the existing structural features of the skin. Changes in the structures of the epidermis and dermis, characteristic of this age period, lead to easier skin damage when exposed to various irritants, both mechanical and chemical in nature, and the penetration of allergens into the skin. The peculiarity of the structure of blood vessels and increased vascular permeability is an important factor in the development and longer existence of local inflammation. The main condition for the effectiveness of treatment of dermatitis is the cessation of exposure to the substances that caused their development, and the main means of treating these conditions are topical glucocorticosteroids (TGCS). The article discusses cases of SCD and ACD in children of the first year of life, in which methylprednisolone aceponate in the form of 0.1% cream was used for external therapy. The choice in favor of this TGCS was made due to the absence of halogens in the methylprednisolone aceponate formula, the possibility of use from 4 months of age and in sensitive areas. During treatment, all patients had a good clinical effect and no side effects. The use of methylprednisolone aceponate in the form of 0.1% cream for SCD and ACD in children of the first year of life is a highly effective and safe remedy.

Patch Test Results Among Older Adults: A Retrospective Analysis of the North American Contact Dermatitis® Group Data (2009-2020).

Background: Allergic contact Dermatitis® (ACD) in older adults (OA) represents a significant health burden, but few studies examine the prevalence and characteristics of contact allergy and ACD in this population. Objective: To compare positive and clinically relevant patch test results in OA versus younger adults (YA) and children. Methods: Retrospective analysis of patch test results obtained in OA (≥65 years), YA (19-64 years), and children (≤18 years) by the North American Contact Dermatitis® Group, 2009 to 2020. Results: Of 28,177 patients patch tested, 5366 (19.0%) were OA. OA were more likely to have a final primary diagnosis of ACD as compared with YA (50.8% vs 49.2%, P = 0.035) and children (44.6%, P < 0.0001). The primary site of Dermatitis® also differed by age group, with OA having a higher proportion of Dermatitis® affecting the trunk, scalp, anogenital region, and "under clothing," and a lower proportion of Dermatitis® affecting the face, lips, and feet. Limitations: Retrospective design, lack of follow-up, and referral population. Conclusion: OA were as likely and were statistically even more likely to have a final primary diagnosis of ACD compared with YA and children. Anatomic site of Dermatitis® also differed by age group. This underscores the need for patch testing in OA when ACD is suspected.

What Is the Role of Allergic Contact Dermatitis in Patients with Lower Leg Ulcers?

To analyze the relationship between contact dermatitis and delayed wound healing, discuss the diagnosis and treatment of lower leg contact dermatitis, and provide an algorithm for the patient with a red leg and delayed wound healing. This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and nurses with an interest in skin and wound care. After participating in this educational activity, the participant will:1. Describe the nature of contact dermatitis.2. Distinguish between allergic and irritant contact dermatitis and the other major differential diagnoses of delayed wound healing in this clinical scenario.3. Outline the steps in the diagnosis of allergic contact dermatitis and irritant contact dermatitis and identify common haptens responsible for allergic contact dermatitis in patients with venous leg ulcers.4. Apply the algorithm for delayed wound healing on a background of lower leg dermatitis.

PD06 Efficacy of dupilumab in chronic actinic dermatitis

Abstract Chronic actinic dermatitis (CAD) is characterized by a photoexposed site dermatitis in association with objective evidence of photosensitivity, often arising on a background of atopic dermatitis (AD). Dupilumab is a monoclonal antibody that inhibits signalling of interleukin (IL)-4 and IL-13 and is licensed for the management of moderate-to-severe AD. To date, nine case reports have suggested that dupilumab can be clinically effective for CAD, yet only five cases had diagnostic baseline phototesting and only two cases could demonstrate objective improvement in photosensitivity on repeat testing. We report a retrospective case series from two UK photobiology units of 11 patients with concomitant AD and CAD treated with dupilumab. Inclusion criteria included baseline phototesting with an irradiation monochromator device confirming a diagnosis of CAD &amp;lt; 3 years prior to starting dupilumab, phototesting repeated after at least 16 weeks on dupilumab and all patients included were refractory or intolerant to at least one other systemic therapy prior to dupilumab. Eleven patients [82% male, median age 40 years (range 21–59) at diagnosis] of skin phototypes I–V were included. All patients had a pre-existing diagnosis of AD before the onset of CAD, and two patients also had a pre-existing diagnosis of allergic contact dermatitis. The average duration of dupilumab therapy prior to repeat phototesting was 15 months (range 4–44). Ten of 11 (91%) patients reported improvement in their AD in terms of both rash and pruritus. Five of 11 patients (45%) reported partial improvement in their subjective photosensitivity of whom two showed ultraviolet B monochromator improvement (3- to 6-fold). Six of 11 (55%) patients reported no clinical change in photosensitivity of whom two showed no improvement or worsening on phototesting; while four showed improvements, they remained in the severely photosensitive range on phototesting. While dupilumab is an effective therapy for moderate-to-severe AD, its potential benefit in managing CAD is more difficult to measure. In 91% of patients with CAD, dupilumab was associated with improvement in AD, while clinical or objective improvement in photosensitivity occurred in 82%, albeit sometimes only to a slight degree. However, these data suggest that, for patients with CAD and concomitant AD, reducing the eczematous response is beneficial and that dupilumab is a treatment worth exploring for this patient cohort for whom other treatment options are limited. Prospective studies of dupilumab in CAD are required to further evaluate its utility in this therapeutically challenging condition.

Analysis of patch testing results in patients with contact dermatitis in Istanbul, Turkey, from 2012 to 2022.

Allergens responsible for allergic contact dermatitis (ACD) differ between populations. They can even change over the years with the effect of environmental factors. To evaluate the results of patch testing performed in our center. In this study, the thin-layer rapid-use epicutaneous (T.R.U.E.) test results of patients with a diagnosis of ACD between 2012 and 2022 were retrospectively evaluated. In 431 (42.5%) of the total 1012 patients, a positive reaction to at least one allergen was detected in the patch test. Allergen positivity was most detected for nickel sulphate (16.8%), gold sodium thiosulfate (GST) (6.9%), thimerosal (4.2%), fragrance mix (3.4%), carba mix (3.2%), and cobalt dichloride (2.9%). Nickel sulfate and GST sensitivity was found to be significantly higher in women, fragrance mix sensitivity in men, thimerosal sensitivity in individuals aged under 40 years, colophony and balsam of Peru sensitivity in head and neck dermatitis, and carba mix and thiuram mix sensitivity in atopic individuals. This study presents comprehensive data from Turkey concerning the sensitivity frequencies for allergens included in the T.R.U.E. test.

North American Contact Dermatitis Group Patch Test Results: 2019-2020.

Background: Patch testing is an important diagnostic tool for assessment of allergic contact dermatitis (ACD). Objective: This study documents the North American Contact Dermatitis Group (NACDG) patch testing results from January 1, 2019, to December 31, 2020. Methods: At 13 centers in North America, patients were tested in a standardized manner with a screening series of 80 allergens, and, as indicated, supplemental allergens. Results: Overall, 4121 patients were tested; 2871 (69.7%) had at least 1 positive/allergic patch test reaction and 2095 patients (51.2%) had a primary diagnosis of ACD. The most commonly positive allergens were nickel (18.2%), methylisothiazolinone (MI) (13.8%), fragrance mix (FM) I (12.8%), hydroperoxides of linalool (HPL) (11.1%), and benzisothiazolinone (BIT) (10.4%). Compared with that of 2017-2018, prevalence of top 20 allergens statistically increased for FM I, HPL, BIT, propolis, and hydroperoxides of limonene (3.5%). For the first time, MI positivity did not increase between reporting periods. Approximately one-fifth of patients (20.3%) had ≥1 clinically relevant reaction(s) to allergens/substances not on the NACDG series. Conclusions: The epidemic of MI contact allergy in North America may have reached a plateau. Patch testing using a robust screening series, and supplemental allergens as indicated, is necessary for comprehensive evaluation of ACD.

Allergic Contact Dermatitis in the Older Adults: A Comparative Cross-Sectional Study.

Background: Allergic contact dermatitis (ACD) is a significant health problem in older adults. Reports in the literature regarding the prevalence of ACD in older adults are various and inconsistent. In contrast, the data regarding contact irritant dermatitis are more consistent. Objective: To compare ACD characteristics in older adults versus the adult population aged 18-45 years. Methods: We conducted a retrospective controlled study. Data were obtained from the medical records of 4199 patients. We collected information regarding age, gender, atopic diathesis, anatomical distribution of the rash, reactions to patch tests, and final diagnosis. Results: The frequency of positive reactions in patch testing was lower in the older adult group than in the younger population, but the frequency of clinically relevant positive reactions was higher in the older adults. There was no statistically significant difference in the final diagnosis of ACD between the groups. The most common allergens among the older adult population were fragrance mix, preservatives (Methylchloroisothiazolinone/methylisothiazolinone [MCI/MI]), and nickel sulfate. Conclusion: This study, the first of its kind in Israel to include a large group of older adult patients, contributes to a better understanding of clinical parameters related to ACD among older adults. Consequently, it will hopefully contribute to lowering the disease burden.

The novel questionnaire assessing occupational exposure to the risk factors of contact allergy among health professionals.

Skin diseases account for about 7% of all occupational diseases in Europe. Allergic contact dermatitis (ACD) is one of the most common occupational skin diseases. Therefore, it constitutes the major health and economic problem. Increasing the detectability of ACD would significantly improve the quality of life of patients and their work efficiency. To design a questionnaire facilitating the diagnosis of ACD in work environment of healthcare providers. The initial questionnaire consisted of 53 questions related to ACD and exposure to various occupational hazards. On its basis, a scale of exposure to occupational skin diseases (OSDES-49) was created. The reliability of the scale was measured using the internal consistency test of the scale. It was assumed that individual items of the scale would be correlated with the total score if the Kleine and Nunnally criteria were met. The Kleine and Nunnally criteria were met by 16 out of 49 items on the scale. OSDES-49 results were strongly correlated with the assessment using a questionnaire consisting of only 16 items (OSDES-16). Spearman's rank correlation coefficient was rho = 0.850 and p < 0.001. Results of the study showed that in any further screening tests, the OSDES-16 scale is reliable. The use of OSDES-16 reduces the time of initial diagnostics and simplifies it.

Results of the patch tests with European baseline series in children: Five years of experience from a single center in Turkey and a review of the literature.

Pediatric allergic contact dermatitis (ACD) is increasingly prevalent. Patch testing is the gold-standard diagnostic method. Our study aimed to identify common contact-sensitizing allergens in Turkish children. We retrospectively analyzed the patch test results and characteristics of 191 pediatric patients [114 (59.7%) females, 77 (40.3%) males], who received the diagnosis of allergic contact dermatitis between 2015 and 2019. The mean age of the patients was 12.2 years (range 4-18 years). Thirty-six (18.8%) of the patients in the study group had positive patch test outcomes with 56 positive allergens. Girls had a significantly higher rate of total positive patch test results than boys (75%/25%; p=0.003, p < 0.05). The most frequent four allergens were nickel sulfate (n=20, 10.4%), cobalt chloride (n=6, 3.14%), p-phenylenediamine (n=5, 2.61%), Methylchloroisothiazolinone/methylisothiazolinone (n=5, 2.61%), respectively. In our study, we discovered that in addition to the frequently encountered metal allergens such as nickel and cobalt, p-phenylenediamine and Methylchloroisothiazolinone/methylisothiazolinone sensitivities were frequent in the Turkish population. p-phenylenediamine sensitization can cause serious systemic dermatitis during the lifetime of children. We suggest that in Turkey personal care and hygiene products containing Methylchloroisothiazolinone/methylisothiazolinone should be legally regulated. Since childhood contact dermatitis may have an impact on the quality of life by influencing family and social life, suspected allergens should be detected as early as possible.

Abstract 13109: Pacemaker Mediated Contact Allergy to Thiuram and Paraphenylenediamine

Introduction: Allergic contact dermatitis to cardiac rhythm devices (CRD) has been reported sporadically from the early 1980s to present. Most of these cases involve allergic reactions to direct contact agents such as nickel, silicone, titanium, cobalt, epoxy resin, mercury, polysulfone, polyurethane and polychloroparaxylene. Our case is unique in that the strongest allergic reaction was with thiuram and P-phenylenediamine (PPD), which has only been documented once since the advent of permanent pacemakers (PPM) Case: 58-year old male with history of hypertension and coronary artery disease presented with palpitations and fatigue. Holter monitoring demonstrated tachybrady syndrome and he underwent dual chamber PPM implantation (L331 Accolade TM MRI - Boston Scientific Inc). Eight weeks later he presented with new onset rash around his neck and the surgical site. PPM allergy was suspected, as patient did not respond to empiric antibiotics. He underwent PPM and lead extraction. Decision was made to observe patient without immediate re-implantation of PPM. Skin patch testing was strongly positive to thiuram and PPD. Final diagnosis of allergic contact dermatitis was made and patient’s condition improved. Discussion: Thiuram and PPD, the raw materials used in the production of silicone rubber, encase pacemaker headers and leads. Individuals typically get sensitized to PPD by using hair dyes or temporary henna tattooing. The device used in our patient contained the same compounds. No studies to date document the true incidence and/or prevalence of allergic reactions to pacemaker components. One non-randomized retrospective trial reported benefits of skin patch testing before CRD implantation in patients who had a history of allergy to metals. Future trials are warranted to further evaluate the efficacy and benefits of pre-implantation skin testing and if it would benefit the population as a whole.

Functional Roles of Exosomes in Allergic Contact Dermatitis.

Allergic contact dermatitis (ACD) is an allergen-specific T-cell-mediated inflammatory response, albeit with unclear pathogenesis. Exosomes are nanoscale extracellular vesicles secreted by several cell types and widely distributed in various biological fluids. Exosomes affect the occurrence and development of ACD through immunoregulation among other ways. Nevertheless, the role of exosomes in ACD warrants further clarification. This review examines the progress of research into exosomes and their involvement in the pathogenesis, diagnosis, and treatment of ACD and provides ideas for exploring new diagnostic and treatment methods for this disease.