Topical photodynamic therapy with 5-aminolaevulinic acid does not induce hair regrowth in patients with extensive alopecia areata
Article first published online: 27 AUG 2008
British Association of Dermatologists, 2000
British Journal of Dermatology
Volume 143, Issue 5, pages 1032–1035, November 2000
How to Cite
Bissonnette, R., Shapiro, J., Zeng, H., Mclean, D.I. and Lui, H. (2000), Topical photodynamic therapy with 5-aminolaevulinic acid does not induce hair regrowth in patients with extensive alopecia areata. British Journal of Dermatology, 143: 1032–1035. doi: 10.1046/j.1365-2133.2000.03783.x
- Issue published online: 27 AUG 2008
- Article first published online: 27 AUG 2008
- Accepted for publication 18 May 2000
- 5-aminolaevulinic acid;
- alopecia areata;
- photodynamic therapy
Background Photodynamic therapy (PDT) is a new modality involving the administration of a photosensitizer, or photosensitizer precursor, followed by its activation with light to generate a therapeutic effect. 5-Aminolaevulinic acid (ALA) is a photosensitizer precursor that is transformed by cells into protoporphyrin IX (PpIX), which can in turn be activated by red light.
Objectives To investigate the effect of PDT in alopecia areata (AA).
Methods In six patients with extensive AA, topical ALA lotion at 5%, 10% and 20% as well as the vehicle lotion alone were applied separately to different scalp areas, followed 3 h later by exposure to red light at each treatment session.
Results No significant hair growth was observed after 20 twice-weekly treatment sessions. A significant increase in erythema and pigmentation was observed for the three concentrations of ALA lotion vs. the vehicle, implying that a phototoxic PDT effect was achieved in the skin. In vivo fluorescence spectroscopy in one patient showed an increase in red PpIX fluorescence 3 h after ALA application followed by a decrease after light exposure. On fluorescence microscopy, bright red fluorescence was present in the epidermis and sebaceous glands, but not in the inflammatory infiltrate surrounding the hair follicle following ALA application.
Conclusions PDT was ineffective in the treatment of AA.