Idiopathic eruptive macular pigmentation: report on two cases

Idiopathic Eruptive Macular Pigmentation with Papillomatosis: A Common but Underdiagnosed Entity

Idiopathic Eruptive Macular Pigmentation (IEMP) is an uncommon and possibly underdiagnosed dermatosis. It manifests as asymptomatic pigmented macules over the face, trunk and proximal extremities among children and adolescents. Degos et al. first documented this condition in 1978, unveiling its distinct characteristics. The macules, initially dark brown-black, naturally diminish over several months to years, with no lasting pigmentation or scarring. In this report, we highlight the case of a 14-year-old girl displaying all the distinctive traits of IEMP.

Progression of Idiopathic Eruptive Macular Pigmentation in a Girl from Childhood to Adolescence: Case Report and Literature Review

A 14-year-old girl developed brownish round macules and patches over the face, trunk, and proximal limbs with extensive progression since she was 7 years old. Electron microscopy examination revealed an increase in the number and maturity of melanosomes in basal and suprabasal keratinocytes, although the number of melanocytes was within the normal range. A diagnosis of idiopathic eruptive macular pigmentation was made. We describe the unusual disease progression of this case of idiopathic eruptive macular pigmentation, which was thought to be self-limited.

Idiopathic eruptive macular pigmentation with papillomatosis

We present a case of an otherwise healthy 10-year-old girl who presented with asymptomatic brown macules over the trunk and proximal extremities, of three months’ duration. The cutaneous examination revealed multiple, dark brown, discrete, round to oval macules and a few mildly elevated lesions over the trunk and proximal limbs. The individual lesion was 1-3 cm in diameter and a few showed velvety appearance over the surface. Darier's sign was negative. The histopathological study from the velvety lesion showed acanthosis, papillomatosis and increased melanin in the basal layer. The upper dermis showed sparse perivascular infiltrate of lymphocytes without any dermal melanophages. It fulfilled the criteria for idiopathic eruptive macular pigmentation with additional histological finding of papillomatosis.