Dermatitis®

The usefulness of using patient's own products in patch tests for the diagnosis of allergic contact eczema is well known. However, most of the literature is based on case series published decades ago, and they are focused on cosmetics and fragrances.

The aim of the study was to evaluate the usefulness of using patient's own products in patch tests for the diagnosis of contact eczema in a contact dermatitis unit, describing the most frequently positive own products, as well as the most frequently responsible allergens.

In a 17-year period, 3514 patients were patch tested in our department. In 2429 patients, patch testing with the patients' own products was performed.

We found that 363 patients (10.33%) reacted to their own products. In 131 cases (3.81%), reacting to their own product was the only clue for detecting the responsible allergen for allergic contact eczema. Most reactions were found for topical medications, moisturizers, and adhesives. Fragrance mix I, methylchloroisothiazolinone/methylisothiazolinone, ketoprofen, and colophony were found to be the allergens most often responsible.

It is essential to include patient's own products in the study of allergic contact eczema to make a correct diagnosis. In our series, 3.81% of the patients would not have been correctly diagnosed if their own products had not been included in patch tests.

When fragrance- and botanical-related (F/BR) allergy is identified, concomitant reaction (CR) frequencies can help direct avoidance recommendations.

This study aimed to determine the CR rates for F/BR allergens.

A retrospective cross-sectional analysis of the North American Contact Dermatitis Group data 2007–2016 was conducted. Frequencies of demographics, positive reactions, strength of reactions, trends, and CR rates were calculated.

A total of 5504 (22.7%) of 24,246 patients had F/BR allergic reactions. The F/BR-sensitive patients were more likely to be female, older than age 40 years, and White and have face, leg, or anal/genital dermatitis. Top allergens included fragrance mix I (FMI, 10.6%), Myroxylon pereirae (balsam of Peru [BOP], 8%), and fragrance mix II (FMII, 4.9%). There were increasing trends for FMI, FMII, cinnamic aldehyde, and Compositae mix and decreasing trends for BOP and propolis. When patients were positive to any F/BR allergen, they were likely to be positive to FMI, FMII, and BOP. Concomitant reactions were bidirectional between multiple fragrance allergens and propolis, colophony, and Compositae mix.

Concomitant reactions were identified between fragrances, between fragrances and BR allergens, and between BR allergens and fragrances. If CRs of greater than 10% suggest cross-reactivity, then all patients with fragrance sensitivity should avoid BR allergens and vice versa.

Little is known about the common photoallergens in New Zealand, where ultraviolet exposure is particularly high. Availability of photopatch testing is limited because of it being performed in very few tertiary referral and contact dermatitis clinics.

To review the photopatch testing experience in New Zealand.

A retrospective review of all patients who underwent photopatch testing at a tertiary referral center in Auckland from 2008 to 2019 was performed.

Seventy patients had photopatch testing over the 12-year period. Of the 58 patients tested using the photoallergen series, 6 (10%) patients had a positive photopatch test reaction, of which 4 were to promethazine and 2 were to benzophenone-3. The most common postpatch diagnosis was endogenous dermatitis (54%), followed by allergic contact dermatitis (21%), photoallergic contact dermatitis (9%), and chronic actinic dermatitis (4%).

Both patch and photopatch testing are important investigations in patients with suspected photoallergic contact dermatitis. Promethazine and benzophenone-3 were the most frequent and only photoallergens in our population. Promethazine sensitization was via oral exposure, supporting a mechanism of systematized photoallergy to promethazine.

Coronavirus disease 2019 has rapidly spread all over the world. Personal protective equipment (PPE) including masks and gloves is needed to avoid transmission. Adverse skin reactions associated with PPE have been described, but there is no information regarding objective measures to assess skin impairment related to PPE.

The aim of the study was to evaluate the impact of using facial mask and nitrile gloves on epidermal barrier function and skin homeostasis.

A cross-sectional study was designed. Thirty-four health care workers wearing nitrile gloves and a mask for 2 hours were included. Transepidermal water loss, stratum corneum hydration, erythema, and temperature were measured.

Transepidermal water loss (31.11 vs 14.24 g·m^–2·h^–1), temperature (33.29°C vs 32.57°C), and erythema were significantly greater at the area covered by gloves compared with the noncovered area. Transepidermal water loss (22.82 vs 13.69 g·m^–2·h^–1), temperature, and erythema (411.43 vs 335.52 arbitrary units) were significantly increased at the area covered by mask, whereas stratum corneum hydration was lower. Transepidermal water loss was greater at the area covered by a surgical mask than at a filtering respirator mask coded filtering facepiece 2 (27.09 vs 18.02 g·m^–2·h^–1, P = 0.034).

Skin homeostasis and epidermal barrier function may be impaired by gloves and mask use. High-quality PPE should be provided, and adequate skin prevention measures should be implemented to reduce epidermal barrier damage.

There are no reported cases of 2,4-dichloro-5-methylpyrimidine (DCP)–induced irritant contact dermatitis (ICD).

The aim of the study was to summarize the clinical features, treatment, and protective measures for DCP-induced ICD.

We retrospectively reviewed the clinical data from 64 patients with DCP-induced ICD and the protective measures in a DCP manufacturing factory.

Disease onset occurred 1 to 10 minutes after DCP single exposure in all 64 patients. The contact site developed edematous erythematous skin lesions with clear boundaries. Other symptoms included a burning sensation (n = 48), pruritus (n = 16), headache (n = 4), nausea/vomiting (n = 3), and syncope (n = 1). Ten patients developed pruritic rash over the whole body 1 to 4 days after contacting DCP. Histopathologic examination of the lesions was performed in 8 patients; all 8 showed manifestations of ICD. A patch test with 1% DCP ethanol solution was performed in 7 patients. One patient withdrew because of pruritus and massive erythema over the whole body. Four patients had a strong reaction, and 2 patients had a very strong reaction. All patients were cured. Positive-pressure inflatable protective clothing protected workers from the outside environment to prevent DCP-induced ICD.

2,4-Dichloro-5-methylpyrimidine exposure induces acute ICD and a delayed allergic reaction in some patients (15.6%). Positive-pressure inflatable protective clothing prevents DCP-induced ICD.