Acne is a medical condition describing blocked skin pores that result in lesions. The reasons why skin pores can become plugged with sebum, the natural oil produced by skins sebaceous glands aren’t entirely understood. Once plugged, dead cells and bacteria become trapped in the pore, resulting in the acne.
The most common lesions are called ‘comedones’. Comedones come in two basic varieties, ‘white heads’ and ‘black heads’. A white head is a plugged pore that has begun to bulge outward from the skin due to bacteria, dead skin cells, and other contaminants that have become trapped inside. The bulging dome shape often takes on a white appearance. Black heads are simply comedones that have become opened, revealing the dark follicle plug within. Acne comedones are often referred to as pimples.
Microcomedones are a less common form of acne lesion, sometimes referred to as papules. These are basically small comedones that form from localized cellular reactions to the processes that cause acne. That usually occur in clusters and are sometimes too small to see, but can be felt as a series of little bumps along the skin surface.
In more severe forms of acne, pustules, nodules and cysts can form. A pustule is like a normal comedone, but larger due to a higher amount of dead white cells, or pus, trapped inside the plugged sebaceous follicle.
Nodules are a more severe form of papules, extending deeper into the skin tissue and resulting in large raised legions that are usually inflamed, and painful to touch. Cysts are very large fluid filled sacs that can result from pustules or nodules. Though none of these forms of acne are dangerous or life threatening, they can leave scars and are sometimes very disfiguring.