Darier disease (DD) is a rare dominantly inherited genodermatosis characterized by loss of intercellular adhesion (acantholysis) and abnormal keratinization. DD is often difficult to manage. Numerous treatments have reportedly been used for the treatment of DD, with limited success. Systemic retinoids are considered the drug of choice for treating DD. However, their use is limited by potential deleterious side effects. Considering the recently reported efficacy of doxycycline for Hailey-Hailey disease, an inherited acantholytic skin disorder pathogenetically similar to DD, we report the case of a patient with extensive DD who showed a dramatic response to oral doxycycline monotherapy.

Idiopathic facial aseptic granuloma (IFAG) is a rare, benign pediatric dermatological lesion that occurs in children between 8 months and 13 years of age. The pathogenesis of IFAG is still unclear but it is likely to be associated with granulomatous rosacea in childhood. Here we describe a case of IFAG in a 13-year-old boy who showed a dramatic response to oral doxycycline and topical metronidazole, which supports the hypothesis that IFAG may belong to the spectrum of rosacea.

Fig 1. Lentigines restricted to areas of previous psoriatic plaques 5 years after their occurrence.

Recent advances in targeted anticancer therapies have substantially improved the prognosis of several cancers. Such targeted therapies are not, however, free of side effects, and these side effects are clearly distinct from those induced by classical cytotoxic chemotherapies. This is likely so because targeted therapies are designed to interfere with specific oncogenic signaling pathways rather than to inhibit cell proliferation in general. In fact, interference with specific signaling pathways may lead to effects that mimic those associated with genetic disorders due to alterations in the corresponding signaling pathways. Here, we compare the clinical effects of treatment with BRAF inhibitors with those of genetic RASopathies and find a striking overlap between the inhibitor-induced, iatrogenic dermatoses with the genodermatoses seen in patients with corresponding congenital RASopathies. We hope that such comparisons lead to a better understanding of the side effects of targeted therapies.