Phototherapy for different types of cutaneous porphyria: a case series and systematic review

Porphyrias are a group of rare metabolic disorders characterized by defects in heme synthesis. Cutaneous photosensitivity is a common manifestation, posing significant challenges in its management. Photo-hardening accomplished using narrow-band ultraviolet radiation (NB-UVB) has been evaluated in the setting of erythropoietic protoporphyria (EPP) in small case series; however, data is scarce regarding other types of porphyria. We aimed to assess the effect of NB-UVB treatment on patients with different types of cutaneous porphyria. A case series of five patients with cutaneous porphyria who were treated with NB-UVB is presented. In addition, a systematic review of studies evaluating porphyria patients treated with NB-UVB was conducted. As a low number of studies evaluating this treatment was expected, our primary outcome was to evaluate exacerbations following treatment and patients' satisfaction. This case series includes three patients with variegate porphyria (VP), one patient with porphyria cutanea tarda (PCT), and one with EPP. Four of five patients were satisfied and did not experience exacerbations following treatment; the fifth patient showed lower compliance but also experienced improvement. The systematic review included 22 patients (four studies): 20 with EPP, one with VP, and one with congenital erythropoietic porphyria (CEP). Of the combined 27 patients, 17 (65%) reported an improvement following treatment. The number of phototherapy sessions varied among patients. There was no record of exacerbations following treatment. The available data supports NB-UVB phototherapy as a safe and effective measure for reducing exacerbations in patients with EPP, PCT, and VP.