Kumiko Washizaki

Quantitative evaluation of patch test reactions: a comparison between visual grading and erythema index image analysis

Background/aims: The interpretation of patch test reactions may vary between examiners. As test results are graded, an issue also arises when differing degrees of erythema are placed in the same grade. The purpose of this study was to quantitatively evaluate the degree of erythema in patch tests using image analysis and to study the usefulness of this method by comparing it with visual grading.

Optimal patch application time in the evaluation of skin irritation

We investigated the optimum application for evaluating skin irritation response by using samples of irritants commonly used as additives in cosmetics and other common household products. We studied 47 volunteers (16 men and 31 women). We selected three types of surfactant, one moisturizer, one anti‐infective agent and one oil solution. Using Finn chambers on Scanpor tape, we performed the patch test. A total of 0.015 mL of each sample was applied to the Finn chamber. For liquids, circular filter paper was soaked in 0.015 mL of the sample. Samples were placed on the upper back of participants, and closed for 4, 24 or 48 h. A patch application time of 24 h is sufficient to detect primary skin irritation from irritants in cosmetics and other common household products. In addition, we found that skin irritation reactions were strongest at 24 h after patch removal and that the reaction tended to be weaker at 48 h after patch removal. Patch testing to evaluate irritants should be performed by means of a 24‐h patch test with a follow‐up reading at 24 h after patch removal. An application time of 24 h places less of a burden on patients than a 48‐h patch test.

A case of allergic contact dermatitis to polyglyceryl laurate

An 80-year-old woman experienced recurring pruritic erythema on her face for 3 months. She was treated with steroid ointment, but her condition gradually became worse, and she therefore visited our hospital on 10 February 2005. We suspected contact dermatitis. Using Finn Chamber (Epitest Ltd Oy, Tuusula, Finland) and Scanpor tape (Alpharma AS, Norgesplaster Facility, Vennesla, Norway), we performed 48-hr closed patch testing with the cosmetics that she had been using. Readings were made at 1 hr and 1 D after removal according to International Contact Dermatitis Research Group (ICDRG) recommendations. She showed a positive reaction (þþ) to the essential gel (as is). Further patch testing was performed with all ingredients of the essential gel. She exhibited a positive reaction (þ) to polyglyceryl-10 laurate 0.5%aq., and this positive reaction remained positive after 7 days. A 3rd patch test was performed with polyglyceryl-10 laurate (1%, 0.5%, 0.1%, and 0.05%aq.), and she exhibited positive reactions (þ) to all concentrations tested. After 6 months, a 4th patch test was performed using polyglyceryl laurate produced by several manufacturers, as we did not know which manufacturer produced the polyglyceryl-10 laurate in the essential gel the patient had been using. She showed positive reactions (þ) to polyglyceryl-10 laurate from manufacturer A, manufacturer B (1%, 0.5%, 0.05%, and 0.01%aq.) and polyglyceryl-10 laurate from manufacturer C (1% and 0.5%aq.). We then performed patch testing with polyglyceryl-4 laurate and polyglyceryl-6 laurate from manufacturer C (1% and 0.5%aq.), and she exhibited positive reactions (þ) to both as well. She exhibited negative reactions to polyglyceryl-10 myristate, polyglyceryl-10 isostearate, polyglyceryl-10 stearate, and polyglyceryl-10 oleate (1%, 0.5%, 0.05%, and 0.01%aq). The 7 control materials tested gave negative reactions. The dermatitis cleared after the patient ceased using the essential gel. We thus concluded that our patient had developed allergic contact dermatitis against the polyglyceryl laurate present in the essential gel.

A multi-institutional joint study of contact dermatitis related to hair colouring and perming agents in Japan

In Japan, allergic contact dermatitis caused by hair colouring agents is a considerable problem for those occupationally exposed and also for consumers. Over the last 20 years, p‐phenylenediamine (PPD) has been a common allergen, with ∼7% positive patch test reactions.

A case of allergic contact dermatitis caused by glucan oligosaccharide.

A 32-year-old woman presented with a 1-day history of an acute dermatitis on her face. She had changed her skin lotion 3 days previously. The patient had had a previous episode of dermatitis causedbya cosmetic, and this also contained glucan oligosaccharide. She was patch tested with the cosmetics that she had been using [2-day occlusion using Finn Chamber (Epitest Ltd Oy, Tuusula, Finland) on Scanpor tape (Alpharma AS, Norway)]. Readings were taken on D2, D3 andD6, according to International Contact Dermatitis Research Group recommendations. There was a positive reaction (þþ) to the skin lotion ‘as is’. Further patch testing was performed with all ingredients of this skin lotion andwith the lotionwith reduced levels of glucan oligosaccharide. There was a positive reaction (þ) to glucan oligosaccharide 5% aq. and 1% aq., which remained until D6. There was no reaction to glucan oligosaccharide 0.1% aq. Seven control patients were negative. A doubtful reaction (þ?) was shown to the skin lotion in which the glucan oligosaccharide content had been reduced to 10% of the normal level used in the product. There was no reaction to the skin lotion in which the glucan oligosaccharide content had been reduced to 1%of the normal level or to the lotion in which no glucan oligosaccharide was present. A 1-day closed patch testing with glucan oligosaccharide 5% aq. in 35 control subjects gave negative reactions, and one control gave a doubtful reaction. After the patient ceased application of the skin lotion, the dermatitis cleared.We concluded that the patient had developed allergic contact dermatitis caused by glucan oligosaccharide.

Quantification of allergic and irritant patch test reactions using ImageJ

It is often difficult to differentiate between allergic and irritant patch test reactions by visual inspection. The purpose of this study was to test an image analysis‐based method that differentiates between the two reactions by quantifying the degree of erythema at the patch test site.