An Adolescent with a Peculiar Scar on the Scalp

Abstract

Osteoma cutis is a benign and rare dermatological condition defined by bone formation in the subcutaneous tissue or the deep dermis that may occur at any age. It can be either primary or secondary. Clinical lesions may present as papules, plaques, nodules, or as miliary, 1–4 mm lesions that are usually asymptomatic.

In osteoma cutis a characteristic histopathologic modification is bone developed by membranous ossification in subcutaneous tissue or the deep dermis.

The authors present the case of a 16-year-old male with erythematous firm papules grouped on a partially alopecic plaque on the parietal scalp. The asymptomatic lesions evolved in the last 2 years prior to the presentation. The diagnosis was based on the histopathological examination that showed bone metaplasia. The phospho-calcic metabolism was investigated, and the patient was referred to the pediatric nephrology ward for hypercalciuria.

Rare or common conditions can be considered in the differential diagnosis of osteoma cutis, as calcinosis cutis, dermoid cyst, keloid and hypertrophic scar, pilomatrixoma, or nevus sebaceous Jadassohn.

Treatment for cutaneous ossification is mainly surgical with the excision of neoformed bone, with the possibility of recurrence, especially in the genetic forms.