History:

Hidradenitis suppurativa is seen in areas with a lot of apocrine glands. Clinically there are abscesses with sinus tracks and scarring. Occasionally this is worse in obese individuals and there is an inherited variant. Other similar conditions include acne conglobata and perifolliculitis capitis abscedens et suffodiens which have a similar histology. Basically they are all part of a follicular occlusion triad and the follicles are obstructed by keratinous material. There is marked perifollicular infiltrate, abscesses with destruction of the para sebaceous unit and there are often foreign body granulomas.

See this Virtual Slide of HS in Path Presenter