Evaluación del sistema Brucellacapt® para el diagnóstico serológico de la brucelosis humana en Cuba / Evaluation of the system Brucellacapt® for serological diagnosis of human brucellosis in Cuba

Introducción: En el diagnóstico microbiológico de la brucelosis, los métodos serológicos son los más utilizados. Brucellacapt® ofrece la ventaja de detectar en cualquier momento de la enfermedad anticuerpos aglutinantes y no aglutinantes contra Brucellaspp. Objetivos: Evaluar y aplicar el sistema serológico comercial Brucellacapt® para la detección de anticuerpos contra Brucella spp. Métodos: Se realizó una investigación en servicios y sistemas de tipo observacional con un estudio de caso control anidado, en el periodo de enero de 2015 a junio de 2016, en el Laboratorio Nacional de Referencia de Espiroquetas y Brucelas. Se evaluaron 50 sueros de casos y 100 de controles por Brucellacapt®. Se aplicó Brucellacapt® en 695 sueros de casos con sospecha clínica o epidemiológica de la enfermedad, los cuales fueron confirmados por ELISA. Resultados: Brucellacapt® mostró 100 por ciento de sensibilidad, 83 por ciento de especificidad, 54,6 por ciento de reactividad y 16,4 por ciento de positividad en las muestras estudiadas. Se confirmó por ELISA la presencia de anticuerpos IgM (21, 2 por ciento), IgG (6,1 por ciento) e IgM + IgG (7,6 por ciento). Doscientas cuarenta y seis muestras y otras siete fueron reactivas y positivas respectivamente, solo por Brucellacapt®. Conclusiones: Brucellacapt® contribuyó a la detección de anticuerpos en los sueros de pacientes sospechosos de la enfermedad con valores aceptables de sensibilidad y especificidad diagnóstica. Este resultado sugiere su implementación en la red nacional de laboratorios cubanos para fortalecer el diagnóstico y la vigilancia de la brucelosis humana en Cuba(AU)

Introduction: Serological methods are the most commonly used for the microbiological diagnosis of brucellosis. Brucellacapt® has the advantage of detecting agglutinating and non-agglutinating antibodies against Brucella spp. at any point in the evolution of the disease. Objectives: Evaluate and apply the commercially available serological system Brucellacapt® for detection of antibodies against Brucella spp. Methods: A nested case-control observational study was conducted of services and systems from January 2015 to June 2016 at the Spirochaete and Brucella National Reference Laboratory. Evaluation was performed of 50 serum samples from cases and 100 from controls using Brucellacapt®. The system was also used in 695 serum samples from clinically or epidemiologically suspected cases, which were confirmed by ELISA. Results: Brucellacapt® showed 100 percent sensitivity, 83 percent specificity, 54.6 percent reactivity and 16.4 percent positivity in the samples studied. Presence of the following antibodies was confirmed by ELISA: IgM (21.2 percent), IgG (6.1 percent) and IgM + IgG (7.6 percent). Two hundred forty-six samples and another seven were reactive and positive, respectively, only by Brucellacapt®. Conclusions: Brucellacapt® contributed to antibody detection in serum samples from suspected cases, with acceptable diagnostic sensitivity and specificity values. This result suggests its implementation in the Cuban national network of laboratories to strengthen the diagnosis and surveillance of human brucellosis in Cuba(AU)

Comparison of Brucellacapt and iELISA in serological diagnosis of brucellosis / 中国人兽共患病学报

Brucellacapt is a new serological test based on immunocapture-agglutination technique that has been used in many countries ,but there was no related article reported in China .The value of the Brucellacapt method in diagnosing human brucellosis was evaluated in this study .Among 120 suspected patients ,75 patients and 45 negatives were diagnosed by SAT and RBPT method combination with their clinical symptoms .Sera from all 120 people were tested by the method of Brucella-capt and iELISA ,and the results were ,consequently ,analyzed and compared .It showed that sensitivity ,specificity ,consis-tency rate ,Kappa value ,and area under ROC curve were found to be 82 .7% ,88 .9% ,85 .0% ,0 .69 ,and 0 .86 ,respectively for Brucellacapt ,whereas they were found to be 90 .7% ,64 .4% ,80 .8% ,0 .57 ,and 0 .78 for iELISA .In conclusion ,specific-ity ,consistency rate ,Kappa value ,and area under ROC curve were higher in Brucellacapt method than that in iELISA .How-ever ,the sensitivity of iELISA is higher .

Utilidad de la determinación de anticuerpos IgG e IgM por ELISA e inmunocaptura en una serie clínica de brucelosis humana / Usefulness of the determination of IgG and IgM antibodies by ELISA and immunocapture in a clinical series of human brucellosis

Introducción: El diagnóstico de brucelosis continúa siendo complejo en la actualidad y se requieren nuevas pruebas de diagnóstico. Objetivo: Evaluar pruebas comerciales para la determinación serológica de anticuerpos anti Brucella sp mediante ELISA e inmunocaptura en una serie clínica de pacientes de la Red de Salud UC. Métodos: Estudio retrospectivo de pacientes cuyos sueros fueron recibidos en el laboratorio de Microbiología para estudio serológico de brucelosis. Se obtuvieron 2 grupos, aquellos que cumplían criterios diagnósticos de brucelosis [cuadro clínico compatible, y/o hemocultivo positivo y/o serología por seroaglutinación en tubo (SAT) en títulos > 1/160] y el grupo control. Todos los sueros se analizaron mediante aglutinación con inmunocaptura (Brucellacapt®), ELISA IgM y ELISA IgG. Resultados: De 10 pacientes con brucelosis, los resultados serológicos fueron: 8/10 positivos para ELISA IgG, 7/10 para Brucellacapt® y SAT y 5/10 para ELISA IgM. Discusión: ELISA IgG por si solo fue la mejor prueba para el diagnóstico de brucelosis. La combinación ELISA IgG+ Brucellacapt® alcanza un buen rendimiento de detección (9/10) y puede ser una alternativa a la SAT.

Introduction: The diagnostic difficulties of brucellosis makes the evaluation of new diagnostic tests necessary. Objectives: Evaluation of different commercial tests in the serological diagnosis of brucellosis by ELISA and immunocapture antibodies in a clinical series of patients with brucellosis of the Health Network of the Catholic University of Chile. Methods: All the serums received in the Laboratory of Microbiology for suspicion of brucellosis during five years were studied. Two groups were obtained, one that fulfilled diagnostic criteria for brucellosis [clinical evidence, and/or positive blood culture and/or seroagglutination test (SAT) in titers > 1/160] and the control group. Each serum sample was analyzed using irnmunocapture-agglutination test (Brucellacapt®), ELISA IgM and IgG. Results: Of 10 patients with brucellosis, the serologic results were: 8/10 positives for ELISA IgG, 7/10 for Brucellacapt® and SAT, and 5/10 for ELISA IgM. Discussion: ELISA IgG alone was superior than SAT. The combination ELISA IgG/ Brucellacapt® reaches the best detection performance (9/10) and can be an alternative to SAT.