Microcomedonic acne

Low levels of LA are found in the sebum of acne sufferers,200 and levels appear inversely related to sebum secretion rate.201 It has been hypothesized that this local EFA deficiency may lead to the follicular hyperkeratosis and occlusion of acne, and that an increased supply of linoleate might possibly ameliorate the condition.202 In support of this, digital image analysis revealed that topical application of LA over a one month period reduced the size of microcomedones.203 Decreased levels of LA may also contribute to acne inflammation by failing to inhibit phagocytosis and ROS generation by neutrophils.204... 

Letawe, C., Boone, M., and Pierard, G.E., Digital image analysis of the effect of topically applied linoleic acid on acne microcomedones, Clin. Exp. Dermatol., 23, 56, 1998. 

Tretinoin (Retin-A, others) has been used in the treatment of acne vulgaris for almost four decades. A primary use for tretinoin is to reduce the hyperkeratinization that leads to microcomedone formation, the initial lesion in acne. Follicular comeocytes become less cohesive as a result of shedding of desmosomes, decreasing tonofila-ments and increasing keratinocyte autolysis and intracellular deposition of glycogen. 

Blockage of the follicular opening due to hypeik-eratosis of epithelium in the follicular canal is the basis for microcomedones formation. Microcomedones are the first acne lesions and can be found in normal-looking skin. The distended follicular may rupture, causing further inflammatory reaction, leading to the formation of papules, pustules, cystis, and nodules. 

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