Cristina Zane, Rossana Capezzera, Alessandra Pedretti, Elena Facchinetti, Piergiacomo Calzavara-Pinton
Summary
Background: During the past few years, various phototherapeutic protocols with full spectrum visible light or selected wavebands have been investigated in the treatment of
acne vulgaris with variable results.
Methods: Fifteen women suffering from moderate acne vulgaris of the face were exposed to 20 J/cm2 of broad-band red (l: 600–750 nm) light twice weekly for 4 weeks. In addition,
with the aim to improve the present knowledge of the mechanisms of action of phototherapy, we measured skin sebum, pH, hydration and trans-epidermal water loss
(TEWL). Lesions of the trunk were not irradiated and served as controls.
Results: A significant improvement of acne lesions and a significant decrease of skin sebum excretion and TEWL of the face were registered at the end of the therapy and at the 3-month follow-up visit. The results could be related to a reduced follicular colonization of Propionibacterium acnes, in that it was lethally damaged by photoactivated endogenous porphyrins.
Conclusion: The present findings seem to indicate that red light phototherapy may represent an effective, well-tolerated, safe, simple and inexpensive treatment option for moderate acne vulgaris.
Key words:
Acne vulgaris; non-invasive diagnostic techniques; phototherapy; Propionibacterium acnes; visible light