Purpuric lesions induced by UVA1 spectrum (340-400 nm) phototesting in an adult with persistent and severe hydroa vacciniforme.

A 28-year-old man had presented a severe photosensitivity since his infancy. In March 2008, the clinical examination showed large crusts on the dorsum of his hands, on the edge of his ears with destruction of the underlying cartilage, and on his nose and cheeks. He also presented erythematosus fibrous scars on the temples. The diagnosis of hydroa vaccinforme was made. Phototesting including repeated UVA1 phototest was strongly positive with purpuric lesions from day 7 to day 10 and hypertrophic scars at day 67. A sequential histological study of the UVA1 triggered lesions was performed and showed bullous cleavage, dense inflammatory infiltrate in the whole dermis with numerous neutrophilic cells, nuclear dusts, superficial focal thrombosis of small blood vessels at day 10. We report an unusual case of hydroa vaccinforme with purpuric lesions leading to fibrous scars and with important infiltration of neutrophils in the dermis of the photoinduced lesions.