Spurred by inflammation of skin glands and of tiny, narrow canals in the skin known as hair follicles, acne is marked by pimples and other lesions. It commonly appears on the face, neck, back, chest, and shoulders. Acne is not usually a serious health condition. “But it can cause significant emotional distress, as well as
permanent scarring of skin tissue,” says Liedtka, who has 15 years of clinical experience treating acne. She now works in CDER’s Division of Dermatology and Dental Products.
A Disease of the PSUs Clinically, acne is described as a disease of features known as pilosebaceous units (PSUs). Found just under the skin, PSUs are numerous on the face, upper back, and chest, and contain sebaceous glands that are connected to hair follicles. The sebaceous glands produce sebum, an oily substance that empties onto the skin via the hair follicle.