Phototherapy in the Treatment of Acne Vulgaris

Abstract

Acne vulgaris is a common dermatosis affecting 80% of the population. To date, different treatments have been used to manage this condition. Antibacterials and retinoids are currently the mainstay of treatment for acne, but their success rate varies. Phototherapy is emerging as an alternative option to treat acne vulgaris. Studies examining the role of different wavelengths and methods of light treatment have shown that phototherapy with visible light, specifically blue light, has a marked effect on inflammatory acne lesions and seems sufficient for the treatment of acne. In addition, the combination of blue-red light radiation seems to be superior to blue light alone, with minimal adverse effects. Photodynamic therapy has also been used, even in nodular and cystic acne, and had excellent therapeutic outcomes, although with significant adverse effects. Recently, low energy pulsed dye laser therapy has been used, and seems to be a promising alternative that would allow the simultaneous treatment of active acne and acne scarring. Further studies are needed to clarify the role of phototherapy as a monotherapy or an adjuvant treatment in the current management of acne vulgaris.

Blue and red light combination LED phototherapy for acne vulgaris in patients with skin phototype IV

“…It is the current consensus that acne is a multifactorial disease which involves four primary events; follicular hypercornification, increased sebum secretion, colonization of P. acnes, and inflammation [14]. Particularly, P. acnes is considered to play a key role in more than one way.…”

“…This reaction stimulates production of reactive free radicals and singlet oxygen species, which results in destruction of the bacteria [14][15][16][17][18][19][20][21][22][23]. Although the bacterial sensitivity to light becomes higher as the wavelength gets shorter, there exists a second absorption peak at 415 nm, which corresponds to that of coproporphyrin III, the predominant bacterial porphyrin produced by P. acnes [15,21,33,34].…”

“…Recently, it has been revealed that visible light activates the endogenous porphyrins of P. acnes, which results in a photodynamic reaction to destroy the bacteria [14][15][16][17][18][19][20][21][22][23]. The absorption peak of the bacterial porphyrins is at 415 nm, which falls into the blue light waveband [15].…”

Estudo clínico, prospectivo, aberto, randomizado e comparativo para avaliar a segurança e a eficácia da luz azul versus peróxido de benzoíla 5% no tratamento da acne inflamatória graus II e III

“…9,10 Nesse sentido, estudos têm demonstrado que a luz visível é uma modalidade alternativa e efetiva para tratamento da acne. [11][12][13][14][15] Esse resultado pode ser explicado pela produção de porfirinas, especialmente uropofirinas, coproporfirinas e protoporfirinas IX 16 pelo P. acnes. As protoporfirinas têm a capacidade de absorver luz e desse modo promover uma reação fotodinâmica que induz à destruição bacteriana.…”

“…Esse comprimento de luz é eficiente para a fotoestimulação das porfirinas, confor-me estudos in vitro e in vivo. [12][13][14][15][16][17] A penetração dessa luz é de aproximadamente 1 mm na pele, e portanto atinge o P. acnes que se encontra na sua superfície e no interior dos ductos. Os pacientes receberam proteção ocular com óculos de natação de lentes escuras Speedo ® durante as sessões.…”