Many skin conditions can mimic acne vulgaris, and these are collectively known as acneiform eruptions. Such conditions include angiofibromas, epidermal cysts, flat warts, folliculitis, keratosis pilaris, milia, perioral dermatitis, and rosacea, among others. Age is one factor which may help distinguish between these disorders. Skin disorders such as perioral dermatitis and keratosis pilaris can appear similar to acne but tend to occur more frequently in childhood, whereas rosacea tends to occur more frequently in older adults. Facial redness triggered by heat or the consumption of alcohol or spicy food is suggestive of rosacea. The presence of comedones helps health professionals differentiate acne from skin disorders that are similar in appearance. Chloracne, due to exposure to certain chemicals, may look very similar to acne vulgaris.
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.