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.
After all, the stuff that comes out of your pores doesnât seem clean at all. But underneath your skin are glands called sebaceous glands, and they have a very important purpose. The oil excreted by the sebaceous glands, called sebum, acts like a glue to cling to dead skin cells. The skin cells are then excreted from the body through the pores to help you maintain healthy skin. Sometimes, as the glands expel these dead skin cells, build-up can occur and your pores will clog. The gland will continue to produce oil with no way to release the excess. The result is an infection called a pimple or blackhead.