Background: In the 2010s an epidemic of allergic contact dermatitis to methylisothiazolinone (MI) occurred in Europe. European authorities banned the use of methylisothiazolinone in leave-on cosmetics in 2017 and limited its use in rinseoff products in 2018. Objectives: To investigate the sensitization rate to MI in Belgium between January 2014 and December 2019, and to assess cosensitizations to octylisothiazolinone (OIT) and benzisothiazolinone (BIT) in MI-sensitized patients. Methods: A retrospective study of patch test results with MI, OIT, and BIT observed in patients attending five Belgian hospitals.Results: Overall, 560 of 10 029 patients (5.58%) had a positive patch test reaction to MI, and its sensitization rate decreased from 7.9% in 2014 to 3.1% in 2019. Rinse-off cosmetics, paints, and detergents were the most prevalent sensitization sources in recent years. Simultaneous reactions readily occurred to OIT, and, surprisingly, and increasingly, also to BIT.Conclusions: Contact allergy to MI in Belgium has reached a pre-epidemic level, reflecting the impact of recent regulatory measures. Leave-on cosmetics, in contrast to rinse-off products, have almost disappeared as sensitization sources in Europe.Paints and detergents also remain problematic. The remarkably high number of patients (co)sensitized to BIT should be a focus of future research.

A 10-month-old boy with congenital lamellar ichthyosis presented with a chronic Trichophyton rubrum infection. There was no history of atopy or immunosuppression, and examination revealed high total immunoglobulin E (IgE) with a positive specific IgE for T. rubrum. Multiple treatments with fluconazole were necessary to control the infection. T. rubrum is present worldwide and is responsible for the vast majority of chronic dermatophytosis. Lamellar ichthyosis is a risk factor for chronic dermatophytosis because of excessive keratin and the barrier defect. A delayed-type hypersensitivity reaction to T. rubrum is associated with cure, whereas immediate hypersensitivity and IgE are not protective and may lead to chronic infection. Atopy and the Th2 profile therefore seem to be associated with chronic dermatophytosis. The association between ichthyosis and atopy is well documented. T. rubrum also has an interesting ability to evade immunity, which helps explain the chronic infection. Finally, in ichthyosis, it is likely that fluconazole has difficulty penetrating the acanthotic stratum corneum, which explains treatment failure. We report this case to alert clinicians to the possible association between lamellar ichthyosis and chronic dermatophytosis and to report the difficulties of management.

No abstract

A 37-year-old woman with a history of mild atopic dermatitis involving her antecubital flexures and, sporadically, her face presented with 242 SCHEERS ET AL. face eczema that she had experienced for 1 year. Because of acne and solar brown spots, she had applied a retinoic acid-containing cream for 1 year, and she had slowly developed recalcitrant face eczema that was unsuccessfully treated with different moisturizing creams, corticosteroid creams, and sunscreens. As her face eczema further worsened, she was referred for patch testing.Patch tests were performed with the Belgian baseline and extended series, and with cosmetic, pharmaceutical, fragrance and corticosteroid series. Patch and photopatch tests were also performed with the sunscreen series and face cosmetics. Readings were positive on day (D) 2 (+) and D3 (++) for thiomersal and for the "BB crème teintée Anthelios 50+" (La Roche Posay) in patch and photopatch tests.The reaction to the cream was not photoaggravated and was, in fact, identical in both ultraviolet (UV)-exposed and non-exposed sites. The reaction to the sunscreen was confirmed by a positive repeated open application test result after 2 days of application. In a second session, patch and photopatch tests were performed with the sunscreen ingredients kindly provided by La Roche Posay. Readings showed a positive reaction to Scutellaria baicalensis root extract 0.2% aq./ethanol on D2(+) and D3 (++), with no photoaggravation. This extract was subsequently patch tested in 10 controls, and all readings were negative.We advised the patient to avoid this sun cream, and also products containing S. baicalensis. The patient's face dermatitis did not recur.

POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin disorders) is a rare multisystemic disease associated with plasma cell dyscrasia. A 68-year-old woman with chronic renal insufficiency and arterial hypertension included in her medical history was admitted to the hospital with confusion, somnolence and asthenia. She presented ascites, hepatosplenomegaly, leg oedema, distal dysesthesias, leuconychia and multiple nodular purple red angiomas on the trunk, upper limbs and fingers. Hypothyroidism was revealed in the laboratory investigations and monoclonal IgG peak in immunoelectrophoresis. Electromyography showed both demyelinisating and axonal degenerative neuropathy. The diagnosis of POEMS syndrome was based on the dermatopathological examination of a cutaneous angioma; histology revealed features of glomeruloid angioma, a specific marker of this syndrome.