Dermatitis®

Patch testing is the most important diagnostic tool for the assessment of allergic contact dermatitis.

This study documents the North American Contact Dermatitis Group (NACDG) patch testing results from January 1, 2013, to December 31, 2014.

At 13 centers in North America, patients were tested in a standardized manner with a screening series of 70 allergens. Data were manually verified and entered into a central database. Descriptive frequencies were calculated, and trends were analyzed using χ² test.

A total of 4871 patients were tested. There were 3255 patients (66.8%) who had at least 1 positive reaction and 2412 patients (49.5%) who were ultimately determined to have a primary diagnosis of allergic contact dermatitis. A total of 434 patients (8.9%) had occupationally related skin disease. There were 9726 positive allergic reactions. Compared with the previous reporting periods (2011–2012 and 2001–2012, including at least three 2-year cycles), positive reaction rates for the top 25 screening allergens statistically increased for 2 allergens: methylchloroisothiazolinone/methylisothiazolinone (6.4%; risk ratios, 1.26 [1.07–1.50] and 2.08 [1.84–2.37]) and hydroxyethyl methacrylate (2.6%; risk ratios, 1.34 [1.02–1.76] and 1.23 [1.00–1.51]). Methylisothiazolinone, which was added to the screening series for this 2013–2014 cycle, had the third highest positive reaction rate of allergens tested (10.9%). Four other newly added allergen preparations—formaldehyde 2% (7%), diphenylguanidine (3.8%), propylene glycol 100% (2.8%), and benzophenone-4 (2.1%)—all had reaction rates greater than 2%. Twenty-one percent of tested patients had at least 1 relevant allergic reaction to an allergen not on the NACDG series; 14.6% of these were occupationally related. The T.R.U.E. TEST (SmartPractice Denmark, Hillerød, Denmark) would have hypothetically missed one quarter to one third of reactions detected by the NACDG screening series.

These results confirm that the epidemic of sensitivity to methylisothiazolinone previously documented in Europe is also occurring in North America. Patch testing with allergens beyond a standard screening tray is necessary for the complete evaluation of occupational and nonoccupational allergic contact dermatitis.

Contact dermatoses are common in mechanic and repair occupations.

This study aimed to (1) estimate the prevalence of occupationally related contact dermatitis among mechanics/repairers patch tested from 1998 to 2014 by the North American Contact Dermatitis Group, (2) characterize responsible allergens and irritants, and their sources, and (3) compare results among 3 occupational subgroups (mechanics, electrical/electronic, and other).

A cross-sectional analysis of patients patch tested by the North American Contact Dermatitis Group between 1998 and 2014.

Of 38,784 patients patch tested, 691 (1.8%) were mechanics/repairers. Male sex (93.5%) and hand involvement (59.5%) were common overall. Occupationally related skin disease was more prevalent among vehicle and mobile equipment mechanics/repairers (52.7%) and other mechanics/repairers (41.4%) than electrical/electronic equipment mechanics/repairers (21.3%). Overall, carba mix, thiuram mix, and methylchloroisothiazolone/methylisothiazolone were the most common occupation-related clinically relevant allergens. Gloves, automotive vehicles, solvents, oils, lubricants, and fuels were the most common sources of responsible allergens.

Common occupationally related allergens included rubber accelerators and the preservative methylchloroisothiazolone/methylisothiazolone.

Corticosteroids may cause delayed hypersensitivity. On the basis of structure, the following 4 groups of corticosteroids are recognized: A, B, C, and D (subdivided into D1 and D2). More recently, a newer classification system subdivides corticosteroids into groups 1, 2, and 3. Cross-reactions are unpredictable. The objective of this study was to describe positive patch test and co-reaction patterns to corticosteroids.

A retrospective analysis of 17,978 patients patch tested by the North American Contact Dermatitis Group between 2007 and 2014 was performed. Corticosteroids tested during this period included the following: tixocortol-21-pivalate 1.0% petroleum (pet), budesonide 0.1% pet, triamcinolone acetonide 1.0% pet, desoximetasone 1.0% pet, clobetasol-17-propionate 1.0% pet, and hydrocortisone-17-butyrate (HC-17-B) 1.0% (pet and alcohol). Overall, 4.12% (n = 741) of patients had 1 or more positive reactions to corticosteroids. Tixocortol-21-pivalate positivity was the most common (2.26%), followed by budesonide (0.87%), HC-17-B (0.43%), clobetasol-17-proprionate (0.32%), and desoximetasone (0.16%). Reaction strength was strong (++ or +++) in almost twice as many tixocortol and budesonide reactions (>64%) as compared with the other 3 corticosteroids (<34.5%). Of the patients with positive corticosteroid reactions (n = 741), most (70.7%) had sensitivity to only 1 corticosteroid. Co-reactivity was highest between desoximetasone and budesonide.

Sensitivity to corticosteroids is important. Consistent with other studies, the highest frequency of corticosteroid positivity was seen in group A (tixocortol-21-pivalate), followed by group B (budesonide) and D2 (HC-17-B). Co-reactivity varied; more studies are needed to fully understand structural cross-reactivity.

Although there are several case reports of wet wipe–associated contact dermatitis, the prevalence of wipes as a source of allergic contact dermatitis in larger populations and the responsible allergens are largely unknown.

The aim of the study was to determine the prevalence of wet wipes as a source of contact allergy and the most commonly associated allergens in a North American tertiary referral patch test population.

Data collected from 2011 to 2014 by the North American Contact Dermatitis Group was used to conduct a retrospective cross-sectional analysis of patient demographics and patch test results associated with the triple-digit source code for “wet wipe.”

Of the 9037 patients patch tested during the study period, 79 (0.9%) had a positive patch test reaction to an allergen identified with a wet wipe source. The most commonly associated allergens were preservatives, including the following: methylisothiazolinone (MI) (59.0%), methylchloroisothiazolinone (MCI)/MI (35.6%), bronopol (2-bromo-2-nitropropane-1,3-diol) (27.4%), and iodopropynyl butylcarbamate (12.3%). Fragrance (combined) represented 12.3%. Anal/genital dermatitis was 15 times more likely (P < 0.0001) in those with wet wipe allergy. More than 92% of patients with wipe–associated contact allergy had their contact allergens detected by the North American Contact Dermatitis Group screening series.

Wet wipes are an important source of contact allergy. Preservatives are the main allergens, especially isothiazolinones.

Allergic perineal dermatitis (PD) due to diaper wipes, topical medicaments, or diapers has been reported. Although patch testing is the criterion standard for detection of allergic contact dermatitis in children, this is limited by body surface area, decreased tolerance of the patch testing procedure, and increased false-positive rates due to irritant reactions. Therefore, a targeted patch testing series is necessary to better screen diapered infants for possible allergic PD.

We propose 2 patch test series (PD series 1 and 2) to screen infants with possible allergic PD.

Allergens are chosen using existing sensitization data of common allergens in children, published case reports, and the collective experience of American Contact Dermatitis Society members through an electronic survey.

PD series 1 includes 23 potential allergens found in wet wipes and topical diaper preparations. PD series 2 contains 10 potential allergens most commonly found in diapers.

We believe that these judiciously chosen patch test series will increase the yield of detecting the causes of allergic PD while not exposing children to an unnecessarily large screening patch test panel.

There is no clear consensus among orthopedic surgeons concerning metal hypersensitivity screening and orthopedic implants.

This study investigated practices and opinions about metal hypersensitivity and orthopedic implants via a survey administered to practicing orthopedists.

A questionnaire was sent to members of the Pennsylvania Orthopaedic Society electronically. Respondents were asked about preoperative and postoperative screening habits concerning metal hypersensitivity and implants.

Forty-four physicians completed the survey. Only 11% of respondents reported that they always or often screen patients for metal hypersensitivity. Fifty percent of respondents stated that they only rarely refer patients for patch testing (and the remainder never do). If, however, patients were found to have a positive patch test, most providers were very likely to use a different implant. Other respondents were skeptical of the relationship between metal hypersensitivity and implant failure. Dermatitis, pain, and loosening were common reasons for postoperative testing. Seventy percent of respondents said that patch testing rarely or never changed their decision making.

This study is reflective of the lack of consensus between orthopedists regarding patch testing. It demonstrates the diversity of opinions among orthopedists, the need for additional dialogue between orthopedic and dermatology specialties, and the need for larger studies investigating outcomes and metal hypersensitivity.

Preservatives are known causes of allergic contact dermatitis.

The aim of this study was to determine the prevalence of preservatives in each product category in the Contact Allergen Management Program and compare prevalence with reported rates of allergic contact dermatitis.

Contact Allergen Management Program product information was queried based on the 53 approved preservatives for cosmetic products by the European Union and Association of Southeast Asian Nations plus 5 additional preservatives used in US products.

Phenoxyethanol and parabens were the most common preservatives with 23.9% of products containing phenoxyethanol and 20.75% of products containing parabens. Methylisothiazolinone (MI) was found in 12.9% of products, most commonly in hair care and household products. Preservatives like MI and methylchloroisothiazolinone (MCI) that are both common in products and have a high incidence of allergic contact dermatitis are of greatest concern as contact allergy hazards. Phenoxyethanol and parabens are common and have weak sensitizing power, making them preferred preservatives.

Evaluating the prevalence of preservatives provides important information on allergen exposures. Using current positive reaction rates, the risk of sensitization to a given preservative can be more accurately estimated and may affect the use of certain preservatives by industry in the future.