Refractory Postinflammatory Hyperpigmentation Treated With Fractional CO2 Laser

Yasemin Oram, MD; A. Deniz Akkaya, MD

The authors are from the Department of Dermatology, V.K. Foundation American Hospital of Istanbul, Istanbul, Turkey

Disclosure: The authors report no relevant conflicts of interest.

Abstract
Objective: Postinflammatory hyperpigmentation is a reactive hypermelanosis of the skin that occurs as a consequence of an inflammatory process, such as acne, eczema, drug reactions, burns, chemical peelings, and laser applications. Although topical agents remain to be the first-line treatment of postinflammatory hyperpigmentation, treatment of recalcitrant cases is challenging. The Q-switched ruby laser, the low-dose Q-switched neodymium-doped yttrium aluminum garnet laser, and the fractional 1550nm erbium-doped fiber laser have been reported to improve postinflammatory hyperpigmentation. Design/setting/participants: The authors present a case of refractory postinflammatory hyperpigmentation successfully treated with two sessions of fractional CO2 laser in a 24-year-old woman with Fitzpatrick skin type III. Results: After two treatment sessions with a one-month interval, the lesion totally cleared without any complications. Conclusion: Although many laser systems, including fractional CO2 lasers, can cause postinflammatory hyperpigmentation, they also can be very efficacious tools by using conservative laser settings and by providing appropriate post-treatment care in recalcitrant postinflammatory hyperpigmentation treatment.  (J Clin Aesthet Dermatol. 2014;7(3):42–44.)

Postinflammatory hyperpigmentation (PIH) is a reactive hypermelanosis of the skin. It appears as asymptomatic macules or patches that may be different in size and distribution depending on the causative pathology. Characteristically, it occurs as a consequence of an inflammatory process, such as acne, eczema, drug reactions, burns, chemical peelings, and laser applications. Increased amounts of arachidonic acid metabolites, cytokines, inflammatory mediators, and histamine in the inflammatory process may stimulate the melanocytes causing an increase in the melanin synthesis and transfer of pigment to the surrounding keratinocytes. In PIH, there is either excess melanin production or an abnormal distribution of melanin pigment deposited in the epidermis and/or dermis.[1]

Treatment of PIH consists of a variety of medications and procedures. These include topical bleaching agents, such as hydroquinone, azelaic acid, kojic acid, retinoids, vitamin C, chemical peels, laser therapy, and sunscreens.[1,2] The Q-switched ruby laser, the low-dose Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) laser, and the fractional 1550nm erbium-doped fiber laser have been reported to improve PIH.[1–4] Here, the authors present a case of refractory PIH treated with fractional CO2 laser.

Case Report
A 24-year-old woman with Fitzpatrick skin type III presented to the outpatient clinic with a six-year history of a brown patch on the left side of the face (Figure 1). She stated that the pigmentation occurred after waxing the hairs on the cheek. She had been using several topical treatments, including hydroquinon 4%, tretinoin, arbutin, and vitamin C and daily sunscreen for years without any improvement. She was diagnosed with PIH and laser treatment was recommended. Test spots of Q-switched Nd:YAG (Trivantage, Candela, Wayland, Massachusetts; 1064nm, 3mm spot, 3J/cm2, and 532nm, 2mm spot, 4J/cm2) and fractional CO2 laser (Quadralase, Candela; 300-micron handpiece, 8W energy, 20% coverage, 3.5msec pulse duration) were performed at the lateral border of the lesion. The test areas were evaluated at the second week, and fractional CO2 laser was the treatment of choice regarding the lightening at the test area.
Fractional CO2 laser with 300-micron handpiece, 8 to 10W energy, 20% coverage, and 3.5msec pulse duration was performed. One hour before the laser treatment, the area was cleaned and topical anesthetic was applied. After the treatment, the patient was strictly instructed to be gentle to the treated area and preserve the superficial crusts at least seven days after the procedure. Twice-daily topical application of mupirocine ointment was the only care after the laser treatment. After two treatment sessions with a one-month interval, the lesion totally cleared without any complication (Figure 2). The patient was advised to continue the application of broad-spectrum SPF 50 sunscreen.

Discussion
Fractional photothermolysis is a recent technology that creates vertical columns of thermal injury by fractional emission of light into microscopic treatment zones in a pixilated fashion. Hantash et al[5] demonstrated that after fractional photothermolysis, the degenerated dermal content incorporates into the microepidermal necrotic debris through a compromised dermoepidermal junction, which is then shuttled up to the epidermis to be exfoliated through the stratum corneum. This transepidermal elimination of the dermal content is the possible mechanism by which the melanin is eliminated in the treatment of pigmentary lesions with fractional photothermolysis.[2]

There are few reports in the literature regarding the efficacy of different laser systems in the treatment of PIH. Katz et al[2] have reported a case of PIH treated with three sessions of 1550nm fractional erbium-doped laser and achieved near-complete clearing seven months after the third treatment.[2] Rokhsar et al[3] demonstrated that 1550nm fractional erbium-doped laser was effective to treat the PIH of a patient who had previously undergone CO2 laser resurfacing and developed PIH.[3] Cho et al[4] have reported successful results with the use of low-energy Q-switched Nd:YAG laser in three cases of PIH that developed after different laser applications. However, in a recent report by Kroon et al,[6] 1550nm fractional erbium-doped laser was shown to be ineffective in PIH in a small number of patients.

Although it is much less frequent compared to other ablative lasers, PIH is observed in 1 to 32 percent of patients as a complication with fractional ablative lasers. The system used, the parameters, and the skin type of the patient have been considered important factors in the development of PIH after fractional ablative lasers.[7] The presented case was Fitzpatrick skin type III, and the authors used very conservative laser settings in order to prevent substantial PIH. From their previous experience with fractional ablative lasers, they believe that the crusts protect the wound and help to prevent PIH development after laser treatment. In general, with the regular measures of post-laser care, the epithelization is completed within 3 to 4 days and the crusts fall off, leaving an erythematous base. When the peeling phenomenon occurs a few days later in the healing period, this intense erythematous base is not observed. Takiwaki et al[8] revealed that the degrees of erythema and pigmentation correlated linearly after ultraviolet (UV) B irradiation, and their findings implied that the intensity of the inflammation correlated with the degree of PIH. The authors agree with the aforementioned study that the development of PIH correlates with the presence of erythema. Therefore, while treating pigmented disorders with ablative fractional lasers, it is necessary to avoid early removal of the crusts in order to prevent PIH development.

Topical bleaching creams and sunscreen with broad-spectrum UVA and UVB protection should be the first-line treatment for PIH.[1] However, in cases resistant to treatment, various laser systems can be used. Although PIH can be seen as a complication of many laser systems, including fractional CO2 laser, they also can be very successful tools by using appropriate parameters and by providing good care after laser treatment.

References
1.     Callender VD, St Surin-Lord S, Davis EC, Maclin M. Postinflammatory hyperpigmentation: etiologic and therapeutic considerations. Am J Clin Dermatol. 2011;12:87–99.
2.    Katz TM, Goldberg LH, Firoz BF, Friedman PM. Fractional photothermolysis for the treatment of postinflammatory hyperpigmentation. Dermatol Surg. 2009;35:1844–1848.
3.    Rokhsar CK, Ciocon DH. Fractional photothermolysis for the treatment of postinflammatory hyperpigmentation after carbon dioxide laser resurfacing. Dermatol Surg. 2009;35:535–537.
4.    Cho SB, Park SJ, Kim JS, et al. Treatment of post-inflammatory hyperpigmentation using 1064-nm Q-switched Nd:YAG laser with low fluence: report of three cases. J Eur Acad Dermatol Venereol. 2009;23:1206–1207.
5.    Hantash BM, Bedi VP, Sudireddy V, et al. Laser-induced transepidermal elimination of dermal content by fractional photothermolysis. J Biomed Opt. 2006;11:411–415.
6.    Kroon MW, Wind BS, Meesters AA, et al. Non-ablative 1550nm fractional laser therapy not effective for erythema dyschromicum perstans and postinflammatory hyperpigmentation: a pilot study. J Dermatolog Treat. 2012;23:339–344.
7.    Metelitsa AI, Alster TS. Fractionated laser skin resurfacing treatment complications: a review. Dermatol Surg. 2010;36: 299–306.
8.    Takiwaki H, Shirai S, Kohno H, et al. The degrees of UVB-induced erythema and pigmentation correlate linearly and are reduced in a parallel manner by topical anti-inflammatory agents. J Invest Dermatol. 1994;103:642–646.