Niveles de anticuerpos anti nucleares por Fana y Ana-Lia en pacientes con enfermedades reumáticas sistémicas / Levels of anti-nuclear antibodies by Fana and Ana-Lia in systemic rheumatic diseases patients

Objetivo: Correlacionar los niveles de anticuerpos antinucleares obtenidos por las técnicas de inmunofluorescencia indirecta (FANA) e inmunoensayo lineal (ANA-LIA) en pacientes diagnosticados o con sospecha clínica de enfermedad autoinmune. Métodos: Se incluyeron 100 pacientes que dieron su consentimiento informado para participar en el estudio. Los ensayos e interpretación de los resultados de las pruebas de FANA y ANA-LIA se realizaron siguiendo las recomendaciones del fabricante. Resultados: el 97,4% de los pacientes estudiados eran de sexo femenino con edad promedio de 42 años, siendo la Artritis reumatoide, Poliartritis y Lupus Eritematoso Sistémico las enfermedades que con mayor frecuencia acompañaron la solicitud médica. Se observó que ambos métodos fueron positivos en el 21% de los casos y que el indice de correlaciòn de Kappa entre las pruebas fue moderado (k= 0,51; p< 0,05), la sensibilidad y especificidad de los métodos fue del 71,4% y 84,8% respectivamente, se observó también que para un determinado patrón fluorescente puede haber positividad de más de un antígeno de la prueba de ANA-LIA y viceversa. Conclusiones: FANA es el método de tamizaje aceptado en la práctica clínica para orientar hacia un diagnóstico clínico de enfermedad autoinmune más probable, debido a la subjetividad en la interpretación de sus resultados y necesidad de entrenamiento en la identificación de los patrones fluorescentes, se requiere del apoyo de otros métodos de laboratorio que permitan identificar con mayor precisión los antígenos reconocidos por los autoanticuerpos, ANA-LIA es una herramienta de laboratorio costo-efectiva de elevada sensibilidad y especificidad que se ajusta a este requerimiento.

Objective: To correlate levels of antinuclear antibodies obtained by indirect immunofluorescence techniques (FANA) and linear immunoassay (ANA-LIA) in patients diagnosed or with clinical suspicion of autoimmune disease. Methods: 100 patients who gave their informed consent to participate in the study were included. Assays and interpretation of results of FANA and ANA-LIA test were performed following the manufacturer's recommendations. Results: 97,4% of the patients studied were female with an average age of 42 years, being rheumatoid arthritis, polyarthritis and systemic lupus erythematosus the diseases that most frequently accompanied the medical request. It was observed that both methods were positive in 21% of the cases and that the Kappa correlation index was moderate between the tests (k = 0,51; p <0,05), the sensitivity and specificity of the methods was 71,4% and 84,8% respectively. It was also observed that for a given fluorescent pattern there may be positivity of more than one antigen of the ANA-LIA test and vice versa. Conclusions: FANA is the screening method accepted in the clinical practice to guide towards a more probable clinical diagnosis of autoimmune disease. Due to the subjectivity in the interpretation of its results and the need for training in the identification of fluorescent patterns, the support of other laboratory methods that allow the identification of antigens recognized by autoantibodies with greater precision is necessary, ANA-LIA is a cost-effective laboratory tool of high sensitivity and specificity that meets this requirement.

Analysis of the results of antinuclear antibody and anti-ENA antibodies for 297 patients of autoimmune diseases with IIF and biochip technology / 国际检验医学杂志

Objective To analyze the clinical features and significance of the samples which the expression of ANA is positive and the expression of anti‐ENA antibody is negative .Methods Detect ANA and anti‐ENA antibody of all the 297 samples by indi‐rect immunofluorescence method and biological chip technology ,repectively .And analyze the fluorescence karyotype of ANA posi‐tive specimens with double‐blind method .Screen the samples which anti‐ENA antibody express negative from ANA positive sam‐ples .Compare and analyze the fluorescent karyotype .Results Of all the 297 samples ,74 cases were positive for ANA ,the positive rate was 24 .9% (74/297) .The majority of patterns were speckled pattern (43 cases ,58 .1% ) ,cytoplasmic granular pattern (9 ca‐ses ,12 .2% ) ,and antibody to centromere antigen(9 cases ,12 .2% ) ,respectively .In 74 cases of ANA positive specimens ,ENA anti‐body the negative rate of ENA antibody is 17 .6% (13/74) .Of the 13 cases ,the most frequently occurred pattern was the speckled pattern(11 cases ,84 .6% ) ,the rate of cytoplasmic granular pattern and antibody to centromere antigen was 7 .7% (1/13) respec‐tively .Conclusion In the serum samples which express ANA positive and ENA antibody negative ,the rate of speckled pattern is significantly higher than the other patterns ,and far more than the rate of speckled pattern in the samples which express ENA anti‐body and ANA positive (52 .5% ) (chi‐square= 5 .018 ,P< 0 .05) ,with statistical significance .We consider the speckled pattern samples be in favour of discovering new antibodys of this kind of serum sample .