LAUSR

Dear Editor Darier's disease is a rare genodermatosis; heat and sweat, conditions usually worsening during summer months, are factors that have been reported to aggravate the disease (Cooper & Burge, 2003). Glycopyrrolate is an anticholinergic agent acting on nerves innervating eccrine sweat glands and decreasing sweat production (Pariser et al., 2019). It has been used successfully in treating patients with hyperhidrosis. Due to its antiperspirant effect, we aimed to evaluate the efficacy of topically applying glycopyrronium bromide 2% cream in Darier's disease patients. Our study included four Darier's disease patients (three females and one male) aged between 17 and 58 years with an otherwise unremarkable medical history. The submammary and lumbosacral sites were treated in every female (involved neck application in one subject). Chest and back were affected in the male, an athlete. Patients' clinical characteristics are depicted in Table 1. Every patient reported aggravated symptoms during hot weather and treatment was implemented during summertime. Thorough instructions were provided to patients about topically applying glycopyrronium every night. Other required treatments, for example, oral retinoid, were discontinued at least 3 months prior. Patients were evaluated at baseline and 3 months after glycopyrronium treatment commenced. Two different scales were used: Dermatology Life Quality Index (DLQI) and Physician Global Assessment (PGA). The latter was assessed as 0–25% for poor response, 25–50% for mild, 50–75% for moderate, and 75–100% for excellent response. We have previously used this assessment scale in published research (Kontochristopoulos et al., 2016). The DLQI baseline mean was 22. Three patients scored 27/30 and one 12/30. Mean DLQI was 11 after 3 months of treatment. Two patients scored 18/30, one patient 9/30 (Figure 1) and the latter 6/30 (initially 12/30; Figure 2). Physicians considered that there was moderate to excellent improvement in every patient (moderate improvement in three patients and excellent in one). Results are summarized in Table 1. No skin irritation or other adverse reactions were encountered. No secondary infection was observed in treated areas during treatment. No disease aggravation was observed during the 3 months follow-up period. Darier's disease treatment is challenging since it is a genetic disorder that cannot be treated. Advisable to avoid exacerbating factors; Topical medication can be useful in mild cases; Severe or refractory