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.
Describe the location and function of sebaeous glands. 1  Sebaceous glands are located throughout the skin except in the palms of the hands and soles of the feet. 2  Sebum is an oily substance composed of fat (lipids) and the debris of dead fat-producing cells.  Sebaceous glands are classified as holocrine glands.