Recalcitrant hand and foot warts successfully treated with photodynamic therapy with topical 5-aminolaevulinic acid: a pilot study

The purpose of this pilot study was to determine if photodynamic therapy with topical application of 5-aminolaevulinic acid followed by irradiation with incoherent filtered and unfiltered light (ALA-PDT) is an effective therapy for recalcitrant hand and foot warts. In 30 patients with recalcitrant warts, 49 regions with a total of 250 warts were randomized to one of the following five treatments: (i) ALA-PDT with white light applied three times within 10 days (W3); (ii) ALA-PDT with white light applied once (W1); (iii) ALA-PDT with red light applied three times within 10 days (R3); (iv) ALA-PDT with blue light applied three times within 10 days (B3), and (v) cryotherapy applied up to four times within 2 months (CRYO). The ALA-PDT treatment modality was repeated in case of partially responding warts. Significantly more warts were completely healed after W3 and W1 than after R3, B3 and CRYO (P < 0.01): 73% of the warts treated with W3 were completely healed, 71% after W1, 42% after R3, 23% after B3 and 20% after CRYO. No scars were observed in the ALA-PDT treated areas and patients treated for foot warts were all able to walk after the treatment. No recurrences in completely responding ALA-PDT treated warts were observed after 12 months of follow-up. In conclusion, photodynamic therapy with topical 5-aminolaevulinic acid followed by irradiation with white light is a promising treatment for recalcitrant hand and foot warts.