There are many types of acne classified according to appearance and severity. Acne starts to show up during puberty when the hormone testosterone, present in both males and females, causes the sebaceous glands in the skin to enlarge.
These glands naturally produce oil or sebum which serves to lubricate the skin and hair. As the skin continually sheds, some of the old skin cells are trapped inside the sebaceous glands together with the sebum, blocking the pore. If the opening of the pore is narrow or closed, a condition called whitehead or closed comedone occurs. If the opening of the pore remains open, it becomes a blackhead or open comedone.
It is commonly believed that blackheads are caused by dirt trapped in the pore openings. However, this is a misconception; they are black not because of dirt but because of oxidized keratin, a component of the skin cells trapped in the pores.
Bacteria called Propionibacterium acnes normally live in the pores. When a whitehead or blackhead occurs, an infection by p. acnes may develop and trigger inflammation, which is a defense mechanism of the body’s immune system. This results into the familiar pimple- a red, inflamed acne lesion also technically called a papule. If the pimple contains white blood cells, its medical term becomes a pustule.
Sometimes when p. acnes infect more adjacent cells and the inflammation spreads into the surrounding skin, the skin can develop more nodules and cysts. There can be bumps and pimples under the skin as well. This results into the so-called cystic acne with its “pizza-face” appearance. This type of acne is painful and is difficult to treat with topical preparations alone.
Dermatologists classify acne according to severity. Grade I acne is the mildest form, consisting of whiteheads and blackheads with no inflammation. They usually occur during early adolescence, typically affecting the nose area and the forehead. They easily respond to acne products containing salicylic acid.
Grade II is moderate acne characterized by the emergence of papules and pustules, or reddish pimples with signs of inflammation. Acne will typically appear in most parts of the face including the cheeks, and teens, especially males, may start seeing them on their backs or shoulders. Grade II acne still responds to over-the-counter medications such as those containing salicylic acid and benzoyl peroxide. These pimples could easily get worse or infected if habitually squeezed or picked at.
Grade III acne is considered severe with plenty of red and inflamed acne lesions, usually affecting not only the face but other parts as well including the neck, shoulder, back, chest, and upper arms. If left untreated, this type of acne easily leads to scarring. You should see a dermatologist when you start having Grade III acne.
Grade IV acne is the most severe type characterized by large painful cysts in addition to numerous papules, pustules, and nodules. The skin is visibly red and inflamed and will require powerful prescription medications from a dermatologist to be put under control.