<unk>  is clinically characterized by increased skin fragility; erythema; and the appearance of tense bullae and erosions on sun-exposed skin, which are identical to those seen in patients with PCT. However, a clinical pearl that may prove helpful in differentiating between<unk>  and PCT is that the classic features of hypertrichosis, hyperpigmentation, and sclerodermoid changes found with PCT are unusual with<unk> . A second clinical pattern of<unk>  has a similar presentation to erythropoietic protoporphyria (EPP), an autosomal dominant porphyria resulting from a reduced activity of ferrochelatase. In contrast to PCT, EPP usually begins in childhood with a history of photosensitivity, often described as a burning sensation immediately after sunlight exposure. Clinically, EPP is characterized by erythema, edema, shallow scars, and waxy induration of the skin, particularly on the face.<unk>  that clinically mimics EPP has been described almost exclusively in children taking naproxen for juvenile rheumatoid arthritis. Naproxen-induced<unk>  seems to have a dimorphic presentation with the PCT-like pattern more often seen in the adult population and the EPP-like pattern more commonly seen in children, although some overlap has been documented. Race Although<unk>  has no predilection toward any one race, it has been shown that fair-skinned children who are highly prone to sunburn are more likely to develop naproxen-induced<unk>  than those children with skin types III or higher. Wallace et al. demonstrated that even in the absence of a history of blistering, children with light skin and blue or green eyes are at an increased risk of developing shallow scars on the face while taking naproxen.
Pseudoporphyria
Harderoporphyria
Erythropoietic protoporphyria
Porphyria
Scurvy
Megavitamin-B6 syndrome
Hemosiderinuria
Hepatic porphyria