Acanthosis nigricans is a cutaneous lesion that has, in recent years, been of increasing interest to endocrinologists and diabetes specialists. What is the cause of the increased interest in this relatively uncommon skin lesion? The reason is the recognition that acanthosis nigricans is associated with a number of uncommon, but extremely interesting disorders characterized by cellular resistance to the action of insulin.1,2 In fact, acanthosis nigricans provides a major clinical clue to the existence of severe insulin resistance in many patients,3 and the lesion provides hints about the pathophysiologic basis of these syndromes.
What exactly is acanthosis nigricans? Clinically, it manifests as brown, velvety, hyperkeratotic plaques most often found in the axillae, the back of the neck, and other flexural areas.4 The lesions range in severity from minimal discoloration to extreme cases in which the entire surface of the skin may be involved. The pathologic changes are
Flier JS. Metabolic Importance of Acanthosis Nigricans. Arch Dermatol. 1985;121(2):193-194. doi:10.1001/archderm.1985.01660020051015