A 73-Year-Old With a Linear Rash

Abstract

A 73-year-old man with a history of bilateral hip replacements developed a unilateral, asymptomatic skin eruption on his left buttock 3 months after a left hip revision. Over the ensuing 3 years, he noticed mild irritation with heat exposure. Hydrocortisone 1% cream provided no benefit. Skin examination revealed linear pink to brown papules with overlying scale, which did not involve his previous surgical scar site (Figure 1). The clinical differential diagnosis included linear lichen planus, lichen striatus, persistent postherpetic granulomatous skin eruption, or other linear skin entities. Punch biopsy showed acantholytic dyskeratosis. A diagnosis of segmental Darier disease (DD) was made (Figure 2).Figure 2Histopathology of the linear rash showed (A) focal acantholysis (black arrows) within the epidermis. B, Acantholysis is occurring just above the basal layer of the epidermis (yellow arrow). There is dyskeratosis with characteristic “corp ronds” (long black arrow) and “grains” (short black arrow). (Hematoxylin and eosin stain [A] 10x original magnification, [B] 20x original magnification.)View Large Image Figure ViewerDownload Hi-res image Download (PPT) DD, a disease of keratinocyte adhesion, presents with grouped keratotic papules that are aggravated by heat and sweating and tends to develop during the third to fourth decades.1Burge S. Wilkinson J. Darier-White disease: a review of the clinical features in 163 patients.J Am Acad Dermatol. 1992; 27: 40-50Abstract Full Text PDF PubMed Google Scholar DD affects the body symmetrically. Segmental DD, however, presents with lesions arranged along the lines of Blaschko (segmental distribution). Diagnosis may be delayed because of the rarity of this entity. DD is an autosomal dominant genodermatosis caused by germline mutations in the ATP2A2 gene, which causes haploinsufficiency of epidermal calcium ATPase.2Sartori-Valinotti J. Peters M. Wieland C. Segmental type 1 Darier disease: a case series highlighting late-onset disease.Br J Dermatol. 2015; 173: 587-589Crossref PubMed Scopus (6) Google Scholar Segmental DD is thought to be caused by genetic mosaicism of the same gene. This mutation leads to keratinocyte discohesion and acantholytic dyskeratosis (rounding up and separation of individual keratinocytes, with accompanying abnormal keratinization), features that can be observed microscopically with skin biopsy (Figure 2).2Sartori-Valinotti J. Peters M. Wieland C. Segmental type 1 Darier disease: a case series highlighting late-onset disease.Br J Dermatol. 2015; 173: 587-589Crossref PubMed Scopus (6) Google Scholar, 3Harboe T. Willems P. Jespergaard C. Mølgaard M. Sørensen F. Bisgaard M. Mosaicism in segmental Darier disease: an in-depth molecular analysis quantifying proportions of mutated alleles in various tissues.Dermatology. 2011; 222: 292-296Crossref PubMed Scopus (15) Google Scholar, 4Pels I. Goodman M. Criteria for the histologic diagnosis of keratosis follicularis (Darier): report of a case with vesiculation.Arch Derm Syphilol. 1939; 39: 438-455Crossref Scopus (7) Google Scholar DD has a chronic course, and the goal of treatment is to limit exacerbations and prevent secondary infections.5Vogt K. Lohse C. El-Azhary R. et al.Kaposi varicelliform eruption in patients with Darier disease: a 20-year retrospective study.J Am Acad Dermatol. 2015; 72: 481-484Abstract Full Text Full Text PDF PubMed Google Scholar