Acne is a disorder that involves the hair-oil (pilosebaceous) apparatus of the skin. Acne vulgaris or common acne (referred to herein as adolescent acne) begins in the teen or preteen years. In general, it becomes less active as adolescence ends, but it may continue into adulthood. Acne that initially occurs in adulthood is designated post adolescent acne or adult-onset acne.

Despite the clinical similarities and occasional overlapping of adolescent and post adolescent acne, the pathogenesis and treatment of each are often different.
Acne-like disorders, such as neonatal acne, drug induced acne, rosacea, and other so-called acne form conditions, are also considered separate entities because of differences in pathogenesis and treatment.

CLASSIFICATION OF ACNE:

Adolescence acne (Acne Vulgaris). Preteen acne and adolescent acne (which may persist into adulthood).
Post adolescent Acne
Female adult-onset acne.
Female adult-onset acne concurrent with adolescent acne that has persisted into adulthood.
Postmenopausal acne.
Endocrinopathic acne.
Male adult-onset acne (rare).

In addition, the following are acne disorders:
Folliculitis.
Hidradenitis suppurativa.
Pseudofolliculitis barbae.
Acne keloidalis.
Neonatal acne.
Rosacea.
Perioral dermatitis.
Drug-induced acne.
Physically induced and occupational acne.

INFLAMMATORY LESIONS
Papules: Superficial red bumps ("zits") that may have crusted. Scabbed surfaces caused by picking or squeezing.
Pustules: Superficial raised lesions containing purulent material, generally found in the company of papules.
Nodules: Large, deep papules or pustules.
"Cysts:" Acne "cysts" are not really cysts. True cysts are neoplasms that have an epithelial lining. Acne "cysts" do not have an epithelial lining; they are composed of poorly organized, variously shaped and blackhead or whitehead. Alternatively, the microcomedo may become an inflammatory lesion, such as a papule or pustule. The development of inflammatory lesions is theoretically as follows: Androgenic hormones stimulate sebaceous glands to increase in size and function and thus to produce more sebum (oil). The skin becomes oilier and the microcomedo becomes more hospitable to the anaerobe Propionibacterium acnes.

No inflammatory lesions:
The combination of open and closed comedones, as seen here, is most common in younger patients.
Sized conglomerations are inflammatory material.
Macules: The remains of formerly palpable inflammatory lesions that are in the process of healing from therapy or spontaneous resolution. They are flat, red or sometimes purple blemishes that slowly heal and may occasionally form a depressed (atrophic) scar.

COMEDONAL (NONINFLAMMATORY) LESIONS

A comedo is a collection of sebum and keratin that forms within follicular ostia (pores).
Open comedones (blackheads) have large ostia that are black not from dirt but from melanin.
Closed comedones (whiteheads) have small ostia. A combination of both inflammatory and comedonal acne is most commonly seen in younger patients.

Read our products review: acne-stop.com