ABSTRACT
BACKGROUND: Hereditary angioedema due to the Thr328Lys variant in the coagulation factor XII (HAE-FXII) affects mainly women in whom the symptomatology is dependent on high estrogen levels. Clinical variability and incomplete penetrance are challenging features that hinder the diagnosis and management of HAE-FXII. The c.-4T>C Kozak polymorphism is the only common variation accounting for FXII plasma levels and was previously shown to modify the course of HAE due to C1-Inhibitor deficiency. OBJECTIVES: To assess the influence of the c.-4T>C polymorphism on disease expression in 39 Spanish HAE-FXII index patients. METHODS: The c.-4T>C polymorphism was sequenced by the standard Sanger method, and HAE severity was calculated according to the score by Cumming et al. (2003) The activation of the contact system was quantified by the kallikrein-like activity of plasma in chromogenic assays upon activation with high-molecular-weight dextran sulfate. RESULTS: The c.-4CC genotype was overrepresented in the studied cohort: 82% were CC-homozygous (expected frequency = 59%) and 18% were CT-heterozygous (expected frequency = 39%) (p = 0.001). Patients with a c.-4CC genotype exhibited higher kallikrein-like activity (0.9659 ± 0.1136) than those with a c.-4TC genotype (0.7645 ± 0.1235) (p = 0.024) or healthy donors. Moreover, the polymorphism influenced HAE-FXII severity score (c.-4CC = 4.43 ± 2.28 vs c.-4TC = 2.0 ± 1.15; p = 0.006) but not the degree of estrogen dependence or time until remission. CONCLUSION: The c.-4T>C polymorphism is overrepresented in a Spanish HAE-FXII cohort and significantly influences the degree of contact system activation and the clinical severity of the disease.
ABSTRACT
INTRODUCTION: Hereditary angioedema is a disease with low prevalence and high heterogeneity with regards to the severity of the clinical picture, which makes the diagnosis difficult and requires the need for early start of specific treatment in order to prevent complications. OBJECTIVE: To propose a decision algorithm for hereditary angioedema (HAE), based on the evidence available on the diagnosis, clinical assessment, and treatment. The aim is to present the available therapeutic options as well as a decision algorithm to select the most efficient therapy at each time. MATERIAL AND METHODS: Literature search by means of PubMed and other relevant sources. RESULTS: four decision algorithms have been developed for HAE; diagnosis of bradikinin-mediated angioedema, treatment of acute attacks and short and long-term prophylaxis for HAE due to C1 inhibitor deficiency. CONCLUSIONS: The application of a decision algorithm based on the clinical variables helps to select the most efficient therapeutic option at each time and may be a useful tool for the therapeutic approach.
Introducción: El angioedema hereditario es una enfermedad rara de baja prevalencia y gran heterogeneidad en la gravedad del cuadro clínico, lo que dificulta su diagnóstico, y establece la necesidad de iniciar un tratamiento precoz y específico con el fin de evitar complicaciones. Objetivo: Proponer un algoritmo de decisión en el angioedema hereditario (AEH), basado en la evidencia disponible, sobre el diagnóstico, valoración clínica y tratamiento. Se trata de presentar opciones terapéuticas disponibles, así como un algoritmo de decisión para seleccionar el tratamiento más eficiente en cada momento. Material y Métodos: Revisión bibliográfica mediante una búsqueda a través de PubMed y otras fuentes de interés. Resultados: Se han desarrollado cuatro algoritmos de decisión para el AEH; diagnóstico de angioedema mediado por bradicinina, tratamiento del ataque agudo y profilaxis a corto y largo plazo del AEH por déficit del inhibidor C1. Conclusiones: La aplicación de un algoritmo de decisión, en función de unas variables clínicas, ayuda a la selección de la opción terapéutica más eficiente en cada momento y puede ser un instrumento de utilidad en el abordaje terapéutico.
