Primary anetoderma with undifferentiated connective tissue disease.

Anetoderma is a rare benign elastolytic disorder that is characterized by focal loss of elastin fibers on histopathology and is often recalcitrant to treatment. We present a case of a patient with a 20-year history of pruritic and painful hyperpigmented atrophic papules clustered on the neck, axillae, inframammary folds, and right medial thigh. Although the histopathologyof her axillary lesions was consistent with anetoderma, her clinical presentation is unusual given the extent of involvement, reported pain and pruritus, and sharp demarcation of the distribution. The diagnosticuncertainty of this case led to added difficulty in management of a disease that is already notoriously difficult to treat and may significantly impact patient's quality of life.