What is acne?
Acne, medically known as Acne Vulgaris and is a chronic disease of the pilosebaceous apparatus.
What causes acne?
The disorder is caused by abnormal desquamation of follicular epithelium that results in obstruction of the pilosebaceous canal. This obstruction leads to the formation of comedones which become inflamed because of overgrowth of bacteria. Presence of dental infections can also provoke a follicular inflammatory response resulting in recalcitrant. The exact cause of acne is unknown but heredity and age are predisposing factors.
The etiopathogenesis of acne vulgaris, a common disorder of youth and adolescence, includes four primary processes: hyperkeratinization (plugging) of the pilosebacous follicles, increased testosterone levels, bacterial colonization with Propionibacterium acnes, and inflammation.An excess of androgen is believed to contribute to development of acne in some patients. Acne is caused by hormones, androgen, and follicular keratinization, which leads to blocked pores, and P. acnes bacteria, which cause pustule to form. In the skin, the expression of androgen action is dependent on the reduction of testosterone to dihydrotestosterone mediated by the enzyme 5 alpha-reductase. Additionally, an exaggeration of this peripheral metabolism has been associated with acne in women.
The sebaceous gland is a target of androgens, and hormonal influences play an important role in the multifactorial pathogenesis of acne. In both men and women, acne may be related to an excessive hypersensitivity of the sebaceous end organ to androgens. However, in women, the ovarian and adrenal production and the plasma transport of androgens may be implicated, particularly in late-onset of persistent acne or with associated hirsutism. Many reports have shown that females with acne frequently have abnormal levels of circulating androgens.
What are the symptoms of acne?
Acne is associated with an increase in sebum secretion. It is charactised by open comedones (blackheads), closed comedones (whiteheads) and pustular nodules. Acne vulgaris is a common inflammatory dermatosis capable of producing significant psychological and physical scarring. It is also associated with several immunologic responses including the production of antibodies against Propionibacterium acnes, the gram-positive bacteria found in acne lesions.
Acne vulgaris is a skin disease affecting mainly young people. To its pathogenetical factors belong: excessive serum production, cornification of hair follicles and presence of different bacteria (Propionibacterium acnes, Staphylococcus epidermidis, Pityrosporum ovale) on the skin and within hair follicles leading to skin inflammation. A major pathogenic factor of acne is the disturbed keratinization of the follicular infundibulum.
Apert's syndrome is a congenital disorder characterized by the premature fusion of the cranial sutures and early epiphyseal closure. Severe pustular acne is a common feature.
Explosive and very severe acne such as pyoderma faciale, acne conglobata and acne fulminans are rare, the features that distinguish acne fulminans from the other conditions being systemic upset with fever, joint pain, malaise and leucocytosis.
How common is acne?
Acne is usually considered a disorder of adolescence, and a number of studies have examined the prevalence of this condition in the adolescent population. There are, however, relatively few data on the prevalence of acne in the adult population. This study shows a prevalence of clinical facial acne in women of 12%, which is likely to persist into middle age.
Acne vulgaris is very common, 85% of teenagers being affected at any one time. The reported prevalence of acne varies from 35 to over 90% of adolescents at some stage. In some studies the prevalence of comedones approaches 100% in both sexes during adolescence. The preval
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