Elastosis Perforans Serpiginosa
Elastosis perforans serpiginosa is classified as a perforating skin disorder. This rare cutaneous eruption is believed to be caused by an abnormal expulsion of fragmented elastic fibers from the dermis. The elastic fibers penetrate the surface of the epidermis and manifest as an unusual serpiginous eruption. It has been seen as an isolated finding but also can be seen in association with many underlying conditions, including Down syndrome, Ehlers-Danlos syndrome, and Marfan syndrome.
Clinical Findings: Elastosis perforans serpiginosa is a rare cutaneous perforating skin disease. It is much more commonly seen in the young adult population, and it has a significant male predominance, with a ratio of 4 : 1 to 5 : 1. The condition has been most often reported on the neck. The eruption typically begins as small red papules with an excoriated or slightly ulcerated surface. Initially, pruritus is the main symptom. Over time, the papules coalesce into serpiginous, “wandering” eruptions. They can be annular or semicircular. The rash runs a waxing and waning course, but most cases resolve spontaneously with or without therapy. Resolution on average occurs within 6 months, but cases lasting up to 5 years have been reported in the literature. Most cases are solitary in nature. Patients with underlying Down syndrome may have only one lesion or widespread cutaneous involvement. It has been estimated that up to 1% of patients with Down syndrome will develop evidence of this rash over the course of their lifetime. Approximately 33% of cases of elastosis perforans serpiginosa are associated with an underlying disorder (see box to right). An autosomal dominant pattern of inheritance has been described in a small number of cases, independent of any of the listed underlying conditions. The medication penicillamine has long been known to cause abnormalities of elastic fibers, and use of this medication has been shown to induce an eruption resembling elastosis perforans serpiginosa.
As the lesions progress, the epidermis ulcerates in pinpoint regions and the underlying fragmentized and abnormal elastic tissue extrudes. The areas may become more pruritic over time, and occasionally they are slightly tender. Most are asymptomatic. The appearance is most concerning for the patient and family members.
Histology: Abnormally fragmented eosinophilic elastic tissue can be appreciated on routine hematoxylin and eosin staining. Special elastic tissue stains can be used to better isolate and appreciate the elastic tissue. Examination of biopsy specimens shows an isolated area of acanthotic epidermis in which a passageway has formed. The passage begins in the superficial dermis and leads to the surface of the epidermis. This is filled with the abnormal elastic tissue, a few histiocytes, and an occasional giant cell. Early biopsies can show a cap of keratin overlying the passageway.
Pathogenesis: The cutaneous eruption is caused by the transepidermal extrusion of abnormally fragmented elastic fibers. The reason for the abnormality in the elastic fibers has yet to be determined, except in those cases induced by penicillamine. Penicillamine has been shown to disrupt proper formation of elastic tissue. The abnormally formed fibers are then extruded from the dermis.
Treatment: Many therapies have been attempted, and their use is anecdotal at best. There have been no randomized, prospective, placebo-controlled trials for the treatment of this eruption. Many destructive modalities have been attempted with varying success. Cryotherapy has the most information to support its use, but ablative carbon dioxide lasers have also been used with good results. No therapy is required, because these eruptions almost always spontaneously remit.