Hidradenitis suppurativa from the typical patient to the new clinical phenotypes.

Hidradenitis suppurativa (HS) is a clinically heterogeneous disease with a broad spectrum of clinical features. Attempts to classify HS into distinct clinical phenotypes could lead to a better understanding of the condition and the development of individualized treatment protocols. We summarize some of the existing phenotype classifications and present our experience with 250 patients and their many clinical presentations. We have emphasized the pathophysiologic and clinical overlap between HS and pyoderma gangrenosum. The more severe presentations can include erosive and ulcerative lesions, sometimes associated with vegetative changes leading to diagnostic quandaries. We propose a new phenotype of pyoderma gangrenosum-like HS in which painful ulcerative or vegetative lesions appear in sites affected by HS, their activity coincides with the flareups of classic inflammatory manifestations of HS, and they heal with cribriform or atrophic scars.