Acne is generally understood to be the medical condition of “Acne vulgaris“. This disease of the skin affects the sebaceous glands and hair follicles in the true sense of the word. These initially develop into non-inflammatory comedones and, as the disease progresses, a series of inflammatory skin symptoms such as nodules, pustules and papules.

Acne (Acne vulgaris) is the most common skin disease. Almost everyone is affected by it, although the disease usually begins around the age of 12 and recedes of its own accord at the end of puberty. However, the disease can also last until the age of 30.

About one third of the cases must be treated with medication. The gender distribution is approximately equal, but acne is usually more severe in boys. The increasing use of the “pill” in women also plays a role here, as it often has a positive effect on acne vulgaris.

A genetic predisposition for this skin disease is being discussed, as severe manifestations have been described in family history. Acne was already known in ancient times. The origin of the name has not been clarified.

Causes of acne

Acne vulgaris is caused by the simultaneous occurrence of different parameters: Acne begins with changes in the sebaceous glands. Stimulated by the sex hormones androgens and progesterone, which are produced in increased quantities during puberty (androgens) and premenstrually in women (progesterone), the glands enlarge and produce more sebum. In addition, the inside of the hair follicle becomes horny, which is called follicular hyperkeratosis.

As a result, the follicle is enlarged from the inside by this keratinization and is additionally “clogged”, so that the sebum formed accumulates and a comedo (“blackhead”, sebum-filled cyst of the skin) develops. What exactly causes this hyperkeratosis is unknown. The next step is the multiplication of certain bacteria (Corynebacterium acnes and granulosum).

These exist physiologically in the hair follicles and decompose the sebum. The increased number produces more decomposition products, which then cause an inflammation of the comedones. – Increase of the sebum flow = Seborrhoea

  • Follicular hyperkeratosis = increased formation of cells at the base of the hair follicle and as a result of this, cornification disorder
  • Multiplication of germs (Corynebacterium acnes and granulosum) in the hair follicles and subsequent inflammation
  • Influence of androgens

The symptoms are limited to the skin; the face is especially affected, but also the chest and back.

Different stages of acne are experienced: Acne comedonica is the first stage of acne. This means the appearance of “comedones”, which develop mainly on the chin, nose and forehead. A distinction is made between black (= open) and white (= closed) comedones, which usually coexist.

The white comedones, however, inflame more frequently and are thus in the next stage, namely “Acne papulopustulosa”. This is characterized by inflammation, in the course of which pustules (pus-filled “pimples“) form. This form is then referred to as folliculitis.

After healing, scars remain, but these are generally not very noticeable. If healing does not take place but progresses, an “Acne nodulocystica” / “Acne vulgaris conglobata” develops. In this case the spontaneous bursting or squeezing of the pustules causes infiltrates and abscesses (melting of tissue with formation of pus), which can form a coherent system with several outlets (“fistulas”) under the skin surface.

The most severe form of acne, and thus the last stage, combines all the aforementioned skin changes. In addition, there are also very conspicuous scars, so-called “acnekeloid”. In the vernacular this is also called “pockmarked”. Furthermore, complications of acne superinfection with other bacteria (staphylococci, enterobacteria, klebsielles, proteus) can occur. As special forms or from the picture similar diseases occur:

  • Non-inflammatory stage = Acne comedonica
  • Inflammatory stages:
  • Acne papulopustulosa
  • Acne nodulocystica /vulgaris conglobata
  • Defect stage as colourful picture plus scars
  • Acne cosmetica (caused by cosmetic products, especially in women older than 20)
  • Late acne (persistent acne in adult women due to elevated androgen levels)
  • Acne excoriée des jeunes filles (psychogenic influence)
  • Acne tropica (severe acne vulgaris due to superinfection with staphylococci) Acne neonatorum (in newborns, probably due to androgens of the mother)
  • Drug-induced acne (e.g. by corticosteroids, isoniazid, iodine, bromine)
  • Acne fulminans (severe, acutely beginning acne with fever, joint and organ problems)