Hidradenitis suppurativa can affect one spot or multiple areas of the body. Signs and symptoms of hidradenitis suppurativa include: 1  Blackheads. Small pitted areas of skin containing blackheads â often appearing in pairs or a double-barreled pattern â are a common feature.  Red, tender bumps. These bumps often enlarge, break open and drain pus.
Sebum is an oily substance that's secreted by sebaceous glands to keep skin moisturized. Too much leads to oily skin and too little leads to dry skin. Sebum is an oily substance that's secreted by sebaceous glands to keep skin moisturized.
Think back to the last time you went a few days without washing your hair, and try to remember the greasy crap that built up. Or, go rub your hands in the hair of the nearest hobo. That sticky substance is sebum, which is made from the delightful recipe of wax and the remains of dead fat-producing cells.