The Cutaneous Porphyrias
The porphyrias are a group of mainly inherited disorders of heme biosynthesis where accumulation of porphyrins and/or porphyrin precursors gives rise to 2 types of clinical presentation: cutaneous photosensitivity and/or…
Drug-Induced Photosensitivity
Drug-induced photosensitivity is common. The principal mechanism of systemic drug photosensitivity is phototoxicity and the principal mechanism of topical drug photosensitivity is photoallergy. Photopatch testing is helpful to determine suspected…
Chronic Actinic Dermatitis
Chronic actinic dermatitis (CAD) is an immunologically mediated photodermatosis characterized by pruritic eczematous and lichenified plaques located predominantly on sun-exposed areas with notable sparing of eyelids, skin folds, and postauricular…
Hydroa Vacciniforme and Solar Urticaria
Hydroa vacciniforme (HV) and solar urticaria (SU) are uncommon immunologically mediated photodermatoses. HV occurs almost exclusively in children, usually beginning in childhood and remitting spontaneously by adolescence. Association with chronic…
Actinic Prurigo
Actinic prurigo is a chronic photodermatosis with onset in childhood or before 20 years of age. It is most prevalent in Amerindians and Latin American mestizos, although it has been…
Polymorphous Light Eruption
Polymorphous light eruption is an immunologically mediated photodermatosis with high prevalence, particularly among young women in temperate climates, characterized by pruritic skin lesions of variable morphology, occurring in spring or…
Photocarcinogenesis
Photocarcinogenesis is the result of a complex interplay between ultraviolet radiation, DNA damage, mutation formation, DNA repair, apoptosis, and the immune system. Recent trends show an increase in incidence of…
Photoaging
This article discusses photoaging or premature skin aging from chronic ultraviolet exposure. This is an important cosmetic concern for many dermatologic patients. Clinical signs include rhytids, lentigines, mottled hyperpigmentation, loss…
Photoimmunology
The discipline that investigates the biologic effects of ultraviolet radiation on the immune system is called photoimmunology . Photoimmunology evolved from an interest in understanding the role of the immune…
Evaluation of Patients with Photodermatoses
The systematic evaluation of photosensitive patients involves a comprehensive history, physical examination, phototesting, and, if necessary, photopatch testing and laboratory evaluation. Polymorphous light eruption, chronic actinic dermatitis, solar urticaria, and…
