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Efecto de zona post-zona en pruebas de flujo lateral de antígenos de Histoplasma puede causar resultados débiles o
Lieke Ten Have1, Jochem B Buil1,2, Karin van Dijk3
1Department of Medical Microbiology, Radboud University Medical Center, Nijmegen, The Netherlands.
Medical mycology
|January 22, 2026
Resumen
Puede ocurrir un efecto de zona post-zona con el Ensayo de Flujo Lateral (LFA) de antígenos de Histoplasma, lo que podría causar falsos negativos. Se recomienda precaución al interpretar los resultados negativos de LFA para la histoplasmosis, especialmente con alta sospecha clínica.
Área de la Ciencia:
- Micología
- Inmunodiagnóstico
- Enfermedades Infecciosas
Sus antecedentes:
- La histoplasmosis es una infección fúngica significativa, particularmente en áreas endémicas.
- Las herramientas de diagnóstico precisas y rápidas son cruciales para un tratamiento oportuno.
- Los Ensayos de Flujo Lateral (LFA) ofrecen una opción de punto de atención para detectar antígenos de Histoplasma.
Objetivo del estudio:
- Investigar la ocurrencia y el impacto de un efecto de zona post-zona en el Ensayo de Flujo Lateral (LFA) de antígenos de Histoplasma.
- Determinar si la dilución de la muestra puede mitigar posibles resultados falsos negativos debido al efecto de zona post-zona.
Principales métodos:
- Repetición de pruebas de muestras de orina positivas para Histoplasma utilizando el LFA.
- Evaluación de muestras no diluidas y diluidas en serie.
- Análisis de los resultados del LFA para discrepancias y posibles falsos negativos.
Principales resultados:
- Se observó un efecto de zona post-zona en 6 de 12 muestras positivas para Histoplasma.
- Una muestra arrojó un resultado falso negativo en su forma no diluida debido al efecto de zona post-zona.
- La dilución de dos muestras resultó en señales de LFA más débiles, pero aún positivas.
Conclusiones:
- El LFA de antígenos de Histoplasma puede ser susceptible a resultados falsos negativos causados por el efecto de zona post-zona.
- Los médicos deben tener precaución al interpretar los resultados negativos del LFA, particularmente en casos de alta sospecha.
- Se justifica una mayor validación del rendimiento del LFA, incluida la evaluación del fenómeno de zona post-zona, para el diagnóstico de la histoplasmosis.
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