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.
Sebaceous+glands. The sebaceous glands are microscopic (tiny) glands in the skin which produce an oily/waxy substance, called sebum, to lubricate (oil) the skin and hair. In people, these glands are found in greatest amounts on the face and scalp, joined near the top inside hair follicles or sweat pores.