LTB4 promotes skin inflammation by acting on the peroxisome proliferator-activated receptor alpha (PPARα) protein. PPARα increases the activity of activator protein 1 (AP-1) and NF-κB, thereby leading to the recruitment of inflammatory T cells. C. acnes ability to convert sebum triglycerides to pro-inflammatory free fatty acids via secretion of the enzyme lipase further explains its inflammatory properties. These free fatty acids spur increased production of cathelicidin, HBD1, and HBD2, thus leading to further inflammation.This inflammatory cascade typically leads to the formation of inflammatory acne lesions, including papules, infected pustules, or nodules. If the inflammatory reaction is severe, the follicle can break into the deeper layers of the dermis and subcutaneous tissue and cause the formation of deep nodules. The involvement of AP-1 in the aforementioned inflammatory cascade activates matrix metalloproteinases, which contribute to local tissue destruction and scar formation.Along with the bacteria C. acnes, the bacterial species Staphylococcus epidermidis (S. epidermidis) also takes a part in the physiopathology of acne vulgaris. The proliferation of S. epidermidis with C. acnes causes the formation of biofilms, which blocks the hair follicles and pores, creating an anaerobic environment under the skin. This enables for increased growth of both C. acnes and S. epidermidis under the skin. The proliferation of C. acnes causes the formation of biofilms and a biofilm matrix, making it even harder to treat the acne. Diagnosis
Acne vulgaris is diagnosed based on a medical professionals clinical judgment.
Acne, also known as acne vulgaris, is a long-term skin condition that occurs when dead skin cells and oil from the skin clog hair follicles. Typical features of the condition include blackheads or whiteheads, pimples, oily skin, and possible scarring. It primarily affects skin with a relatively high number of oil glands, including the face, upper part of the chest, and back. The resulting appearance can lead to anxiety, reduced self-esteem, and, in extreme cases, depression or thoughts of suicide.Susceptibility to acne is primarily genetic in 80% of cases. The roles of diet and cigarette smoking in the condition are unclear, and neither cleanliness nor exposure to sunlight appear to play a part. In both sexes, hormones called androgens appear to be part of the underlying mechanism, by causing increased production of sebum. Another common factor is the excessive growth of the bacterium Cutibacterium acnes, which is present on the skin.Treatments for acne are available, including lifestyle changes, medications, and medical procedures. Eating fewer simple carbohydrates such as sugar may minimize the condition. Treatments applied directly to the affected skin, such as azelaic acid, benzoyl peroxide, and salicylic acid, are commonly used. Antibiotics and retinoids are available in formulations that are applied to the skin and taken by mouth for the treatment of acne. However, resistance to antibiotics may develop as a result of antibiotic therapy. Several types of birth control pills help prevent acne in women. Medical professionals typically reserve isotretinoin pills for severe acne, due to greater potential side effects.