A 52-year-old man presents with recurrent, itchy, red papules and vesicles after sun exposure. What are these lesions and how would you treat them?
A 52-year-old man gave a six-year history of recurrent, itchy, red papules and vesicles which developed each spring after sun exposure. The eruption was concentrated over the sun-exposed sites on his face, sides of the neck (Figure 1), upper trunk and forearms. The lesions appeared after several hours of sun exposure and would settle after several weeks. Skin biopsy showed marked subepidermal oedema with perivascular lymphocytic inflammation in the upper and mid dermis (Figure 2).