RESUMO
Phytophotodermatitis is a type of contact dermatitis that occurs upon skin exposure to certain plant chemicals, known as furocoumarins, along with simultaneous sun exposure. This case details a 34-year-old patient who presented to the office with an asymptomatic, irregularly shaped, and hyperpigmented patch located on the left inferior middle back that had been present since a recent beach vacation in Mexico. Upon gathering the history, clinicians should inquire about recent sunlight exposure while consuming and/or touching phytotoxic plant derivatives found in most citrus plants. The history should correspond with the skin examination findings and conclude that a cutaneous phytotoxic reaction had occurred when a lime margarita contacted the hand, which was subsequently rubbed onto the patient's back. This case highlights the importance of both taking a thorough history and physical examination and being aware of the broad range of skin manifestations to prevent unnecessary treatment, such as topical corticosteroids, for other skin disorders (the irregular presentation of atopic dermatitis, allergic contact dermatitis, and dermatitis unspecified) or improperly suspected child abuse in younger patient presentations.
RESUMO
La fitofotodermatitis es una enfermedad fototóxica caracterizada por la exposición de la piel a agentes fotosensibles (furocumarinas) que cambian su configuración en presencia de luz UV-A, resultando en daño cutáneo de magnitud variable según condiciones ambientales del huésped. Se identificó las plantas que contienen furocumarinas y se buscó su presencia en Isla de Pascua. Se encontraron cuatro especies en la vegetación de Isla de Pascua que están relacionadas con la fitofotodermatitis: Apium graveolens (apio), Daucus carota (zanahoria), Ficus carica (higuera y Citrus limon (limonero). El apio y la zanahoria se distribuyen principalmente en plantaciones rurales, mientras la higuera se encuentra distribuida en numerosos lugares urbanos y rurales de la isla, y el limonero está presente en sitios que reciben baja afluencia de turistas. La exposición cutánea a bebidas alcohólicas preparadas con cítricos y luz UV-A también pueden causar la patología.
Phytophotodermatitis is a phototoxic disease characterized by skin exposure to photosensitizing agents (furocoumarins), which change their configuration when exposed to UV-A ligth, resulting in variable skin damage according to environmental and host conditions. Plants containing forocoumarins were searched in Easter Island. Four species were identified in Easter Island s vegetation related with phytophotodermatitis: Apium graveolens (celery), Daucus carota (carrot), Ficus carica (fig tree) and Citrus limon (lemon tree). The celery and the carrot are distributed in numerous urban and rural plantations, the fig tree is distributed in numerous urban and rural places of the island, while the lemon tree is present in sites that receive few tourists. The skin exposition to alcoholic drinks prepared with citrus fruits plus UV-A light can also cause the disease.
Assuntos
Humanos , Dermatite Fotoalérgica/etiologia , Furocumarinas , ChileRESUMO
OBJECTIVE: To examine the epidermis in induced phytophotodermatitis using transmission electron microscopy in order to detect histologic changes even before lesions are visible by light microscopy. INTRODUCTION: In the first six hours after the experimental induction of phytophotodermatitis, no changes are detectable by light microscopy. Only after 24 hours can keratinocyte necrosis and epidermal vacuolization be detected histologically, and blisters form by 48 hours. METHODS: The dorsum of four adult rats (Rattus norvegicus) was manually epilated. After painting the right half of the rat with the peel juice of Tahiti lemon, they were exposed to sunlight for eight minutes under general anesthesia. The left side was used as the control and exposed to sunlight only. Biopsies were performed immediately after photoinduction and one and two hours later, and the tissue was analyzed by transmission electron microscopy. RESULTS: No histological changes were seen on the control side. Immediately after induction, vacuolization in keratinocytes was observed. After one hour, desmosomal changes were also observed in addition to vacuolization. Keratin filaments were not attached to the desmosomal plaque. Free desmosomes and membrane ruptures were also seen. At two hours after induction, similar changes were found, and granular degeneration of keratin was also observed. DISCUSSION: The interaction of sunlight and psoralens generates a photoproduct that damages keratinocyte proteins, leading to keratinocyte necrosis and blister formation. CONCLUSIONS: Transmission electron microscopy can detect vacuolization, lesions of the membrane, and desmosomes in the first two hours after experimental induction of phytophotodermatitis.
Assuntos
Animais , Ratos , Dermatite Fototóxica/patologia , Desmossomos/ultraestrutura , Epiderme/ultraestrutura , Microscopia Eletrônica de Transmissão/normas , Vesícula/induzido quimicamente , Vesícula/patologia , Citrus , Modelos Animais de Doenças , Eritema/induzido quimicamente , Eritema/patologia , Frutas , Necrose/induzido quimicamente , Necrose/patologiaRESUMO
Brazilian flora is very rich and a large number of specimens can cause adverse reactions, from mild erythema to cutaneous necrosis. Plants or vegetal extracts are always suspected of contact dermatitis; they are found in all types of environments, including dwellings. Other harmful effects, which can be identified by clinical manifestations and the aid of the patient, are phytophotodermatitis, traumas, thorn infections, chemical irritations, or urticaria caused by Urtica sp. Knowledge on the most important plants and their effects on human skin are very useful, and diagnosis is very important in treatment of the complications.