RESUMEN
BACKGROUND: Literature on the efficacy of phototherapy in steroid-dependent antihistamine-refractory chronic urticaria (CRU) is limited. OBJECTIVES: To assess and compare the efficacy of psoralen plus ultraviolet A (PUVA) and narrowband ultraviolet B (NB-UVB) in steroid-dependent CRU. METHODS: In this randomized, prospective observer-blinded comparative study, 50 patients with steroid-dependent CRU (6 months of spontaneous urticaria with no response after 3 consecutive months of antihistamines and steroid dependence) were administered either PUVA (group A) or NB-UVB (group B) for 90 days, with a post-treatment follow-up of 90 days. The treatment efficacy was assessed using the average urticaria activity score 7 (aUAS7) and outcome scoring scale (OSS) every 2 weeks. RESULTS: The mean values of aUAS7 progressively decreased from 4·9 ± 0·8 and 5·0 ± 0·7 at baseline to 1·9 ± 0·7 and 1·4 ± 0·7 in groups A and B, respectively, by day 90. This further decreased to 1·5 ± 0·8 and 1·4 ± 1·0 at day 180 in both groups. The values of OSS progressively increased from baseline (1·6 ± 0·5 in group A and 1·3 ± 0·5 in group B) to 3·9 ± 0·3 and 4·0 ± 0·3 in groups A and B, respectively, by day 90, and 3·9 ± 0·5 and 4·0 ± 0·6 by day 180. NB-UVB fared statistically better than PUVA at different time points. Adverse events encountered were minimal and did not warrant treatment discontinuation. CONCLUSIONS: Phototherapy, especially NB-UVB, is an effective, safe and affordable therapeutic modality for steroid-dependent CRU and should be tried prior to third-line treatment options such as omalizumab, ciclosporin and other immunosuppressants.