* Only erosions may be present in patients in whom blister(s) have recently ruptured.
¶ Refer to additional UpToDate content on the approach to cutaneous blisters.
Δ Refer to additional UpToDate content on specific disorders for details on diagnostic techniques. Additional disorders may be in the differential.
◊ Congenital erythropoietic porphyria and variegate porphyria are rare forms of porphyria that may present with similar cutaneous findings as porphyria cutanea tarda.