Acne occurs in many forms.  Most popularly, acne refers to clogged pores turning into whiteheads and blackheads.  Acne is the ever dreaded pimple.  Acne can even be the deeper lumps that appear as nodules or cysts.  All of these can lead to scarring if not treated correctly.  Acne can occur anywhere.  Although most prominent on the face, it can also show up on the neck, shoulders, chest, back, and arms.

There are many different types of acne.  The most common, of course, is Acne Vulgaris.  The common offender to most of these acne types is:  BACTERIA!

     ACNE TYPES AND DEFINITIONS:

Many different words describe an acne problem.  Therefore, it’s important to note and understand what each word means.  We will start with the most general and get more specific.

• Lesion- An infected or diseased patch of skin (can accompany acne, skin cancer, a knife cut, etc.)  When we read about lesions, we recognize that it has to do with an infected sebaceous gland.  Some lesions are more severe than others.
• Comedo (plural Comedones)- when a sebaceous follicle is plugged with dirt, other cells, tiny hairs, or bacteria.  There are two types of comedones.  Blackheads are open comedones because the surface appears black.  Closed comedones appear as a slightly inflamed, skin colored bump and are called Whiteheads.
• Macule- a temporary red spot left from a healed lesion.  They are generally light red or pink and they can last from anywhere between a day to a few weeks.
• Pustule- Something likened to an inflamed, pus-filled lesion:  a small inflamed elevation of the skin that is filled with pus; a pimple.
• Papule- A small, solid, usually inflammatory elevation of the skin that does not contain pus.
• Nodule- Like a papule in that it is white and dome-shaped.  Characterized by inflammation.  Nodular acne is very severe and doesn’t respond well to many forms of therapy.
• Cyst-an embedded nodule of bacteria that is well below the skin and with rapid growth of skin over it which entraps the bacterial pus pocket. Unlike a large acne pimples which come to the surface within couple of days or 4 to 5 days, the cyst may take a couple of weeks or several weeks or even months to surface allowing the bacterial pocket to empty.

Acne vulgaris is the most common form of acne. It includes several types of lesion. Individual acne lesions usually last less than two weeks but the deeper papules and nodules may persist for months. It is a condition that mainly affects adolescents but may persist or even become more severe in adulthood. Most, but not all, acne patients have oily skin (seborrhoea). Acne vulgaris may occur on the face, chest, back and sometimes even more extensively. Several types of acne spots occur, often at the same time.

Medication induced acne: Acne can occasionally be caused by, or aggravated by, medications (drugs)such as Oral steroids may cause steroid acne; Contraceptive agents: medroxyprogesterone injection (Depo-Provera) and oral contraceptives which reduce circulating sex hormone binding globulin (SHBG), can aggravate acne in females, Testosterone, Anabolic steroids such as danazol, stanozolol can cause severe acne including acne conglobata and acne fulminans. Athletes and body-builders sometimes abuse anabolic steroids because they result in increased muscle bulk - severe acne is one of the undesirable results.

It is not known why some other medicines cause or aggravate acne; theories include effects on white blood cells and direct effects on the hair follicle. Medications known to aggravate acne include: Halogens (iodides, chlorides, bromides, halothane), Antiepileptics (carbamazepine, phenytoin, phenobarbital), Antituberculous drugs (ethionamide, isoniazid, rifampicin), Antidepressants (lithium, amoxapine), Cyclosporin, B vitamins (B12, cyanocobalamin).

Acne in Pregnancy: During pregnancy, acne can both clear and get worse. In early pregnancy, acne often gets a bit worse but as pregnancy progresses, acne can often improve, possibly because of increased levels of estrogen.

Severe Forms of Acne are rare, but they are a great hardship to the people who experience them, and can be disfiguring--and, like all forms of acne, can have psychological effects on the sufferer.

Acne conglobata: the most severe form of acne vulgaris and is more common in males. It is a form of nodulocystic acne in which there are interconnecting abscesses and sinuses, which result in unsightly hypertrophic (thick) and atrophic (thin) scars. There are groups of large "macrocomedones" and cysts that are filled with smelly pus. It can cause severe, irrevocable damage to the skin, and disfiguring scarring. It is found on the face, chest, back, buttocks, upper arms, and thighs. The age of onset for acne conglobata is usually between 18 and 30 years, and the condition can stay active for many years. 

Acne fulminans: an abrupt onset of acne conglobata which normally afflicts young men. Symptoms of severe nodulocystic, often ulcerating acne are apparent. As with acne conglobata, extreme, disfiguring scarring is common. Acne fulminans is unique in that it also includes a fever and aching of the joints.

Pyoderma faciale: This type affects only females, usually between the ages of 20 to 40 years old, and is characterized by painful large nodules, pustules and sores which may leave scarring. It begins abruptly, and may occur on the skin of a woman who has never had acne before. It is confined to the face, and usually does not last longer than one year, but can wreak havoc in a very short time.

Gram-negative folliculitis: a bacterial infection characterized by pustules and cysts, possibly occurring as a complication resulting from a long term antibiotic treatment of acne vulgaris. It is a rare condition, and we do not know if it is more common in males or females at this time.

Nodulocystic acne: a severe form of acne affecting the face, chest and back. Nodulocystic acne is charactered by multiple inflamed and uninflamed nodules and frequently, scars. It is more common in males.

Rosacea is sometimes called "acne rosacea" because it often occurs with acne. When rosacea is present, small, red, solid bumps (called papules) and pus-filled pimples (called pustules) may appear on the skin. These can easily be confused with acne pimples, but unlike acne, rosacea papules and pustules have no blackheads. Rosacea is sometimes called "adult acne," and it can be caused by harsh or aggressive acne treatments.