Metal implant allergy: A retrospective cohort analysis at a university allergy practice.

Background: Concern of metal sensitization in pre- and postsurgical evaluation is growing, with the recent guidelines remaining the criterion standard for consideration of patch testing. Information remains scarce on surgical screening in the groups of patients who reported a history of metal sensitivity versus those with no reported history. Objective: The objective of this study was to assess the utility of patch testing in surgical candidates based on reported metal allergy history. The secondary objective was to evaluate the utility and outcomes in postsurgical patch testing. Methods: Nine hundred and thirty-one patient charts of patients with the diagnosis of "contact dermatitis" who underwent an evaluation at a single allergy clinic site between January 2013 and December 2022 were identified and reviewed as part of a retrospective chart review study. Patients were included in subgroups based on the time of patch testing and history of reported metal allergy. Results: In all, 67 patients underwent patch testing, 10 (14.9%) of whom were surgical candidates without a history of metal sensitivity, 31 (46.2%) of whom were surgical candidates with a history of metal sensitivity, and 26 (38.8%) of whom were postsurgical patients. Twenty-nine (43.3%) of patients had positive patch testing results, with only one (10%) in the presurgical group, 17 (54.8%) in the presurgical with a history of metal sensitivity, and 11 (42.3%) in the postsurgical group. Zero patients in our cohort without metal sensitivity who were undergoing the Nuss procedure had positive reactions on patch testing, whereas two of four (50%) with reported metal sensitivity who were undergoing the Nuss procedure had positive relevant metal reactions. Conclusion: Ambiguity in the utility of patch testing for surgical decision making remains, despite common utilization. Recent guidelines along with coordination of care among the surgeon, allergist, and patient remains the criterion standard of care.

Patch test in Brazilian children with a clinical diagnosis of atopic dermatitis: a cross-sectional study using an extended patch test battery.

INTRODUCTION: Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease mainly affecting children. Similarly, Allergic contact dermatitis (ACD) is an inflammatory skin disease, but unlike AD it results from direct exposure to an external agent. Theoretically, the impaired skin barrier facilitates the penetration of potential allergens. Therefore, AD patients are at risk for an associated ACD, exacerbating their skin condition. Because eczema is similar, performing a patch test (PT) for the differential diagnosis is essential. METHODS: In this cross-sectional transversal study, we performed a PT with 30 sensitizers in 26 children with AD, selected according to established criteria for suspected ACD, and treated at an AD center of a pediatric university hospital in Rio de Janeiro. Clinical presentation, patient profile, main sensitizers, and frequency of ACD caused by therapeutic skincare products were evaluated. RESULTS: In all, 23 (88.5%) patients reacted to at least one allergen, 21 (80.7%) had a relevant positive patch test, and 15 (57.7%) were polysensitized. The main positive sensitizers were nickel (38.5%), blue disperse (30.8%), fragrance mix (30.8%), and neomycin (23.1%). Nineteen (73%) patients reacted to substances present in therapeutic or skincare products. CONCLUSION: Our data underscore the importance of performing a PT in AD children whose eczema has atypical distribution. The expressive percentage of positive tests, especially of allergens in skincare products, indicates the constant need to review the proposed treatments. Therefore, we recommend a specific and expanded PT battery for pediatric AD patients, including a negative control, to increase sensitivity for diagnosing ACD.

The new Italian SIDAPA Baseline Series for patch testing (2023): an update according to the new regulatory pathway for contact allergens.

Allergic contact dermatitis (ACD) is a common inflammatory skin disease caused by delayed hypersensitivity to chemical and biotic contact allergens. ACD significantly affects the patients' quality of life negatively impacting both occupational and non-occupational settings. Patch testing is the gold standard diagnostic in vivo test to precise the ACD etiology and to correctly perform prevention. According to the Italian Medicines Agency (AIFA) legislative decree no. 178 of 29th May 1991, allergens are defined as medicines and therefore they are subject to strict regulation. In 2017, AIFA (decree no. 2130/2017) started a procedure to regulate contact allergens on the Italian market and actually the contact allergens temporarily authorized are reported in AIFA decree no. 98/2022, valid until November 2023. The availability on the market of contact allergens to diagnose ACD and continuous updating on the basis of new epidemiological trends are mandatory, jointly with the continuous update of the baseline and integrative series for patch testing. For this reason, the scientific community represented in Italy by the Skin Allergies Study Group of SIDeMaST (Italian Society of Dermatology and Venereology) and SIDAPA (Italian Society of Allergological, Occupational and Environmental Dermatology) are constantly working, in close relationship with the European scientific communities with large expertise in this important sector of the modern Dermatology. Herein, we report the setting up of regulatory legislation by AIFA and the new Italian Adult Baseline Series for patch testing.

2-Cyanoethyl dimethyldithiocarbamate, a new contact allergen found in accelerator-free nitrile gloves.

BACKGROUND: Allergic contact dermatitis (ACD) from rubber glove usage is usually caused by rubber additives such as the accelerators. However, in analyses of the suspected gloves, ordinary rubber allergens are not always found. Accelerator-free rubber gloves are available, but some patients with accelerator allergy do not tolerate them and might also be patch test positive to them. OBJECTIVES: To identify and chemically characterize a new allergen, 2-cyanoethyl dimethyldithiocarbamate (CEDMC), in rubber gloves. We describe two patient cases: patient 1 that led us to the identification of CEDMC and patient 2 with occupational ACD caused by CEDMC. METHODS: The patients were examined with patch testing including baseline and rubber series, and their own rubber gloves. High-performance liquid chromatography (HPLC) was used for chemical analysis of rubber gloves. The allergen was synthesized and identified by nuclear magnetic resonance, mass spectrometry and infrared spectrometry, and tested on patient 2. RESULTS: CEDMC was identified by HPLC in a nitrile glove associated with hand eczema in patient 1. Patient 2 whose nitrile gloves contained CEDMC was patch test positive to CEDMC. CONCLUSIONS: CEDMC is a new contact allergen in nitrile gloves and probably forms during vulcanization from residual monomer acrylonitrile and rubber additives.

[Translated article] Allergic Contact Dermatitis to Topical Ophthalmic Drugs: Review of Frequently Used Allergens in Spain.

Allergic contact dermatitis induced by the use of ophthalmic topical drugs is one of the most common causes of eyelid dermatitis. The introduction of new formulations, both of active ingredients and excipients, and the lack of marketing in some of them, makes patch testing in patients whose source of contact are topical ophthalmic drugs truly challenging. Across this manuscript, most, if not all, topical ophthalmic drugs used in our national health system have been collected, including information on the allergens available, and the concentration and vehicle advised for those that still remain unavailable.

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

BACKGROUND: Psoriasis 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. OBJECTIVES: To 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. METHODS: Cross-sectional study with data from REIDAC from 2018 through 2023 of selected patients with a diagnosis of psoriasis and/or ACD. RESULTS: A 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. CONCLUSIONS: Overall, 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.

Less efficient skin penetration of the metal allergen Pd2+ compared to Ni2+ and Co2+ from patch test preparations.

BACKGROUND: Contrary to Ni2+- and Co2+-induced allergic contact dermatitis (ACD), reactions against Pd2+ are rare. However, Pd2+ activates a larger T cell fraction in vitro, suggesting an inefficient skin penetration. OBJECTIVES: This study compares Ni2+, Co2+ and Pd2+ skin penetration from commonly used diagnostic patch test preparations (PTPs) and aqueous metal salt solutions. METHODS: Using Franz diffusion cell assays, we applied the metals in PTPs (5% NiSO4, 1% CoCl2, 2% PdCl2 and 3% Na2PdCl4) and in solution to pigskin for 48 h, thereby mirroring the time frame of a patch test. The different compartments were analysed individually by inductively coupled plasma mass spectrometry. RESULTS: Metal ions were mainly retained in the upper stratum corneum layers. After application of PTPs, concentrations in the viable skin were lower for Pd2+ (1 and 7 µM) compared to Ni2+ and Co2+ (54 and 17 µM). CONCLUSIONS: Ni2+ and Co2+ penetrated the skin more efficiently than Pd2+ and thus may sensitize and elicit ACD more easily. This was observed for ions applied in petrolatum and aqueous solutions. We hypothesize that the differently charged metal complexes are responsible for the varying skin penetration behaviours.

Tangled Truths: Unraveling the Link Between Frontal Fibrosing Alopecia and Allergic Contact Dermatitis.

Frontal fibrosing alopecia (FFA) is an increasingly common diagnosis, especially in middle-aged women, and has garnered growing attention in the scientific literature. This variant of lichen planopilaris (LPP) is recognized as a progressive scarring alopecia affecting the frontal and temporal regions of the scalp as well as the eyebrows and occasionally other sites. Although its precise etiology remains elusive, various factors such as genetics, medications, hormonal influences, and environmental exposures-including specific chemicals present in sunscreens-have been implicated in its pathogenesis but without evidence of causality. The potential relationship between contact allergy and FFA has been explored, with some suggesting an increased prevalence of contact allergy among patients diagnosed with FFA. This article aims to explore the potential association between contact allergy and FFA, focusing on the current published literature and implicated allergens.

Subclinical immune responses to nickel in sensitized individuals-a dose-response study.

BACKGROUND: Nickel is the leading cause of contact allergy in Europe, with 14.5% of the adult population being sensitized. Despite regulations limiting nickel release from consumer items, the incidence and prevalence of nickel allergy remain high. OBJECTIVE: To investigate the clinical and subclinical immune response to low-dose nickel exposure on nickel pre-exposed skin to assess the adequacy of current regulatory limits. METHOD: Nickel-allergic and healthy controls were patch tested with nickel twice with a 3-4 weeks interval. The first exposure used the diagnostic concentration of 2000 µg/cm2 nickel sulphate, and the same skin areas were then re-exposed to 0.2, 0.5, 12.8 and 370 µg/cm2 nickel sulphate. After 48 h, the patch reactions were examined for clinical signs of eczema, and skin biopsies were collected. The transcriptomic immune profile was analysed with Nanostring nCounter and quantitative polymerase chain reaction. RESULTS: Two nickel-allergic participants (15%) had clinical reactions to the regulatory limiting doses for nickel (0.2/0.5 µg/cm2) following re-exposure. There was immune activation in all skin areas following re-exposure to nickel, predominantly mediated by up-regulation of cytokines and chemokines. In all nickel re-exposed skin areas, 81 genes were up-regulated independent from the clinical response. In skin areas exposed to 0.2 µg/cm2, 101 immune-related genes were differentially expressed, even when no clinical response was observed. Healthy controls showed up-regulation of three genes in response to nickel re-exposures without any clinical reactions. CONCLUSION: Immune activation can be induced in skin with local memory to nickel upon challenge with nickel doses within the regulatory limits. Our findings suggest that the regulatory limits in the European nickel regulation may not provide sufficient protection for consumers against low-dose exposures.

Patch Testing in Allergic Contact Dermatitis.

BACKGROUND: Allergic contact dermatitis is one of the most common forms of skin diseases that require medical intervention. Appropriate detection of allergens by patch test and accurate avoidance of them is the key to management. The objective of this study is to determine the types and frequency of allergens responsible for Allergic contact dermatitis in a tertiary hospital of Nepal. METHODS: Altogether 120 patients with Allergic contact dermatitis were enrolled in the study. Patch test was performed to find out the most common inciting allergen, utilizing the Indian Standard Series of allergens approved by The Contact and Occupational Dermatoses Forum of India. Results were read at 48 and 96 hours. Grading of the reactions was done based on the criteria of the International Contact Dermatitis Research Group. Pattern of reactivity of different allergens was assessed. RESULTS: Of all the patients, 63 (53%) showed positivity to at least one allergen. Nickel sulfate was the most frequent sensitizing agent in 22 (18%) cases, followed by Fragrance mix in 11(9%) and Paraphenylenediamine in 7 (6%) cases. Out of all positive results, Grade 1 positivity was seen in 44 (51%), Grade 2 positivity in 41(47%) and only 2 (2%) cases showed Grade 3 positivity. Mercaptobenzothiazole, Balsam of Peru, Nitrofurazone and Wool Alcohol did not show positive results in any of our patients. CONCLUSIONS: Patch testing helps in the treatment, long term remission, and patient counseling for prevention. Larger scale studies are required to know the sensitivity to allergens in Nepalese population.

Contact Allergy to Allergens in the Swedish Baseline Series Overrepresented in Diabetes Patients with Skin Reactions to Medical Devices - A Retrospective Study from Southern Sweden.

Allergic contact dermatitis is reported among individuals using continuous glucose monitoring systems and insulin pumps. The aim of this study was to describe contact allergy patterns for allergens in the Swedish baseline series and medical device-related allergens among users. Contact allergy to baseline series allergens and isobornyl acrylate was compared between diabetes patients and dermatitis patients patch-tested at the Department of Occupational and Environmental Dermatology during 2017 to 2020. Fifty- four diabetes patients and 2,567 dermatitis patients were included. The prevalence of contact allergy to fragrance mix II and sesquiterpene lactone mix was significantly higher in diabetes patients compared with dermatitis patients. Of the diabetes patients 13.0% and of the dermatitis patients 0.5% tested positive to sesquiterpene lactone mix (p < 0.001). Of the diabetes patients 7.4% and of the dermatitis patients 2.3% tested positive to fragrance mix II (p = 0.041). Of the diabetes patients 70.4% tested positive to medical device-related allergens. Of the diabetes patients 63.0% and of the dermatitis patients 0.2% were allergic to isobornyl acrylate (p < 0.001). In conclusion, not only medical device-related contact allergies, but also contact allergy to baseline series allergens (fragrance mix II and sesquiterpene lactone mix), is overrepresented in diabetes patients who use medical devices.