Photodynamic therapy with methyl 5-aminolevulinate acid combined with microneedle treatment in patients with extensive alopecia areata

Conflict of interest: none declared. Alopecia areata (AA) is a nonscarring, autoimmune and inflammatory hair‐loss condition of the scalp and/or body. Extensive AA is often refractory. Recently, photodynamic treatment (PDT) has been considered as a new therapeutic option for extensive AA. In many previous trials, the effectiveness of PDT for AA has been controversial.1–3 One group suggested that the absence of fluorescence under microscopy in the inflammatory infiltrates around hair follicles after application of photosensitizers might explain the absence of significant hair growth in their study.3 We hypothesized that the failure of treatment with PDT in previous studies was due to malabsorption of the photosensitizer. The microneedle treatment system (MTS) can easily create numerous transdermal microchannels, and has been used to enhance drug delivery.4 Therefore, we examined the synergistic effects of the combination of MTS and methyl 5‐aminolevulinic acid (MAL)‐PDT for the treatment of extensive AA. Six patients with static AA were enrolled. All patients had previously received other treatments, but with no benefit. All previous treatments were stopped at least 1 month before beginning PDT. Before PDT treatment, an area was prepared on the right side of an alopecia totalis (AT) area on the scalp, using a roller with 1 mm microneedles (DTS LAB, French Beauty, Seoul, Korea) to improve absorption of the MAL cream. No rolling was performed on the left side. If there was only one affected area, treatment was given to only part of that area (the right side), with the untreated area serving as a control.