Jakob Dahlin

A positive cobalt spot test falsely indicating an occupational allergic contact dermatitis caused by cobalt.

For investigation of chemical exposure in allergic individuals, spot tests are invaluable. A reagent may react with a specific compound to give a specific typical colour, and thus indicate the presence of the specific substance. Spot tests can give both false‐negative and false‐positive reactions. To confirm the presence of the substance and quantify it, more sophisticated methods are required. On the basis of a positive cobalt spot test result, a woman was initially diagnosed with an occupational allergic contact dermatitis caused by cobalt.

Several cases of undesirable effects caused by methacrylate ultraviolet-curing nail polish for non-professional use.

Ultraviolet (UV)‐curing nail polishes based on acrylates or methacrylates are currently also available for non‐professional use. The Swedish Medical Products Agency recently prohibited one brand of UV‐curing polish, because several consumers reported undesirable effects after using it.

Implants and contact allergy: are sensitizing metals released as haptens from coronary stents?

The possible impact of metal release from coronary artery stents has, with their increased use, become a concern.

Allergic contact dermatitis caused by nickel in a green eye pencil.

A 47-year-old non-atopic woman, intolerant of costume jewellery, was referred for patch-testing to the Contact Allergy Unit in Leuven with a 4-month history of itching, erythema, moderate infiltration and scaling of both eyelids, which she attributed to the use of eye make-up products. Her symptoms resolved during a 1-month vacation in Africa, where she did not use any make-up, but recurred following her return. Patch tests were performed with the baseline (Trolab, Hermal, Reinbeck, Germany) and cosmetic series, as well as the patient’s own products and topical medicaments, using Van der Bend patch test chambers (Van der Bend, Brielle, The Netherlands). Positive reactions were observed to nickel (+ at D4) and the Deborah® green eye pencil (Deborah, SpA, Milano, Italy) (+ at D2 and D4) (Fig. 1) only. At follow-up of this patient, the lesions had disappeared completely after avoidance of the eye pencil. Chemical analysis of the Deborah® green eye pencil was performed in Malmö, by dissolving about 240 mg of the colour in dichloromethane by shaking. After a few minutes a green insoluble precipitate was

Triphenylguanidine, a new (old?) rubber accelerator detected in surgical gloves that may cause allergic contact dermatitis.

Rubber accelerators are common contact allergens in healthcare personnel, owing to exposures from medical gloves.

Hidden exposure to formaldehyde in a swab caused allergic contact dermatitis

Octocrylene is an ultraviolet (UV)B and UVAII absorber that was introduced some 15 years ago, and is now widely used in sunscreen agents and skin care cosmetics. Since 2003, several studies, notably from France, Belgium, Spain, and Italy, have reported an increasing number of patients with photocontact allergy to octocrylene. This reaction is seen mainly in adult patients who have previously used topical products containing the non-steroidal anti-inflammatory drug ketoprofen. Photosensitization to ketoprofen leads, in many cases, to photocontact allergy to octocrylene; the mechanism of this reaction is unknown. Contact allergy to octocrylene also occurs, but is far less frequent, and is seen, in most cases, in children, resulting from the use of octocrylene-containing sunscreen products. In this article, (photo)contact allergy to octocrylene is fully reviewed.

No contact allergy to acrylic acid and methacrylic acid in routinely tested dermatitis patients

Occupational and non-occupational contact allergy to, and allergic contact dermatitis caused by, acrylates/methacrylates are frequently reported (1–18). However, there is no acrylate/methacrylate test preparation in the European baseline patch test series (19). Therefore, contact allergy to, and allergic contact dermatitis caused by, acrylates/methacrylates may be overlooked when the decision is made on what to patch test with in diagnostic work-up of dermatitis patients (5). There are many sensitizing acrylates/methacrylates to consider regarding whether an acrylate/methacrylate preparation should be included in the European baseline patch test series. Therefore, patch testing with a mix of the acrylates/methacrylates with the highest contact allergy rates when they are routinely tested has been tried, but has been unsuccessful (7). Recently, an Italian article reported contamination with acrylic acid in an electrode gel to be the likely cause of the allergic contact dermatitis (18). The patient reacted positively to a few methacrylates not present in the gel, and these were interpreted as cross-reactions. At least theoretically, acrylic acid and methacrylic acid could be formed by the hydrolysis of acrylates and methacrylates in the skin. Therefore, the acids could be major possible hapten(s) concerning contact allergy to acrylates/methacrylates. To test this hypothesis, in this study the acids were routinely tested in dermatitis patients.

Chemical burns caused by trifluoroacetic acid

Trifluoroacetic acid is a very strong carboxylic acid. The acid has been suspected to have similar toxic effects as hydrofluoric acid on skin contact. Hydrofluoric acid is highly toxic, owing to skin penetration by fluoride ions. A spill of hydrofluoric acid on the skin may be fatal. As trifluoroacetic acid contains fluorine, patients with chemical burns caused by trifluoroacetic acid have been given particular attention when treated in the hospital.

Quantification of l-carvone in toothpastes available on the Swedish market

Toothpastes have widespread use in the population, and contain flavours to give a pleasant and often minty aroma. Flavours are prevalent allergens in toothpastes, and adverse reactions often present as perioral dermatitis or stomatitis. l‐Carvone, a mint flavour found in spearmint oil, is one of these allergens. There are few studies on contact allergy to l‐carvone, and some of them have indicated a positive relationship with oral lichenoid lesions.

What lash stylists and dermatologists should know

In the last few years it has become popular to have eyelashes extended by the use of glue-on silk lashes. Extension is performed by a lash stylist, who mounts artificial eyelashes, one by one or up to four at a time, on each hair of the eyelash, using ethyl cyanoacrylate-based glue. To protect the delicate skin below the eyes and also to hold down the lower lashes, a pad is usually placed below the eye on each side of this area and secured with tape. So-called gel pads are supposed to increase comfort during treatment, and the surface facing the skin contains a gel that, according to the producer, should cool the skin. Several brands of gel pads used in Sweden are used with gels containing the preservative methylisothiazolinone (MI) (CAS no. 2682-20-4). As the process of lash extension may take several hours, depending on the number of lashes to be glued, the use of gel pads may lead to allergic contact dermatitis if the customer is allergic to MI.