Evaluación del prick test para detección de sensibilización alergénica en perros clínicamente compatibles con dermatitis atópica en la ciudad de Medellín

Abstract

RESUMEN: La dermatitis atópica canina es la enfermedad cutánea más prevalente en perros. El canino es la única especie que comparte una semejanza marcada con la dermatitis atópica humana. Una combinación de factores medio ambientales, genéticos e inmunológicos lleva a una disfunción crónica en la barrera cutánea junto con manifestaciones pruríticas e inflamatorias en la piel, que se agravan con infecciones oportunistas secundarias. Las vías inmunopatológicas en la dermatitis atópica canina son complejas y lo que comprendemos a la fecha es que no hay un único factor disparador de la enfermedad, sino una sumatoria de factores causales en el individuo que llevan a una presentación clínica en común. En la presentación de dermatitis atópica humana, se utiliza una variedad de métodos de identificación de los alérgenos causales de la enfermedad, siendo la prueba percutánea el método de elección en la actualidad. El objetivo de este trabajo de maestría es identificar los conceptos claves de la inmunopatogénesis de la dermatitis atópica canina con el fin de dilucidar futuras áreas de investigación. Los últimos hallazgos y conceptos sobre cada una de las células, citoquinas, quimiocinas y cofactors involucrados en la inmunopatogénesis de la dermatitis atópica canina son tratadas. De igual manera se realiza una investigación piloto donde se analiza la viabilidad de aplicar la prueba percutanea humana como herramienta en la identificación de los principales alergenos causales de la respuesta inmune en caninos con dermatitis atópica en la ciudad de Medellin.

ABSTRACT: Canine atopic dermatitis (AD) is defined as chronic, pruritic and inflammatory cutaneous disease that is present in genetically predisposed animals (Hensel et al., 2015a). Factors such as the environment, genetics and the individuals immune response join to generate a complex network of interactions that lead to the clinical manifestations of the disease. Canines are one of the few non-human species that develop cutaneous allergic diseases in a spontaneous manner (Pucheu-Haston, 2016) and it is estimated that 10% of the total population of dogs suffers from AD. The first reports of allergic disease in dogs dates to approximately 70 years, when hypersensitivity towards food and environmental allergens was described. According to those descriptions and to clinical characteristics between human and canine species, dogs have been used as animal models of AD for their human counterpart (Marsella & Olivry, 2003). The tight relationship that dogs and humans have had dates to over 32000 years where they have lived amongst the same spaces and have evolved together due to the environmental and sociocultural changes have shaped our current ways of life (Tsai et al., 2007). This implies that both species have been exposed simultaneously and synchronically to the same allergens that are found as causative agents of AD. What used to be considered as a Th2 type response in an acute phase and a Th1 response in a chronic phase in canine AD is now considered as a predominantly Th2 response in an acute state and a mixed response between Th1, Th2, Th17 and Th22 in a chronic state (Pucheu-Haston, Bizikova, Marsella, et al., 2015). Advances in knowledge and the comprehension of the pathogenesis of AD in humans as well as dogs has opened the doors of a wider, multimodal approach to the disease. The comprehension of the genetic, environmental, microbiologic, physical, biochemical, neurologic and cellular processes lead to the clinical presentation of AD, allowing a new understanding of the molecular interactions of the immune system and their implications for the patient in the short and long term. This thesis describes the immunopathological mechanisms known to date and future perspectives of canine AD while analyzing the prick test as a tool in the detection of the allergenic sensitization in this disease.