The troubling, frustrating part of acne: the persistent acne scars that are often a prolonged battle for most of our patients. We have many techniques to deal with postinflammatory hyperpigmentation (PIH). However, postinflammatory erythema (PIE), the erythematous scars often seen in acne and other inflammatory skin conditions, is not well understood. And despite its pervasive nature, very little data exist that identify its etiology and effective treatment options.
Inflammatory acne scars are not all the same. PIH, often seen with Fitzpatrick skin types III-VI, is related to brown spots, not red spots. Hyperpigmentation is caused by an excess production of melanin. There are treatments for PIH in our armamentarium – such as microdermabrasion, chemical peels, hydroquinone, and vitamin C – that inhibit melanogenesis and blend the skin discoloration.
In contrast, PIE is characterized by pink, red, and sometimes purple-appearing vascular neogenesis seen most often with skin types I-III after an inflammatory skin condition resolves, and is often seen in cystic acne.
The term postinflammatory erythema was initially introduced in the dermatology literature in 2013 by Bae-Harboe et al. to describe erythema often seen after the resolution of inflammatory acne or other inflammatory skin conditions.1 It is not to be confused with the erythema and telangiectasias seen in erythematotelangiectatic rosacea, which is a separate entity.
Anecdotal studies have shown that pulsed dye and Nd:YAG lasers, which target hemoglobin through the process of selective photothermolysis, are effective at decreasing the vascular prominence in PIE. In clinical practice, a combination of pulsed dye lasers, KTP laser, intense pulsed-light, and Nd:YAG lasers has been effective in reducing both the superficial and deep vascular prominence seen with PIE.2
In my practice, microneedling has also been effective in reducing PIE. Although this may seem counterintuitive because of the bleeding associated with the microneedling process, microneedling-induced skin tissue injury and neocollagenesis have been clinically shown to improve the abnormal vascular proliferation that occurs in PIE. Similar techniques can be used with fractional resurfacing lasers. However, no studies have specifically evaluated the erythematous component of acne scars treated with fractionated lasers.
Topical preparations containing brimonidine (Mirvaso), azelaic acid, and green tea, as well as oral nicotinamide, can have a temporary effect on reducing skin erythema.
However, very little data or clinical studies are available on treatments for PIE, and there are no well-studied preparations with long-term efficacy data.Studies are needed to provide better clinical guidelines for treatment methods and alternatives to treatments, including topical and systemic medications.
Dr. Talakoub and Dr. Wesley are co-contributors to this column. Dr. Talakoub is in private practice in McLean, Va. Dr. Wesley practices dermatology in Beverly Hills, Calif. This month’s column is by Dr. Talakoub. Write to them at firstname.lastname@example.org.