The term acne does not mean JUST pimples.
Acne is a term for plugged pores (blackheads, whiteheads), pimples and even deeper lumps (cysts or nodules), that occur on the face, neck, chest, back, shoulders and even the upper arms.
There are several variations of acne that skin experts coined.
Whiteheads are caused by completely blocked pores. The white appearance is caused by the bacteria inside turning the sebum into free fatty acid. 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.
Types of acne
Acne Vulgaris (common acne) includes several types of lesions, usually called blackhead, whitehead, papules, pustules, nodules and cyst.
Mild to moderate acne vulgaris is characterized by:
Blackheads are caused by partially blocked pores. The black appearance is caused by melanin pigment from dead skin cells. Blackheads tend to be stable structures, and often take a long time to clear.
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.
Papules are small, red, tender bumps or spots. 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.
Pustules are larger, red and inflamed-pus filled spots.
On the other hand, severe acne vulgaris is characterized by:
Nodules are large and hard bumps under the skin’s surface. Unlike a papule, a nodule is characterized by inflammation, extends into deeper layers of the skin and may cause tissue destruction that results in scarring. A nodule may be very painful.
Cysts are similar to nodules but can be severely inflamed and infected.
Acne Rosacea is a variant that typically causes a red nose and is more common in older people than in young people, mostly affecting those who are aged 30 and above. It commonly appears as red rash, which are normally confined, to the cheeks, nose, forehead and chin. The redness is often accompanied by bumps and pimples. Blood vessels may also become more visible on the skin. People with this kind of acne rarely have pimples. These flashes can be triggered by certain foods like spicy foods and alcohol.