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Acne at its most basic is a disorder of the pilosebaceous unit, or what is commonly called the hair follicle or pore. According to the American Academy of Dermatology, it is the most common skin disorder in the United States. Acne vulgaris, as common acne is known, is classified as a chronic inflammatory disease of the skin.
Acne is characterized by the presence of pimples or “zits”, blackheads, and whiteheads. It chiefly affects the face, neck, chest, back, and/or upper arms of sufferers. Rarely you will find acne in other areas of the body. Acne varies in development from very mild to extremely severe.
Acne is a skin condition that occurs due to the overproduction of oil by the oil glands of the skin. The oil that normally lubricates the skin gets trapped in blocked oil ducts and results in what we know as pimples, blackheads, and whiteheads on the surface of skin. Sometimes it also includes deeper skin lesions that are called cysts.
What is Acne?
Acne is the term for plugged pores (blackheads and whiteheads), pimples, and even deeper lumps (cysts or nodules) that occur on the face, neck, chest, back, shoulders and even the upper arms. Acne affects most teenagers to some extent. However, the disease is not restricted to any age group; adults in their 20s – even into their 40s – can get acne. While not a life threatening condition, acne can be upsetting and disfiguring. When severe, acne can lead to serious and permanent scarring. Even less severe cases can lead to scarring.
Types of Acne
When you read about acne or other skin diseases, you encounter words or phrases that may be confusing. For example, the words used to describe the lesions of acne—comedo, papule, pustule, nodule and cyst—are understandable only if you know each word’s definition. It also is helpful to have a photo that is characteristic for each type of lesion.
Here is a brief summary of definitions of words used to describe acne, with accompanying photos. Let’s begin, though, with the definition of lesion, an
all-purpose word:
Lesion—a physical change in body tissue caused by disease or injury. A lesion may be external (e.g., acne, skin cancer, psoriatic plaque, knife cut), or internal (e.g., lung cancer, atherosclerosis in a blood vessel, cirrhosis of the liver).
Thus, when you read about acne lesions you understand what is meant—a physical change in the skin caused by a disease process in the sebaceous follicle.
Acne lesions range in severity from comedones (blackheads and whiteheads) to nodules and cysts. Here is a brief definition of acne lesions:
Comedo (plural comedones)—A comedo is a sebaceous follicle plugged with sebum, dead cells from inside the sebaceous follicle, tiny hairs, and sometimes bacteria. When a comedo is open, it is commonly called a blackhead because the surface of the plug in the follicle has a blackish appearance. A closed comedo is commonly called a whitehead; its appearance is that of a skin-colored or slightly inflamed “bump” in the skin. The whitehead differs in color from the blackhead because the opening of the plugged sebaceous follicle to the skin’s surface is closed or very narrow, in contrast to the distended follicular opening of the blackhead. Neither blackheads nor whiteheads should be squeezed or picked open, unless extracted by a dermatologist under sterile conditions. Tissue injured by squeezing or picking can become infected by staphylococci, streptococci and other skin bacteria. The following photos are characteristic of acne with comedones:
(Photos used with permission of the American Academy of Dermatology
National Library of Dermatologic Teaching Slides)
Papule—A papule is defined as a small (5 millimeters or less), solid lesion slightly elevated above the surface of the skin. A group of very small papules and microcomedones may be almost invisible but have a “sandpaper” feel to the touch. A papule is caused by localized cellular reaction to the process of acne. This photo shows papules and comedones on the face of an acne patient:
