Lipedematous alopecia: a clinicopathologic, histologic and ultrastructural study.

Lipedematous alopecia is a rare condition of unknown etiology characterized by a thick, boggy scalp with varying degrees of hair loss that occurs in adult black females, with no clearly associated medical or physiologic conditions. The fundamental pathologic finding consists of an approximate doubling in scalp thickness resulting from expansion of the subcutaneous fat layer in the absence of adipose tissue hypertrophy or hyperplasia. Observations by light and electron microscopy detailed in this report suggest that this alteration principally manifests by localized edema with disruption and degeneration of adipose tissue. Some diminution in the number of follicles as well as focal bulb atrophy is noted. Aberrant mucin deposition such as that seen in myxedema or other cutaneous mucinoses is not a feature. The histologic findings bear some resemblance to those seen in lipedema of the legs, a relatively common but infrequently diagnosed condition. We present a case of lipedematous alopecia with emphasis on histologic and ultrastructural features. The etiology is unknown.