Exogenous acne

It has been foxmd that a combined application of cosmetic and facial rubbing can cause exogenous inflammatory acne. Exogenous acne refers to acneiform lesions due to external factors such as cosmetic agents, exposure to various oils, skin mbbing or friction or chlorance, now better called metabolizing acquired dioxin-induced skin hamartoma. 

This study reports a new form of severe inflammatory exogenous acne due to the association of two factors facial friction with cosmetic agents. Females aged 15,17, and 19 years presented at the clinic with severe inflammatory acne. In all cases, the face has been strongly rubbed in a compulsory marmer in the previous weeks with cosmetic agents [14 ]. The disease has not responded to various conventional acne treatments and was well controlled by a combination of oral corticosteroids and low-dose isotretinoin (1ST). Because cosmetic face friction as a cosmetic care becomes more and more fashionable, dermatologists should be aware of this severe clinical condition, which can occur in patients without a personal history of acne. 

Susceptibility to acne is also due to genetic factors. It does not follow Mendelian rules however, if both parents had severe acne when adolescents, their children are likely to present with clinical acne in puberty. Genetic factors play an important role in determining the size and the activity of sebaceous glands, while exogenous factors such as colonization of P acnes modulate the clinical expression of acne. Racial differences also exist. Caucasians are more prone to severe acne than black people. 

PIH can be observed after endogenous or exogenous inflammatory conditions. Essentially any disease with cutaneous inflammation can potentially result in PIH in individuals capable of producing melanin. Several skin disorders such as acne, atopic dermatitis, allergic contact dermatitis, incontinenti pigmenti, lichen planus, lupus erythematosus, and morphea have PIH as a predominant feature. Exogenous stimuli,both... 

Vitamin Bn-deficient cells contained about 30-45% less DNA than cells with physiological levels of the vitamin (Vorobjeva and Iordan, 1976 Iordan, 1992). The DNA content in these cells increased by up to 80% when AdoCbl was added to cultures growing in cobalt-ffee medium (Iordan et al., 1983) (Table 5.1). Strains with a potential capacity for high corrinoid synthesis demonstrated a more significant stimulation by exogenous AdoCbl than strains with low synthetic capacity (Fig. 5.7). However, P. acnes represented an exception to this rule it responded weakly to the addition of AdoCbl, despite having a high potential for vitamin Bn synthesis. 

Seneschal ], Kubica E, Boursault L, Stokkermans ], Labreze C, Milpied B, et al. Exogenous inflammatory acne due to combined application of cosmetic and facial rubbing. Dermat 2012 244(3) 221-3. 

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