ABSTRACT
The aim of this work was to describe the epidemiological, clinical and pathological aspects of two outbreaks of spontaneous poisoning caused by Froelichia humboldtiana in cattle in Pernambuco, northeastern Brazil and reproduce experimentally this poisoning in cattle. Spontaneous poisonings of primary photosensitization occurred in two farms at the municipalities of Cachoeirinha and São Caetano and affected twenty-two adult bovines and two suckling calves after the rainy season. All bovines have recovered 21 days after they were removed from the pasture. To reproduce experimental poisoning, three cows and a calf were maintained in a pasture with 1ha composed by F. humboldtiana during 14 days. Clinical signs and skin lesions were similar in both spontaneous and experimental poisoning and consisted of cutaneous itching and hyperemia of non-pigmented areas of skin that evolved into edema, exudative dermatitis and extensive areas of skin necrosis. Serum levels of aspartate aminotransferase (AST), gamma glutamyltransferase (GGT), total, direct and indirect bilirubin were normal in all cattle examined. Histologically, lesions consisted of epidermal necrosis, hyperkeratosis with large amounts of degenerate neutrophils and acanthosis. In the dermis, edema and inflammatory infiltrate composed of eosinophils, lymphocytes and plasma cells mainly around the blood vessels were observed. In the experimental group, clinical signs of photosensitization were observed after the third day of F. humboldtiana consumption. The suckling calf displayed mild clinical signs of photodermatitis on the 8th day of the experiment. It was estimated that the average consumption of F. humboldtiana necessary to initiate clinical signs in each adult bovine was 78kg.(AU)
Os objetivos deste trabalho foram descrever os aspectos epidemiológicos, clínicos e patológicos de dois surtos de intoxicação por Froelichia humboldtiana em bovinos em Pernambuco e reproduzir experimentalmente essa intoxicação em bovinos. Intoxicações espontâneas foram observadas após o início do período chuvoso nos municípios de Cachoerinha e São Caetano. Vinte e dois bovinos apresentaram sinais clínicos e lesões cutâneas compatíveis com fotossensibilização primária, dentre os quais, dois bezerros lactentes. Todos os bovinos se recuperaram totalmente cerca de 21 dias após serem retirados da pastagem. Para reproduzir experimentalmente a intoxicação, três vacas, uma delas com bezerro ao pé, foram mantidas em um piquete de 1ha composto por F. humboldtiana por 14 dias consecutivos. O quadro clínico e as lesões tegumentares, tanto nos bovinos intoxicados nos surtos espontâneos, quanto nos bovinos do experimento consistiram em prurido e hiperemia em áreas despigmentadas de pele, que evoluíam para edema, dermatite exsudativa e necrose de áreas extensas de pele. Em todos os bovinos examinados, os níveis séricos de aspartato aminotransferase (AST), gamaglutamiltransferase (GGT), bilirrubina total, direta e indireta estavam normais. Histologicamente, as lesões consistiram em necrose da epiderme, hiperqueratose com grande quantidade de neutrófilos degenerados e acantose. Na derme havia edema e infiltrado inflamatório composto por eosinófilos, linfócitos e plasmócitos principalmente ao redor dos vasos sanguíneos. Nos bovinos do experimento, sinais clínicos de fotossensibilização foram observados após o terceiro dia de consumo de F. humboldtiana. O bezerro lactente apresentou sinais clínicos leves de fotodermatite no 8º dia do experimento. Estimou-se que o consumo médio de matéria seca de F. humboldtiana necessário para iniciar os sinais clínicos em cada bovino adulto foi de 78kg.(AU)
Subject(s)
Animals , Cattle , Plant Poisoning/veterinary , Dermatitis, Photoallergic/etiology , Cicer/poisoning , Cicer/toxicity , Dermatitis, Photoallergic/veterinary , Dermatitis/etiology , Dermatitis/veterinaryABSTRACT
Las fotodermatosis son un conjunto de patologías cutáneas originadas o agravadas por exposición a radiación ya sea solar o artificial. Se clasifican en cuatro categorías: 1. Idiopáticas o mediadas inmunológicamente 2. Dermatosis fotoagravadas, 3. Fotosensibilidad inducida por agentes y 4. Trastornos por reparación defectuosa del ADN. La fotosensibilidad inducida por agentes consiste en reacciones secundarias a la exposición de ciertos químicos, llamados fotosensibilizadores y a distintos tipos de radiación lumínica. Los fotosensibilizadores pueden ser de origen endógeno o exógeno, aquellos exógenos provienen desde el ambiente, fármacos u otros productos (tanto sistémicos como tópicos), los cuales sufren modificaciones estructurales al entrar en contacto con radiación, provocando como consecuencia, distintas manifestaciones cutáneas. En este artículo se revisarán principalmente las reacciones fototóxicas y fotoalérgicas (ambas, reacciones de fotosensibilidad inducidas por agentes exógenos) indagando en sus diferencias y el enfrentamiento clínico de cada una. También, se revisarán los exámenes que permiten estudiar los distintos diagnósticos diferenciales, especialmente el test de fotoparches, el cual está cobrando cada vez más importancia en la práctica clínica.
Photodermatoses are a group of skin diseases induced or aggravated by exposure to radiation, whether solar or artificial. They are classified into four general categories: 1. Idiopathic or immunologically mediated photodermatoses 2. Photoexacerbated dermatoses 3. Agent induced photosensitivity 4. DNA repair defects Photosensitivity induced by agents are secondary reactions to the exposure to some chemicals, called photosensitizers, and to different types of light radiation. Photosensitizers can be classified as exogenous or endogenous. Exogenous agents come from the environment, drugs or other products (both systemic and topical), which undergo structural changes when they come into contact with radiation, causing different skin manifestations as consequence. Differences between phototoxic and photoallergic reactions (both photosensitivity reactions induced by exogenous agents), the clinical approach of each one of them, and available tests that are used to make a diagnosis, especially, photo patch test will be reviewed in this article
Subject(s)
Humans , Male , Female , Patch Tests/methods , Dermatitis, Photoallergic/diagnosis , Dermatitis, Photoallergic/etiology , Photosensitizing Agents/adverse effects , Diagnosis, DifferentialABSTRACT
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.
Subject(s)
Humans , Dermatitis, Photoallergic/etiology , Furocoumarins , ChileABSTRACT
Estudio epidemiológico de cohorte con 1030 escolares de 4to. y 5to. grados de dos Municipios de la Ciudad Habana, diferenciados por el grado de exposición a la contaminación ambiental. Se realizaron pruebas funcionales respiratorias a una submuestra, de los alumnos (104 en cada Municipio) y se confeccionó un registro diario de morbilidad en cada aula. Se encontró un porciento mayor de pruebas positivas en los niños con antecedentes patológicos personales, residentes en la zona de mayor exposición. Se halló un riesgo relativo mayor que 1, en el asma bronquial y en la obstrucción nasal en el Municipio Cerro de mayor exposición, en relación al Municipio Habana del este, de menor exposición.