What Is Acne?
Acne vulgaris is the most common skin condition, affecting nearly 85% of people between ages 12 and 24. It occurs when hair follicles become clogged with oil (sebum) and dead skin cells, leading to whiteheads, blackheads, pimples, or deeper lumps (nodules and cysts). While most common in teenagers, acne can affect people of all ages, including adults.
How Acne Forms
Acne develops through four key processes: (1) excess sebum production stimulated by androgens, (2) abnormal shedding of dead skin cells inside the follicle, (3) colonization by Cutibacterium acnes bacteria, and (4) inflammation. These processes clog pores and create the various types of acne lesions.
Acne develops through four key processes: (1) excess sebum production stimulated by androgens, (2) abnormal shedding of dead skin cells inside the follicle, (3) colonization by Cutibacterium acnes bacteria, and (4) inflammation. These processes clog pores and create the various types of acne lesions.
Types of Acne Lesions
Non-inflammatory:
- Whiteheads (closed comedones): Clogged follicles beneath the skin surface
- Blackheads (open comedones): Clogged follicles open to the surface; the dark color is from oxidized melanin, not dirt
Inflammatory:
- Papules: Small, red, tender bumps
- Pustules: Papules with pus at the tip
- Nodules: Large, solid, painful lumps deep beneath the skin
- Cysts: Deep, painful, pus-filled lumps that can cause scarring