Abstract
La faringoamigdalitis es una infección muy frecuente en nuestro medio. Su etiología es múltiple, especialmente viral. El diagnóstico etiológico únicamente tiene interés en las faringoamigadalitis causadas por Streptococcus pyogenes o estreptococo betahemolítico del grupo A, puesto que se deben tratar con antibióticos para evitar las complicaciones, especialmente la fiebre reumática.
El diagnóstico se ha basado clásicamente en el aislamiento de la bacteria a partir del exudado faríngeo. No hay un método estandarizado para la realización de estos cultivos en cuanto al medio de aislamiento, la atmósfera de incubación o las pruebas mínimas de identificación que se deben realizar. Actualmente, en el mercado se dispone de múltiples reactivos que, por diferentes técnicas inmunológicas, permiten la detección del antígeno directamente en la muestra clínica. La mayoría de éstas presenta buenos valores de sensibilidad y de especificidad, aportando la ventaja de un resultado rápido, especialmente si se realiza en la misma consulta médica. Hay diferentes protocolos o estrategias para la atención de los pacientes con faringoamigadalitis. En cualquier caso, cada centro debe valorar el rendimiento de la técnica de detección de antígeno que se decida implementar, puesto que los resultados varían en función de las indicaciones y el cuidado en la obtención de la muestra.
Palabras clave: Faringoamigdalitis, Streptococcus pyogenes, Cultivo, Detección de antígenos, Métodos moleculares
Abstract
Tonsillitis and pharyngitis are highly frequent infections in Spain with multiple causes, especially viruses. Etiologic diagnosis of pharyngitis is only important in Streptococcus pyogenes or group A β-hemolytic streptococcal infections because antibiotic therapy is mandatory to prevent further complications, especially acute rheumatic fever.
Diagnosis has classically been based on bacterial isolation from throat swabs. There are no standardized methods for this culture in terms of culture medium, incubation atmosphere or the identification tests to be performed. Currently, a large number of commercial reagents are available, which, through different immunological techniques, allow direct antigen detection in the clinical sample. Most of these products show good sensitivity and specificity values, with the added advantage of providing a rapid result, especially if they are performed at points of care. Many guidelines for the management of patients with pharyngitis and tonsillitis are available. Nevertheless, as antigen detection results can vary in each center according to the indications and the care taken in sample extraction, the method chosen should be evaluated before implementation.
Key words: Tonsillitis, Pharyngitis, Streptococcus pyogenes, Cultures, Antigen detection, Molecular techniques
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