Patch Testing With Nickel, Cobalt, and Chromium in Patients With Suspected Allergic Contact Dermatitis.

Background: Allergic contact dermatitis is frequently caused by metals, including multiple metals simultaneously. Objectives: To assess characteristics and associations of positive and clinically relevant patch test (PT) reactions with solitary and concurrent metal sensitization. Methods: A retrospective analysis of PT results for nickel, cobalt, and/or chromium from the North American Contact Dermatitis Group between 2001 and 2018 (n = 43,522). Results: 18.0% had a positive/allergic reaction to nickel sulfate hexahydrate, 7.3% to cobalt chloride hexahydrate, and 3.0% to potassium dichromate. 87.9% patients had a currently relevant reaction to 0, 9.4% to 1, and 2.7% to multiple metals tested. Patients with 1 versus no currently relevant reactions to metal were more likely to have a primary dermatitis site of trunk, feet, and ears; patients with currently relevant reactions to multiple metals had more dermatitis affecting the trunk and ears. Metal sources varied by co-reacting metal, especially for patients with cobalt and chromium allergy. Jewelry was the most commonly identified source of nickel and cobalt for both solitary and concurrent metal allergy. Conclusions: Sensitization to multiple metals occurred in 6% of patients. Allergen sources varied between patients with sensitivity to 1 metal versus those who had concurrent sensitivity to cobalt and/or chromium.

Patch Testing to Paraphenylenediamine: The North American Contact Dermatitis Group Experience (1994-2018).

Background/Objectives: Paraphenylenediamine (PPD) is an aromatic amine dye that may cause allergic contact dermatitis. This study examines the epidemiology of allergic patch test reactions to PPD. Methods: This retrospective analysis characterizes individuals tested to PPD (1% petrolatum) by the North American Contact Dermatitis Group (1994-2018). Demographics and dermatitis site(s) were compared between PPD-allergic and PPD-negative patients. PPD reactions were analyzed by reaction strength, clinical relevance, occupational relatedness, and source as well as coreactivity with structurally related compounds. Results: Of 54,917 patients tested to PPD, 3095 (5.6%) had an allergic patch test reaction. Compared with PPD-negative patients, PPD-allergic patients had significantly greater odds of age >40 years (odds ratio [OR] 1.55 [95% confidence interval; CI 1.43-1.69]) and female gender (OR 1.52 [95% CI 1.41-1.66]), but lower odds of being White (OR 0.66 [95% CI 0.60-0.71]). The most common primary anatomic sites of dermatitis were face (25.5%), hands (21.9%), and scattered/generalized pattern (15.5%). Over half (55.3%) of PPD reactions were ++ or +++ at the final reading and 60.9% were currently relevant. Common exposure sources included hair dye (73.5%) and clothing/shoes/apparel (3.9%). Occupationally related reactions occurred in 8.3%, most commonly in hairdressers/cosmetologists (72.8%). The most common coreactions were benzocaine (11.3%), N-isopropyl-N'-phenyl-p-phenylenediamine (6.7%), disperse dye mix (6.5%), and black rubber mix (5.1%). Conclusions: The 24-year percentage of allergic reactions to PPD was 5.6%. PPD allergy was associated with female gender and age >40 years. PPD allergic patients were less likely to be White. Allergic reactions were usually clinically relevant and hair dye was the most frequently identified source.

Patch Testing to Chlorhexidine Digluconate, 1% Aqueous: North American Contact Dermatitis Group Experience, 2015-2020.

Background: Chlorhexidine is an antiseptic that may cause allergic contact dermatitis. Objectives: To describe the epidemiology of chlorhexidine allergy and characterize positive patch test reactions. Methods: This retrospective study analyzed patients patch tested to chlorhexidine digluconate 1% aqueous by the North American Contact Dermatitis Group, 2015-2020. Results: Of 14,731 patients tested to chlorhexidine digluconate, 107 (0.7%) had an allergic reaction; of these, 56 (52.3%) reactions were currently clinically relevant. Most (59%) reactions were mild (+), followed by strong (++, 18.7%) and very strong (+++, 6.5%). Common primary dermatitis anatomic sites in chlorhexidine-positive patients were hands (26.4%), face (24.5%), and scattered/generalized distribution (17.9%). Compared with negative patients, chlorhexidine-positive patients were significantly more likely to have dermatitis involving the trunk (11.3% vs 5.1%; P = 0.0036). The most commonly identified source category was skin/health care products (n = 41, 38.3%). Only 11 (10.3%) chlorhexidine reactions were occupationally related; of these, 81.8% were in health care workers. Conclusions: Chlorhexidine digluconate allergy is uncommon, but often clinically relevant. Involvement of the hands, face, and scattered generalized patterns was frequent. Occupationally related reactions were found predominantly in health care workers.

Contact dermatitis.

Contact dermatitis (CD) is among the most common inflammatory dermatological conditions and includes allergic CD, photoallergic CD, irritant CD, photoirritant CD (also called phototoxic CD) and protein CD. Occupational CD can be of any type and is the most prevalent occupational skin disease. Each CD type is characterized by different immunological mechanisms and/or requisite exposures. Clinical manifestations of CD vary widely and multiple subtypes may occur simultaneously. The diagnosis relies on clinical presentation, thorough exposure assessment and evaluation with techniques such as patch testing and skin-prick testing. Management is based on patient education, avoidance strategies of specific substances, and topical treatments; in severe or recalcitrant cases, which can negatively affect the quality of life of patients, systemic medications may be needed.

A Simulation-Based Workshop to Improve Dermatologists' Communication Skills: A Pilot for Continuing Medical Education.

INTRODUCTION: Communication skills influence the quality of health care and patient experience; both may affect provider reimbursement. There are few opportunities available for practicing physicians to receive direct feedback on communication in patient encounters. The purpose of this simulation-based patient encounter workshop was for dermatologists to practice and obtain feedback on their communication skills. METHODS: In March 2016, dermatologists participated in a workshop with four simulated patient encounters. Cases were developed based on a prior needs assessment. Standardized patient educators evaluated participants' communication using the Master Interview Rating Scale and provided verbal feedback. Physicians rated the usefulness of the simulation and the feedback received through a survey upon workshop completion. RESULTS: Of the 170 physicians who registered, 103 participated in the simulation. The workshop was highly rated in meeting its three learning objectives (score of 4.5-4.6 out of a maximum score of 5). The lowest-rated communication skills were as follows: allowing the patient to share their narrative thread (3.1), summarizing the patient's history from the provider (3.8), and assessing patient understanding (3.8). CONCLUSIONS: Participants reported that this communication workshop effectively satisfied its learning objectives. Opportunities to practice and improve communication skills as part of continuing medical education will benefit the clinical experience of patients and physicians alike, and the workshop may be formatted to serve physicians of other specialties. The lowest-scoring communication areas identified in this study present an opportunity to develop a tailored curriculum for physician-patient communication in the future.

Patient Reported Improvement After Patch Testing and Allergen Avoidance Counseling: A Retrospective Analysis.

INTRODUCTION: Our objectives were to assess patient-reported improvement after patch testing at the 2-3-month follow-up visit in patients referred for patch testing with relevant positive patch test reactions at the University of California, San Francisco. METHODS: Cross-sectional analyses of patients patch tested between 2013 and 2016 who returned for a follow-up visit approximately 2-3 months after patch testing. We examined positive patch test results considered of definite, probable or possible relevance to the patient's eczematous eruptions. Patients reported improvement after patch testing as a percentage: 0-100%. Patients were categorized into four groups: (1) those that reported no improvement or worsened, (2) those that reported > 0% and ≤ 60% improvement, (3) those that reported > 60% but < 100% improvement and (4) those that reported 100% improvement. Secondary measures included the association of allergens, gender, age and location of the rash. RESULTS: The majority (81%) of patients seen at follow-up reported improvement after patch testing. Women reported more improvement than men with statistical significance. Notably, there does not appear to be a statistically significant relationship in patient-reported improvement and age, atopy, strength of a the patient's positive reactions, number of positive reactions and follow-up time or with potential systemic contact allergens (i.e., balsam of Peru, nickel, chrome and cobalt). CONCLUSION: We find the large percentage of patients that self-report global benefit from patch testing encouraging, as we believe this to be a powerful measure of disease and symptom activity, as well as quality of life. The gender differences we found contradict the previous literature.

Positive patch-test reactions to propylene glycol: a retrospective cross-sectional analysis from the North American Contact Dermatitis Group, 1996 to 2006.

BACKGROUND: Propylene glycol (PG) may cause allergic or irritant contact dermatitis. It primarily functions as a vehicle, solvent, or emulsifier in cosmetics and topical medications. OBJECTIVES: To characterize the prevalence of positive patch-test reactions to PG and the epidemiology of affected patients. METHODS: Retrospective analysis of cross-sectional data compiled by the North American Contact Dermatitis Group (NACDG) from 1996 to 2006. RESULTS: Of 23,359 patients, 810 (3.5%) had allergic patch-test reactions to 30% PG; 12.8% of the reactions were of definite clinical relevance (positive reaction to a personal product containing PG), 88.3% were considered to be currently relevant (definite, probable, or possible relevance), and 4.2% of reactions were occupation related, most commonly to mechanical and motor vehicle occupations. Common sources of PG were personal care products (creams, lotions, and cosmetics, 53.8%), topical corticosteroids (18.3%), and other topical medicaments (10.1%). In patients positive only to PG (n = 135), the face was most commonly affected (25.9%), followed by a scattered or generalized pattern (23.7%). The most common concomitant reactions included reactions to Myroxilon pereirae, fragrance mix, formaldehyde, bacitracin, methyldibromoglutaronitrile/phenoxyethanol, carba mix, and tixocortol pivalate. CONCLUSIONS: In this select population of patients referred for patch testing, allergic reactions to PG were often currently clinically relevant but were rarely related to occupation. The most common sources were personal care products and topical corticosteroids.

Solar urticaria.

Solar urticaria is a relatively rare immunoglobulin E-mediated photodermatosis that is caused by specific, yet diverse wavelengths of light. The history, epidemiology, clinical manifestations, histology, etiology/pathogenesis, differential diagnosis, treatment, course, and prognosis of solar urticaria are reviewed herein.

Contact dermatitis associated with food: retrospective cross-sectional analysis of North American Contact Dermatitis Group data, 2001-2004.

BACKGROUND: Allergic and irritant contact dermatitis to food is likely underreported. OBJECTIVES: To characterize relevant allergens and irritants associated with food in patients referred to the North American Contact Dermatitis Group (NACDG) for patch testing. METHODS: Retrospective analysis of cross-sectional data from the NACDG from 2001 to 2004. RESULTS: Of 10,061 patch-tested patients, 109 (1.1%) had a total of 122 reactions associated with food. Approximately two-thirds of patients (66%) were female, and one-third (36%) were atopic. The hands were the most common sites of dermatitis (36.7%). There were 78 currently relevant (definite, probable, or possible) allergic reactions to NACDG standard series allergens with a food source; the most common allergen was nickel (48.7%), followed by Myroxilon pereirae (balsam of Peru) (20.6%) and propylene glycol (6.4%). Twenty allergic reactions to non-NACDG standard allergens and 24 relevant food irritants were also identified. Overall, 21% (25 of 122) of all reactions (irritant and allergic) were occupation related; the majority of these (17 of 25) were relevant irritant reactions. Cooks were the most commonly affected occupational group (40%). CONCLUSIONS: In this limited data set, nickel, Myroxilon pereirae, and propylene glycol were the most common allergens identified with a food source. Of food-related occupational disease, irritation was more common than allergy.