Carola Lidén

European Society of Contact Dermatitis guideline for diagnostic patch testing – recommendations on best practice

The present guideline summarizes all aspects of patch testing for the diagnosis of contact allergy in patients suspected of suffering, or having been suffering, from allergic contact dermatitis or other delayed‐type hypersensitivity skin and mucosal conditions. Sections with brief descriptions and discussions of different pertinent topics are followed by a highlighted short practical recommendation. Topics comprise, after an introduction with important definitions, materials, technique, modifications of epicutaneous testing, individual factors influencing the patch test outcome or necessitating special considerations, children, patients with occupational contact dermatitis and drug eruptions as special groups, patch testing of materials brought in by the patient, adverse effects of patch testing, and the final evaluation and patient counselling based on this judgement. Finally, short reference is made to aspects of (continuing) medical education and to electronic collection of data for epidemiological surveillance.

Evaluation of the skin sensitizing potency of chemicals by using the existing methods and considerations of relevance for elicitation

The Technical Committee of Classification and Labelling dealing with harmonized classification of substances and classification criteria under Directive 67/548/EEC on behalf of the European Commission nominated an expert group on skin sensitization in order to investigate further the possibility for potency consideration of skin sensitizers for future development of the classification criteria. All substances and preparations should be classified on the basis of their intrinsic properties and should be labelled accordingly with the rules set up in the Directive 67/548/EEC. The classification should be the same under their full life cycle and in the case that there is no harmonized classification the substance or preparation should be self‐classified by the manufacturer in accordance with the same criteria. The Directive does not apply to certain preparations in the finished state, such as medical products, cosmetics, food and feeding stuffs, which are subject to specific community legislation. The main questions that are answered in this report are whether it would be possible to give detailed guidance on how to grade allergen potency based on the existing methods, whether such grading could be translated into practical thresholds and whether these could be set for both induction and elicitation. Examples are given for substances falling into various potency groups for skin sensitization relating to results from the local lymph node assay, the guinea pig maximization test, the Buehler method and human experience.

Preservatives and fragrances in selected consumer-available cosmetics and detergents

Background. Preservatives and fragrances are important and frequent skin sensitizers, found in a wide range of products intended for personal and occupational use.

Self-diagnosed dermatitis in adults. Results from a population survey in Stockholm.

In a population‐based survey of public health issues in Stockholm, Sweden, self‐reported hand eczema, history of childhood eczema, nickel allergy, occurrence of skin symptoms on the face and intolerance to cosmetics and hygiene products, were investigated. A postal questionnaire was sent to 15,000 inhabitants aged 19–80 years. The response rate was 73%. The 1‐year prevalence of hand eczema was 8% (females 10%, males 6%). History of childhood eczema was reported by 15% and, of these, 42% also stated positively that they had had hand eczema at some time. Hypersensitivity to nickel was owned to 15% of the females and 3% of the males. Of the nickel‐sensitive, 30% reported ever having had hand eczema. The combination of nickel allergy and history of childhood eczema resulted in a cumulative prevalence of hand eczema of 56%. Females reported more hand‐washings per day than did males, and a relation between number of hand‐washings and hand eczema was found. Self‐reported 1‐year prevalence of skin symptoms on the face was 14% and, of these, 33% also owned to hypersensitivity to cosmetics. Dermatitis appears to be a common health problem. This fact should be made clear to those who give priority and allocate resources to health problems, e.g., by participation of dermatologists in performing population‐based surveys.

Nickel on the Swedish market. Follow-up after implementation of the Nickel Directive.

The Nickel Directive aims at the prevention of sensitization and elicitation of nickel dermatitis. It limits nickel release from, and nickel content in, certain items. The Directive came into full force by July 2001. The aim of this study was to investigate the frequency on the market of items that release nickel and of nickel content in piercing posts, 2 years after coming into force of the Directive. Of special interest was to study changes compared to the situation in 1999, when a baseline study had been carried out. Nickel release from 786 items covered by the Nickel Directive was tested with the dimethylglyoxime (DMG) test, and nickel content in 18 piercing posts was analysed. Nickel release was shown from 8% of items intended for direct and prolonged contact with the skin, and 17% of the piercing posts contained too much nickel, a decrease compared to 1999. There has been significant adaptation to the requirements of the Nickel Directive. The DMG test is useful for screening for nickel release and for monitoring the market. Provided there is further adaptation to the requirements, the risk of sensitization and elicitation of nickel dermatitis will be significantly reduced.

Nickel release from coins

Nickel allergy is the most frequent contact allergy and is also one of the major background factors for hand eczema. The clinical significance of nickel release from coins was discussed when the composition of euro coins was decided. Current European coinage is dominated by cupro‐nickel coins (Cu 75; Ni 25); other nickel‐containing and non‐nickel alloys are also used. Nickel release from used coinage from the UK, Sweden and France was determined. It was shown that nickel ions are readily available on the surface of used coins. After 2 min in artificial sweat, approximately 2 μg of nickel per coin was extracted from cupro‐nickel coins. Less nickel was extracted from non‐nickel coins. Nickel on the surface was mainly present as chloride. After 1 week in artificial sweat approximately 30 μg/cm2 was released from cupro‐nickel coins: less nickel was released from coins made of other nickel alloys. Theoretically, several μg of nickel salts may be transferred daily onto hands by intense handling of high‐nickel‐releasing coins.

Nickel release from tools on the Swedish market

Nickel allergy in women has been thoroughly studied: its prevalence, the most important sources of sensitization, and risk factors for elicitation of dermatitis. Preventive measures have also been introduced. Nickel allergy in men has not, however, been equally focused on. Based on clinical experience, some publications indicating that tools may be a risk factor for nickel allergy and hand eczema in men, and the fact that large occupational groups regularly use tools, we decided to carry out a study, of the prevalence on the market of tools that release nickel. 27% of 565 hand‐held tools with metal parts that come into contact with the skin were found to be dimethylglyoxime (DMG) test positive. Release of nickel and other metals into artificial sweat and composition of metals on the surface and in the base alloy were also studied. It is suggested that tool producers should consider nickel allergy and avoid nickel‐releasing materials, and that analytical methods, relevant for nickel release from tools, should be further developed.

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.

The EU Nickel Directive revisited—future steps towards better protection against nickel allergy

In July 2001, the EU Nickel Directive came into full force to protect European citizens against nickel allergy and dermatitis. Prior to this intervention, Northern European governments had already begun to regulate consumer nickel exposure. According to part 2 of the EU Nickel Directive and the Danish nickel regulation, consumer items intended to be in direct and prolonged contact with the skin were not allowed to release more than 0.5 µg nickel/cm2/week. It was considered unlikely that nickel allergy would disappear altogether as a proportion of individuals reacted below the level defined by the EU Nickel Directive. Despite this, the EU Nickel Directive part 2 was expected to work as an operational limit that would sufficiently protect European consumers against nickel allergy and dermatitis. This review presents the accumulation of epidemiological studies that evaluated the possible effect of this major public health intervention. Also, it evaluates recent exposure assessment studies that have been performed using the dimethyl glyoxime test. It is concluded that the EU Nickel Directive has started to change the epidemiology of nickel allergy in Europe but it should be revisited to better protect consumers and workers since nickel allergy and dermatitis remain very frequent.

Deposition of nickel, chromium, and cobalt on the skin in some occupations – assessment by acid wipe sampling

Background:  Nickel, chromium, and cobalt are important skin sensitizers. Better knowledge about skin exposure is needed for more efficient prevention. We have previously developed acid wipe sampling for assessment of skin exposure to metals.