Several scales exist to grade the severity of acne vulgaris, but no single technique has been universally accepted as the diagnostic standard.[68][69] Cook's acne grading scale uses photographs to grade severity from 0 to 8 (0 being the least severe and 8 being the most severe). This scale was the first to use a standardized photographic protocol to assess acne severity; since its creation in 1979, the scale has undergone several revisions.[69] The Leeds acne grading technique counts acne lesions on the face, back, and chest and categorizes them as inflammatory or non-inflammatory. Leeds scores range from 0 (least severe) to 10 (most severe) though modified scales have a maximum score of 12.[69][70] The Pillsbury acne grading scale simply classifies the severity of the acne from grade 1 (least severe) to grade 4 (most severe).[68][71]
Kathyrn Bowling’s son Gus was only two weeks old when she first noticed red bumps spreading on his face: newborn acne. At the time, the Atlanta mom wasn’t concerned about something so common (and harmless) as baby acne. I was worried about so many other things, like how much he was eating and whether I would get enough sleep,” she says. “In the grand scheme of things, a few bumps on his face didn’t seem too bad.”

Atrophic acne scars have lost collagen from the healing response and are the most common type of acne scar (account for approximately 75% of all acne scars).[32][33] They may be further classified as ice-pick scars, boxcar scars, and rolling scars.[31] Ice-pick scars are narrow (less than 2 mm across), deep scars that extend into the dermis.[32] Boxcar scars are round or ovoid indented scars with sharp borders and vary in size from 1.5–4 mm across.[32] Rolling scars are wider than icepick and boxcar scars (4–5 mm across) and have a wave-like pattern of depth in the skin.[32]
Acne appears to be strongly inherited with 81% of the variation in the population explained by genetics.[15] Studies performed in affected twins and first-degree relatives further demonstrate the strongly inherited nature of acne.[2][15] Acne susceptibility is likely due to the influence of multiple genes, as the disease does not follow a classic (Mendelian) inheritance pattern. Several gene candidates have been proposed including certain variations in tumor necrosis factor-alpha (TNF-alpha), IL-1 alpha, and CYP1A1 genes, among others.[19] The 308 G/A single nucleotide polymorphism variation in the gene for TNF is associated with an increased risk for acne.[40] Acne can be a feature of rare genetic disorders such as Apert's syndrome.[15] Severe acne may be associated with XYY syndrome.[41]

Therefore, it is very important that you wear sunscreen everyday, with an SPF of 30.Of note, after SPF 30, there are decreasing marginal returns in UVB protection. The % of UVB protection as a function of SPF Value is a log graph and plateaus after SPF 30. Therefore, there is not much difference in protection between SPF 40 and 50. Sunscreens with an SPF 100 are banned in some countries.

There are two big guns used to take down acne, and they're both great at doing entirely different things. Salicylic acid is a beta hydroxy acid that comes from willow bark and works primarily as an exfoliator, breaking down fatty acids like sebum so your pores don’t clog. (Glycolic acid works similarly but is less effective.) These acids are effective on comedones — whiteheads, blackheads, and other non-red bumps.

Acne vulgaris is a chronic skin disease of the pilosebaceous unit and develops due to blockages in the skin's hair follicles. These blockages are thought to occur as a result of the following four abnormal processes: a higher than normal amount of oily sebum production (influenced by androgens), excessive deposition of the protein keratin leading to comedo formation, colonization of the follicle by Cutibacterium acnes (C. acnes) bacteria, and the local release of pro-inflammatory chemicals in the skin.[50]
Scars (permanent): People who get acne cysts and nodules often see scars when the acne clears. You can prevent these scars. Be sure to see a dermatologist for treatment if you get acne early — between 8 and 12 years old. If someone in your family had acne cysts and nodules, you also should see a dermatologist if you get acne. Treating acne before cysts and nodules appear can prevent scars.