A 20-year-old man presented with a 3-month history of a viral
wart located on his right thumb.
Cryotherapy was administered weekly to the
wart over 5 months without any significant improvement. A decision was made to treat the
wart with
red light photodynamic therapy (
PDT) using topical methyl aminolevulinate (MAL) administered as three treatments 1-week apart. The patient was reviewed 4 weeks after the third treatment and the
wart was found to have cleared completely. Three months after the last treatment, there remained no clinical evidence of recurrence of the
wart.
Pain was the main problem with the treatment but it was tolerable. Although the successful treatment of recalcitrant acral viral
warts with
PDT using 5-aminolevulinic
acid (ALA) is well documented, this is the first report of the successful
PDT treatment of a recalcitrant acral viral
wart using the methylester derivative of ALA. We believe that MAL is a valuable alternative
photosensitizer to ALA as it is more lipophilic, has better penetration and causes less
pain.