Acne vulgaris, commonly known as acne or pimples, is a common skin disorder that plagues about 85% to 100% of people at some time during their lives. It affects people of every age, gender and race, although it is more evident in teenagers. Acne vulgaris is actually characterized by non-inflammatory follicular papules or comedones as well as by inflammatory papules, pustules, and nodules in its more acute forms.

Acne vulgaris occur as it affects the areas of the skin with the densest population of sebaceous follicles. The common areas affected are the face, neck, upper part of the chest, and the back, although it may also appear on different parts of the body like the head and the genital area.

Numerous studies have noted that there are generally four major factors that are responsible for the development of an acne lesion. The pathogenesis of acne vulgaris is deemed multifactorial due to this finding. These four factors that trigger the development of acne vulgaris include the follicular epidermal hyperproliferation and hyperkeratinization, excess sebum, propionibacterium acnes, and inflammation.

The follicular epidermal hyperproliferation and hyperkeratinization actually appears to be one of the main events in the formation and development of acne vulgaris. The findings have noted that the increasing levels of the adrenally derived androgen dehydropiandrosterone sulfate (DHEAS) are correlated with the emergence of the microcomedo, which is actually the primary acne vulgaris lesion. This development may then aggravate the follicular epidermal hyperproliferation, which may also be stimulated by an alteration in sebum and lipid levels in the acne vulgaris lesions.

Excess sebum is the second factor in the formation of acne vulgaris. It plays its role as the hormonal changes greatly trigger the formation of acne vulgaris. Then, there is the P. acnes, which is a microaerophilic organism found in many acne vulgaris lesions. It basically stimulates inflammation by emitting proinflammatory mediators that disperse through the follicle wall. Some findings also note that hypersensitivity to P. acnes can explain why many of the people develop inflammatory acne vulgaris.

Finally, recent studies have shown that inflammation may be a primary or secondary phenomenon in the development of acne vulgaris. Its secondary inflammatory response has been shown on its association to P. acnes. However, the proinflammatory cytokines IL-1a expression has been recognized in the microcomedone, which may play a large role in the formation of acne vulgaris.

Acne vulgaris, through recent findings, has been found out to cause physical pain and psychological suffering. It can even lead to scarring which may last for a lifetime, and certain illness like fever and arthritis may result from it.