Photodynamic therapy for nail disorders: our experience
Donnarumma M, Annunziata MC, Fabbrocini G
Division of Clinical Dermatology Department of Clinical Medicine and Surgery, University of Naples Federico II
Background: Photodynamic Therapy (PDT) is a non-invasive therapy that utilizes light to activate a photosensitizing agent applied topically or systemically, which generates reactive oxygen species (ROS) that initiate the destruction of cells by necrosis or apoptosis. Photosensitizers (PSs) act by absorbing energy from ultraviolet or visible light and transferring it to adjacent molecules. According to International guidelines, it is indicated for the treatment of actinic keratosis, basal cell carcinoma and Bowen's disease. However, for its antimicrobial and localized action on different cell types, it has many fields of activity.
Methods: We studied different nails diseases sush as onychomycosis, nail psoriasis and periungual granuloma treated with PDT. Nails treated were previously occluded with methyl-aminolaevulinic acic (MAL) for 3 h using a bioadhesive patch. The nails were evaluated at baseline, and after 3 treatment, clinically and trough score disease.
•PDT can be a treatment option for longstanding onychomycosis that has not responded to the usual antifungal therapies or in patients with comorbidities and taking other medications. PDT does not interact with other drugs and can be combined with antifungal agents.
•What kind of photosensitizer? 20% ALA, 16% methyl-aminolevulinate (MAL), 2% methylene blue, hematoporphyrin derivative can be used. MAL/PDT has a similar efficacy to ALA/PDT.
•PDT can be an effective treatment for onychomycosis, regardless of the causative pathogen involved.
Protocol for Photodynamic Therapy in the Treatment of Onychomycosis.
•Apply 40% urea under occlusive dressing 12-24 h for three days before treatment
•Clean the urea residue from the nail plate. Apply the photosensitizer to the nail and periungual and cover the whole area for 3 h with 16% 5-methyl aminolevulinate acid . Irradiate with LED 635 nm. Repeat the procedure every 2 weeks for up to 3 sessions.
•Nail involvement affects 80–90 % of patients with plaque psoriasis, and is even more prevalent in patients with psoriatic arthritis
•The use of systemic therapies only for treatment of nail psoriasis is usually not justified
•According to our experience there are no statistically significant differences between the use of pdt and standard therapies in the treatment of nail psoriasis.
Periungual granuloma during chemotherapy
• Periungual granulomas appear as erythematous nodules covered by crusts, they are painful and associated with important functional limitations.
• They appear after a long period of treatment, usually 1-2 months with EGFR inhibitor (Cetuximab, Panitumumab, Erlotinib, Gefitinib)and ErbB inhibitor (Lapatinib, Pertuzumab, Afatinib).
•Treatments: diathermocoagulation, silver nitrate and phenol 8% - 16% - 88%.
•Possible application of PDT: selected areas of treatment, anti-inflammatory property, inhibition on endothelial cells and modulation of granulomatous processes.
Conclusion:Pdt has many possible fields of action on nail disorders with a small number of side effects and a localized action. It can be a therapeutic alternative in treatment of onomycycosis and periungual granuloma. But it’s important to define guidelines on type of photosensitizer, dosage, light type and vehicle for each pathology.