Yoon-Soo Cindy Bae-Harboe, MD; Emmy M. Graber, MD
Boston University, Department of Dermatology, Boston, Massachusetts

Disclosure: The authors report no relevant conflicts of interest.

Abstract
Background: No term exists to date describing the phenomenon of pink-to-red discoloration after an inflammatory acne lesion. Objectives: To introduce new terminology into the dermatology literature to describe erythema often seen after inflammatory acne vulgaris and to present a treatment option for this type of erythema. Methods: New terminology describing erythema after inflammatory acne is addressed, and a treatment option for postinflammatory erythema is presented. Results: Postinflammatory erythema is a new, accurate descriptor of erythema that occurs after inflammatory acne. Additionally, pulsed dye laser treatment improved postinflammatory erythema in the authors’ patients. Limitations: This paper only presents anecdotal cases. Conclusion: The addition of postinflammatory erythema to the dermatology literature may facilitate accurate communication among providers and direct laser treatment for postinflammatory erythema. (J Clin Aesthet Dermatol. 2013;6(9):46–47.)

The authors propose that a new term, post-inflammatory erythema (PIE), be added to the dermatology lexicon. In practice, many patients suffering from acne not only have the after effects of scarring (boxcar, rolling, and ice pick), but also have postinflammatory dyspigmentation. In darker skin phototypes, this postinflammatory dyspigmentation often presents as hyperpigmentation. However, in patients with lighter skin types (I–III), the postinflammatory dyspigmentation is often not hyperpigmentation, but instead discrete erythematous macules. Acne may not be the only cause of postinflammatory erythema, as any resolving cutaneous inflammatory process may have residual erythema. In contrast, erythematotelangiectatic rosacea is a separate diagnosis as the redness of rosacea is not part of a resolving process.

Postinflammatory erythema differs from postoperative erythema1 that is described in the literature, as the latter attributes the erythema to a procedure and is found within a surgical scar. PIE refers to localized skin erythema following any type of skin inflammation, including the erythema that may result in a scar. Accordingly, PIE may reside on normal skin or within a scar, whereas postoperative erythema is limited to a surgical scar.

Accurate use of terminology is important to improve communication not only among dermatologists, but also when speaking to patients. This is particularly helpful as many treatment options are available for the sequelae of acne.

Acne may resolve with postinflammatory hyper-pigmentation (PIH), PIE, or true scars, which often cause a textural skin change. PIE is distinct from PIH because PIE describes residual erythema, while PIH describes subsequent pigment change. Both PIH and PIE tend to resolve over time, thus differing from a true scar that persists. Oftentimes, patients will have any combination of PIH, PIE, and true scars. Recognizing these distinctions is essential to adequately meet the patients’ concerns over residual acne imperfections. The physician should ask the patient to identify the lesions of concern to direct treatment toward either PIH, PIE, or true scars, as each has a unique therapeutic approach.

The authors present two patients who, after successful treatment of their facial acne, had residual post-inflammatory erythema. For treatment of the PIE, the authors utilized the pulsed dye laser.

Case 1
A 30-year-old woman with postinflammatory erythema secondary to acne was successfully treated with pulsed dye laser (Figures 1 and 2). Treatment was administered to the face using the pulsed dye laser (Vbeam Perfecta 595nm; Candela SPTL IB, Candela Laser Corp, Wayland, Massachusetts) at a fluence of 6.50J/cm2, 3ms pulse duration, 10mm spot size, two passes, for a total of one treatment. The patient was thrilled with the outcome at her follow-up appointment one month later.

Case 2
A 16-year-old boy with acne that resolved during isotretinoin treatment underwent pulsed dye laser with substantial improvement in the appearance of his postinflammatory erythema with no complications (Figures 3 and 4). Treatment was administered to the face using the pulsed dye laser. The setting employed for the first treatment was a single pass at a fluence of 5.75J/cm2, 1.5ms pulse duration, and 10mm spot size. The same setting was utilized at subsequent visits one and three months later. At each visit, the patient and his father were both very pleased with the improvement seen after each treatment.

Both patients tolerated the procedure well without anesthesia and there were no complications.
Using the principles of selective photothermolysis,2 the pulsed dye laser (595nm) targets hemoglobin to safely and effectively treat various small-diameter vascular processes, such as capillary vascular malformations, hemangiomas, telangiectases, erythema, and angiomas. Large studies have demonstrated minimal side effects including atrophic scarring (0.8%), hyperpigmentation (1%), hypopigmentation (2.6%), and dermatitis (2%), among 500 treated patients.3 One of the authors’ patients also received his laser treatment while taking isotretinoin without any complications.

Other lasers and devices targeting vascular lesions are available on the market. The authors’ experience has shown that pulsed dye laser treatment is efficacious in treating patients with postinflammatory erythema. They propose the addition of postinflammatory erythema to the dermatology lexicon to facilitate accurate, effective communication and to direct appropriate treatment. Further studies are needed to establish safety, define optimal laser settings, and quantify the effectiveness of pulsed dye laser for postinflammatory erythema.

References
1.     Lee DH, Choi YS, Min SU, et al. Comparison of a 585nm pulsed dye laser and a 1064-nm Nd:YAG laser for the treatment of acne scars: a randomized split-face clinical study. J Am Acad Dermatol. 2009;60(5):801–807.
2.    Anderson RR, Farinelli W, Laubach H, et al. Selective photothermolysis of lipid-rich tissues: a free electron laser study. Lasers Surg Med. 2006;38(10):913–919.
3.    Levine VJ, Geronemus RG. Adverse effects associated with the 577 and 585 nanometer pulsed dye laser in the treatment of cutaneous vascular lesions: a study of 500 patients. J Am Acad Dermatol. 1995;32:613–617.