Acne keloidalis nuchae: another cutaneous symptom of metabolic syndrome, truncal obesity, and impending/overt diabetes mellitus?

Acne keloidalis nuchae (AKN) is an inflammatory disease related to the spectrum of keloidal scarring alopecias. No association with internal disease has been described so far. We describe a case series of four Indian patients who showed an association of AKN with acanthosis nigricans, a skin marker for the metabolic syndrome (in particular obesity). Well known risk factors for AKN such as curly hair or wearing of a helmet were not present in these patients. AKN shows some similarities to acne inversa. We propose that AKN may be considered a cutaneous marker for the metabolic syndrome but case-control studies will be necessary to validate this clinical observation. We hope that our findings will stimulate other dermatologists to search for such an association.