Relación entre la sensibilización a camarón y ácaros. Exploración de la reactividad cruzada por tropomiosina

Abstract

RESUMEN: Antecedentes: Se conoce poco sobre la sensibilización a camarón en pacientes con alergias respiratorias sensibilizados a ácaros y la importancia clínica de dicha sensibilización en el trópico. Objetivos: Determinar la prevalencia de sensibilización a camarón en pacientes con rinitis o asma sensibilizados a ácaros, explorar la ruta de sensibilización, su relevancia y el papel de la sensibilización a tropomiosina. Métodos: Estudio de corte transversal en pacientes con asma y rinitis sensibilizados a ácaros. Mediante encuesta se indagó consumo de camarón y control del asma o rinitis. Se realizaron pruebas de provocación oral con camarón a los individuos sensibilizados a ácaros y camarón sin consumo, o con consumo mayor a seis meses, sin historia de reacción. En un subgrupo se midió la sIgE para camarón, Der p y Lit v 1. Se compararon los pacientes sensibilizados a ácaro y camarón (casos) y los sensibilizados solo a ácaros (controles). Resultados: De 229 pacientes, 48 (21 %) se encontraban sensibilizados a camarón. No hubo diferencia estadísticamente significativa en la ingesta de camarón entre casos (54.2 %) y controles (49.7 %); ocho casos presentaron síntomas al contacto con camarón. No se encontraron diferencias estadísticamente significativas en la sIgE para Der p, Lit v1 y camarón entre casos y controles. Se observó cambio mediano en la magnitud de efecto: 0.45, 0.44 y 0.41, respectivamente. Conclusiones: La sensibilización a camarón en pacientes con asma o rinitis alérgica por ácaros es alta, en 25 % parece ser clínicamente relevante, principalmente en aquellos con asma. La ingesta no es la principal vía de exposición a la tropomiosina; la reactividad cruzada puede explicar la frecuencia de sensibilización.

ABSTRACT: Background: Little is known out the sensitization to shrimp in patients with respiratory allergies who are sensitized to mites and about the clinical relevance of that sensitization in the tropical region. Objectives: To determine the prevalence of sensitization to shrimp in patients with rhinitis or asthma who are sensitized to mites, to explore the route of sensitization, its relevance, and the role of sensitization to tropomyosin. Methods: A cross-sectional study in patients with asthma and rhinitis who are sensitized to mites. Through a survey, it was asked about the consumption of shrimp and the control of asthma or rhinitis. Oral provocation tests were carried out with shrimp on individuals who are sensitized to mites and shrimp without consumption, or consumption greater than six months before, without reaction history. In a subgroup, the sIgE was measured for shrimp, Der p and Lit v 1. The patients who are sensitized to mites and shrimp (cases) were compared to the patients who are sensitized only to mites (controls). Results: Out of 229 patients, 48 (21%) were sensitized to shrimp. There wasn't a statistically significant difference in the intake of shrimp between cases (54.2%) and controls (49.7%); eight cases showed symptoms on contact with shrimp. No statistically significant differences were found in the sIgE for Der p, Lit v1 and shrimp between cases and controls. A medium change was observed in the size of the effect: 0.45, 0.44 and 0.41 respectively. Conclusions: Sensitization to shrimp in patients with asthma or allergic rhinitis caused by mites is high; in 25% it seems to be clinically relevant, mainly in those with asthma. Intake is not the main route of exposure to tropomyosin; cross-reactivity can explain the frequency of sensitization.