Concentrations and stability of methyl methacrylate, glutaraldehyde, formaldehyde and nickel sulfate in commercial patch test allergen preparations.

BACKGROUND: Epicutaneous patch tests are used to reproduce allergy and diagnose allergic contact dermatitis. Reliable allergen test preparations are required. OBJECTIVES: The purpose of the present study was to measure the actual concentrations of nickel(II) sulfate hexahydrate (NiSO4 ), methyl methacrylate, formaldehyde, and glutaraldehyde, and to compare them with the labelled concentrations, in commercial patch test allergen preparations found in dermatology clinics where patch testing is routinely performed. MATERIALS AND METHODS: The commercial in-date and out-of-date patch test allergen preparations concentrations of NiSO4 , methyl methacrylate, formaldehyde and glutaraldehyde from one to three participating clinics were analysed with chromatographic or wet chemical techniques. RESULTS: NiSO4 and formaldehyde concentrations were at or above the labelled concentrations; however, formaldehyde loss occurred with storage. NiSO4 particulate was uniformly distributed throughout the petrolatum. 'In-use' methyl methacrylate reagent syringes all contained ≤ 56% of the 2% label concentration, with no observable relationship with expiration date. Lower methyl methacrylate cocentrations were consistently measured at the syringe tip end, suggesting loss resulting from methyl methacrylate's volatility. The concentrations of glutaraldehyde patch test allergen preparations ranged from 27% to 45% of the labelled (1% in pet.) concentration, independently of expiration date. CONCLUSIONS: Some false-negative methyl methacrylate, formaldehyde or glutaraldehyde patch test results may be attributable to instability of the test preparations.

Hypersensitivity reactions to metallic implants - diagnostic algorithm and suggested patch test series for clinical use.

Cutaneous and systemic hypersensitivity reactions to implanted metals are challenging to evaluate and treat. Although they are uncommon, they do exist, and require appropriate and complete evaluation. This review summarizes the evidence regarding evaluation tools, especially patch and lymphocyte transformation tests, for hypersensitivity reactions to implanted metal devices. Patch test evaluation is the gold standard for metal hypersensitivity, although the results may be subjective. Regarding pre-implant testing, those patients with a reported history of metal dermatitis should be evaluated by patch testing. Those without a history of dermatitis should not be tested unless considerable concern exists. Regarding post-implant testing, a subset of patients with metal hypersensitivity may develop cutaneous or systemic reactions to implanted metals following implant. For symptomatic patients, a diagnostic algorithm to guide the selection of screening allergen series for patch testing is provided. At a minimum, an extended baseline screening series and metal screening is necessary. Static and dynamic orthopaedic implants, intravascular stent devices, implanted defibrillators and dental and gynaecological devices are considered. Basic management suggestions are provided. Our goal is to provide a comprehensive reference for use by those evaluating suspected cutaneous and systemic metal hypersensitivity reactions.

Shoe Allergens: A Retrospective Analysis of Cross-sectional Data From the North American Contact Dermatitis Group, 2005-2018.

BACKGROUND: Shoe contact allergy can be difficult to diagnose and manage. OBJECTIVE: The aim of the study was to characterize demographics, clinical characteristics, patch test results, and occupational data for the North American Contact Dermatitis Group patients with shoe contact allergy. METHODS: This is a retrospective study of 33,661 patients, patch tested from 2005 to 2018, with a shoe source, foot as 1 of 3 sites of dermatitis, and final primary diagnosis of allergic contact dermatitis. RESULTS: Three hundred fifty-two patients met the inclusion criteria. They were more likely to be male (odds ratio = 3.36, confidence interval = 2.71-4.17) and less likely to be older than 40 years (odds ratio = 0.49, confidence interval = 0.40-0.61) compared with others with positive patch test reactions. The most common relevant North American Contact Dermatitis Group screening allergens were potassium dichromate (29.8%), p-tert-butylphenol formaldehyde resin (20.1%), thiuram mix (13.3%), mixed dialkyl thioureas (12.6%), and carba mix (12%). A total of 29.8% (105/352) had positive patch test reactions to supplemental allergens, and 12.2% (43/352) only had reactions to supplemental allergens. CONCLUSIONS: Shoe contact allergy was more common in younger and male patients. Potassium dichromate and p-tert-butylphenol formaldehyde resin were the top shoe allergens. Testing supplemental allergens, personal care products, and shoe components should be part of a comprehensive evaluation of suspected shoe contact allergy.

Occupational Contact Dermatitis in Dental Personnel: A Retrospective Analysis of the North American Contact Dermatitis Group Data, 2001 to 2018.

BACKGROUND: Dental personnel are at risk of developing occupational contact dermatitis. OBJECTIVES: The aims of the study were to determine prevalence of occupational contact dermatitis in dental personnel referred for patch testing and to characterize relevant allergens and sources. METHODS: The study used a retrospective, cross-sectional analysis of the North American Contact Dermatitis Group (NACDG) data, 2001-2018. RESULTS: Of 41,109 patients, 585 (1.4%) were dental personnel. Dental personnel were significantly more likely than nondental personnel to be female (75.7% vs 67.4%, P < 0.0001), have occupationally related dermatitis (35.7% vs 11.5%, P < 0.0001), and/or have primary hand involvement (48.6% vs 22.5%, P < 0.0001). More than one quarter of dental personnel (62/585, 27.7%) had 1 or more occupationally related allergic patch test reaction(s). There were 249 occupationally related reactions to NACDG screening allergens, most commonly glutaraldehyde (18.1%), thiuram mix (16.1%), and carba mix (14.1%). The most common sources of NACDG screening allergens were gloves (30.7%), dental materials (26.6%), and sterilizing solutions (13.1%). Seventy-three dental personnel (12.5%) had 1 or more positive patch test reactions to occupationally related allergen(s)/substances not on the screening series. Occupationally related irritant contact dermatitis was identified in 22.2% (n = 130) of dental personnel, most commonly to nonskin soaps/detergents/disinfectants (32.0%). CONCLUSIONS: Occupational contact dermatitis is common in dental personnel referred for patch testing. Comprehensive testing beyond screening series is important in these patients.

Dermatitis in patients undergoing the Nuss procedure for correction of pectus excavatum.

BACKGROUND: The Nuss procedure was introduced in 1987 for the correction of pectus excavatum. In this procedure, a stainless steel bar is placed underneath the sternum. OBJECTIVES: To report cutaneous reactions associated with Nuss bar placement. METHODS: Over a period of 30 months, 50 patients underwent the Nuss procedure. The study population was limited to those who developed clinically significant cutaneous reactions postoperatively. Patient information was obtained from electronic medical records. All patients had been patch tested preoperatively with stainless steel discs supplied by the bar manufacturer. When performed, expanded patch testing was carried out in accordance with the North American Contact Dermatitis Group guidelines. RESULTS: Postoperatively, 3 patients developed areas of protuberant granulation tissue at one or more incision sites. One patient developed localized oedema, dermatitis, and lymphadenopathy. Two of these 4 patients underwent further patch testing. Of these 2, 1 with dermatitis had a positive reaction to nickel and the other, with granulation tissue, tested negative for metal allergy. CONCLUSIONS: Despite clinical evidence of cutaneous reactions or putative allergy, no patient required early removal of the bar(s). Cutaneous testing with stainless steel discs supplied by the bar manufacturer does not provide accurate screening for allergy to the implant used in the Nuss procedure.

Contact Dermatitis Associated With Nail Care Products: Retrospective Analysis of North American Contact Dermatitis Group Data, 2001-2016.

BACKGROUND: Ingredients in nail care products may lead to allergic and/or irritant contact dermatitis. OBJECTIVE: The aims of this study were to determine frequency of contact dermatitis associated with nail care products, characterize associated body sites, and describe causative allergens. METHODS: A retrospective analysis was conducted with the North American Contact Dermatitis Group data between 2001 and 2016. RESULTS: Of the 38,775 patients tested, 769 (2.0%) had: 1) more than 1 allergic patch test reaction associated with a nail care product (n = 746), 2) irritant contact dermatitis associated with a nail care product (n = 14), or 3) both (n = 9). Primary body sites included the face (43.0%) and hands (27.6%). The top 5 allergens were (2-hydroxyethyl methacrylate (273/482, 56.6%), methyl methacrylate (210/755, 27.8%), ethyl acrylate (190/755, 25.2%), ethyl-2-cyanoacrylate (12/175, 6.9%) and tosylamide (273/755, 36.2%). Frequency of allergy to 2-hydroxyethyl methacrylate (P = 0.0069) and ethyl acrylate (P = 0.0024) significantly increased over the study period, whereas allergy secondary to tosylamide significantly decreased (P < 0.0001). CONCLUSIONS: As long-lasting nail techniques become widespread, the prevalence of contact dermatitis to nail care products is expected to increase. Almost one-fifth of nail care product-associated allergens would have been missed without additional screening allergens beyond the North American Contact Dermatitis Group series, underscoring the need for testing to a broad array of allergens.

Hypersensitivity reactions associated with endovascular devices.

Allergic reactions to endoprostheses are uncommon and reported in association with orthopaedic, dental, endovascular and other implanted devices. Hypersensitivity reactions to the biomaterials used in endovascular prostheses are among the infrequent reactions that may lead to local or systemic complications following cardiovascular therapeutic interventions. This article reviews potential immunotoxic effects of commonly used biomaterials. Reports of putative hypersensitivity reactions to endovascular devices, including coronary stents, perforated foramen occluders, pacemakers and implantable cardioverter defibrillators are also reviewed.

Contact dermatitis of the hands: cross-sectional analyses of North American Contact Dermatitis Group Data, 1994-2004.

BACKGROUND: Hand dermatitis, including irritant and allergic contact dermatitis (ACD), is common. OBJECTIVE: To evaluate allergens, relevant irritants, sources and occupations associated with hand contact dermatitis using North American Contact Dermatitis Group (NACDG) data. METHODS: A cross-sectional analysis of 22,025 patients patch tested between 1994 and 2004. RESULTS: Hand involvement was found in 6953 patients; 959 had ACD as the only diagnosis. In these 959 patients, the 12 most frequent relevant allergens were quaternium-15 (16.5%), formaldehyde (13.0%), nickel sulfate (12.2%), fragrance mix (11.3%), thiuram mix (10.2%), balsam of Peru (9.6%), carba mix (7.8%), neomycin sulfate (7.7%), bacitracin (7.4%), methyldibromoglutaronitrile/phenoxyethanol 2.0% (7.4%), cobalt chloride (6.5%), and methyldibromoglutaronitrile/phenoxyethanol 2.5% (6.3%). Rubber allergens were most commonly associated with occupation. One third of patients with hand ACD had identifiable relevant irritants. LIMITATIONS: Cross-sectional analyses prevent evaluation of causal associations. CONCLUSION: In NACDG patients with hand ACD, the most common allergens included preservatives, metals, fragrances, topical antibiotics, and rubber additives.

Contact allergy to lidocaine: a report of sixteen cases.

Lidocaine is used widely as an injectable local anesthetic, occasionally as an intravenous drug for cardiac arrhythmias, and increasingly as a topical anesthetic. Reports of allergic contact dermatitis and delayed hypersensitivity reactions to this "amide" anesthetic are limited. We report 16 cases of lidocaine contact allergy seen over 5 years. Concomitant patch-test reactions occurred with neomycin 20% (10 cases), bacitracin 20% (9 cases), fragrance mix 8% (3 cases), balsam of Peru 25% (2 cases), and dibucaine 2.5% and benzocaine 5% (1 case each). Patch tests with lidocaine dilutions (in petrolatum) gave the following results: 10% (3 of 4 positive reactions), 5% (4 of 6 positive reactions), and 1% (3 of 6 positive reactions). Intradermal testing with lidocaine 1%, mepivacaine 2%, and bupivacaine 0.5% was performed on 8 patients, resulting in positive reactions to lidocaine in 3 patients and to mepivacaine in 1 patient. Bupivacaine yielded negative results in each of the 8 patients. Relevance of delayed reactions to injectable lidocaine was definite in 2 cases; past, probable, and unknown in 1 case each; and possible in 11 cases. Delayed hypersensitivity to lidocaine may present as "suture allergy," treatment failure, typical contact allergy, or other local skin or dental reactions. Allergen substitution is based on further patch and intradermal testing, the results of which may be discordant.

Shoe allergens: retrospective analysis of cross-sectional data from the north american contact dermatitis group, 2001-2004.

BACKGROUND: Chemicals used in leather tanning, rubber processing, and/or adhesives are the most often-cited culprits in footwear dermatitis. Patch testing patients with suspected shoe dermatitis is essential for diagnosis and management. OBJECTIVES: The four goals for this study were to (1) determine the frequency of allergens associated with a shoe source in North American Contact Dermatitis Group (NACDG) patients with footwear allergic contact dermatitis; (2) compare these results to allergen frequencies from other published studies; (3) quantify the number of shoe-related reactions that were not identified with the NACDG standard series; and (4) identify relevant allergens not included on the NACDG standard series, based on data from other published studies. METHODS: The NACDG patch-tested 10,061 patients between 2001 and 2004. Data were retrospectively analyzed by (1) allergen source coded as "shoe," (2) site of dermatitis as "feet," and (3) diagnosis of "allergic contact dermatitis." RESULTS: Among the 109 NACDG patients with allergic contact dermatitis (ACD) of the foot and a shoe source of allergens, p-tertiary butylphenol formaldehyde resin, an adhesive, was the most common allergen, accounting for 24.7% of positive patch-test results, followed by potassium dichromate (17.5%) and carba mix (11.7%). When the data were examined according to groups of allergens, rubber chemicals (40.4%) were the most frequent allergens, followed by adhesives (32.5%), and leather components (20.1%). When data from published studies were pooled, potassium dichromate (31.5%) was the most frequent allergen, followed by p-tertiary butylphenol formaldehyde resin (17.1%) and cobalt chloride (12.9%). NACDG patients were statistically more likely to have positive patch-test reactions to p-tertiary butylphenol formaldehyde resin and statistically less likely to have a positive patch-test reaction to potassium dichromate than patients represented in pooled data from past studies. Nineteen (17.4%) of the 109 NACDG patients with ACD of the foot and a shoe source of allergens were identified as having a shoe source of a relevant allergen not included in the NACDG standard series. CONCLUSIONS: In NACDG patients, the most common individual shoe allergen was p-tertiary butylphenol formaldehyde resin. As a group, rubber chemicals were most common, a finding consistent with those of other studies.

Allergic contact dermatitis to synthetic rubber gloves: changing trends in patch test reactions to accelerators.

BACKGROUND: Rubber gloves are one of the most frequent causes of occupational allergic contact dermatitis, especially in health care workers. OBSERVATIONS: We describe 23 patients with allergic contact dermatitis due to rubber accelerators in rubber gloves, some with disseminated dermatitis, treated during a 2-year period. Three had IgE-mediated latex allergies. Sixteen were health care workers from a single institution whose dermatitis was temporally related to the switch to latex-safe gloves. Each had positive patch test reactions to 1 or more rubber accelerators, including carbamates, thiurams, 2-mercaptobenzothiazole, and 1,3-diphenylguanidine. Chemical analysis of 6 glove samples identified 2-mercaptobenzothiazole in 4 and zinc diethyldithiocarbamate in 1. There were discordances between patch test results for glove chemicals and glove swatches and between available information on chemicals used during glove production and chemicals detected during glove analysis. Although these factors may complicate the search for culprit and alternative gloves, dermatitis cleared in each of 9 patients with follow-up data and for whom alternative gloves were provided based on published information of glove composition. CONCLUSIONS: Allergic contact dermatitis due to synthetic rubber gloves occurs even with the use of latex-safe products. More knowledge about chemicals present in these gloves, to which the skin is exposed during use, is necessary to prevent and treat allergic contact dermatitis.

Positivity ratio and reaction index: patch-test quality-control metrics applied to the north american contact dermatitis group database.

BACKGROUND: The positivity ratio (PR) and reaction index (RI) characterize the ability of patch-test preparations to produce strong (++ or +++) reactions as opposed to weak (+), questionable, or irritant reactions. OBJECTIVE: This study evaluates these measures for North American Contact Dermatitis Group (NACDG) patch-test preparations. METHODS: The PR and RI were calculated for 79 NACDG standard allergens tested from 1994 to 2006 (n = 26,479 patients). The median values were used as cutoff values for "acceptable" versus "problematic" preparations. RESULTS: The top 10 "acceptable" patch-test preparations (PR < or = 55 and RI > 0.46) were mixed dialkyl thioureas 1% in petrolatum (pet), tixocortol-21-pivalate 1% pet, ethylenediamine dihydrochloride 1% pet, sesquiterpene lactone mix 0.1% pet, nickel sulfate 2.5% pet, bacitracin 20% pet, thimerosal 0.1% pet, epoxy resin 1% pet, colophony 20% pet, and mercaptobenzothiazole 1% pet. The most "problematic" patch-test preparations (PR > 55 and RI < or = 0.46) were cocamidopropyl betaine 1% aqueous (aq), benzalkonium chloride 0.1% aq, jasmine absolute 2% pet, iodopropynyl butyl carbamate 0.1% pet, 2-bromo-2-nitropropane-1,3-diol 0.5% pet, methyldibromoglutaronitrile 0.4% pet, methyldibromoglutaronitrile/phenoxyethanol 2% pet and 2.5% pet, dimethylol dihydroxyethyleneurea 4.5% aq, and clobetasol-17-propionate 1% pet. CONCLUSION: Caution should be used when interpreting reactions to "problematic" patch-test preparations with a high proportion of weak, irritant, and questionable reactions.

Hand/face/neck localized pattern: sticky problems--resins.

Plastic resin systems have an increasingly diverse array of applications but also induce health hazards, the most common of which are allergic and irritant contact dermatitis. Contact urticaria, pigmentary changes, and photoallergic contact dermatitis may occasionally occur. Other health effects, especially respiratory and neurologic signs and symptoms, have also been reported. These resin systems include epoxies, the most frequent synthetic resin systems to cause contact dermatitis, (meth)acrylics, polyurethanes, phenol-formaldehydes, polyesters, amino resins (melamine-formaldehydes, urea-formaldehydes), polyvinyls, polystyrenes, polyolefins, polyamides and polycarbonates. Contact dermatitis usually occurs as a result of exposure to the monomers and additives in the occupational setting, although reports from consumers, using the raw materials or end products periodically surface. Resin- and additive-induced direct contact dermatitis usually presents on the hands, fingers, and forearms, while facial, eyelid, and neck involvement may occur through indirect contact, eg, via the hands, or from airborne exposure. Patch testing with commercially available materials, and in some cases the patient's own resins, is important for diagnosis. Industrial hygiene prevention techniques are essential to reduce contact dermatitis when handling these resin systems.

Contact dermatitis from acrylics in a histology laboratory assistant.

The use of acrylics has expanded enormously, resulting in a vast range of products for both occupational and non-occupational purposes. Acrylics reported to cause allergic contact dermatitis in histology technicians are 2-hydroxyethyl methacrylate and 2-hydroxyethel acrylate.

Contact dermatitis in the bowling pro shop.

A 29-year-old bowling pro shop operator presented with recurrent disseminated erythematous and edematous patches and plaques. Patch-testing with the North American Contact Dermatitis Group (NACDG) standard series yielded ++ and + reactions to epoxy resin at 2 and 7 days, respectively. We could find no other report of epoxy resin contact allergy in a bowling pro shop operator.

Positive patch-test reactions to mixed dialkyl thioureas: cross-sectional data from the North American Contact Dermatitis Group, 1994 to 2004.

BACKGROUND: Allergic contact dermatitis from thioureas is uncommon but may result from exposure to rubber, especially neoprene. OBJECTIVES: To (1) describe the population with positive patch-test reactions to mixed dialkyl thioureas (MDTU) (ie, diethylthiourea and dibutylthiourea); (2) determine clinical and occupational relevance associated with reactions to MDTU and identify the most commonly related sources and occupations; and (3) examine the frequency of co-reacting allergens in MDTU-positive patients. METHODS: A retrospective analysis of cross-sectional data of 22,025 patients patch-tested by the North American Contact Dermatitis Group between 1994 and 2004. RESULTS: Of 21,898 patients tested with MDTU, 225 (1.0%) had positive reactions; of these, 173 (76.9%) were currently relevant and 29 (17.1%) were occupationally relevant. Patients positive to MDTU were 2.6 times more likely to have foot involvement than patients with positive reactions to other allergens (p < .0001). Footwear was the most commonly identified source overall (20.0%) whereas gloves were the most common occupational source. Of the 173 patients with currently relevant MDTU reactions, 24.9% also reacted to another rubber allergen. CONCLUSIONS: Current clinical relevance of reactions to MDTU was high; occupational relevance was less frequent. Patch tests with common rubber allergens (carbamates, thiurams, and mercaptobenzothiazole) may fail to detect many cases of thiourea-induced rubber allergic contact dermatitis.

Contact dermatitis to a limb prosthesis.

PROSTHESIS USERS commonly develop various skin problems on the residual limb, directly under the prosthetic device when the device is in direct contact with the skin. Prolonged occlusion and humidity increase the likelihood of developing contact sensitivity to moisturizing creams, medicaments, and materials in the prosthesis itself.1 Allergic contact dermatitis to various prosthetic design materials is uncommon, and the relevance of positive patch-test results to chemicals present in prostheses may be difficult to establish. Most reports of allergic contact dermatitis to prostheses have been concerned with surgical amputees and not congenital amputees. We report a 5-year-old boy with a transverse partial hemimelia who developed allergic contact dermatitis to an adhesive used in his myoelectric prosthesis. Unlike most prostheses, myoelectric prostheses are worn directly against the skin, for surface electromyography electrode contact.