Resumen
La fenilcetonuria es un error innato del metabolismo con graves repercusiones neurológicas y sistémicas, si no se detecta antes del primer mes de vida. La implementación de pruebas de tamizaje metabólico en la etapa neonatal, constituye una herramienta económica, sencilla y no invasiva, que permite por lo menos sospechar si un niño nace con esta patología. El presente artículo muestra evidencia del daño neurológico de un niño con diagnóstico tardío de fenilcetonuria (PKU) en la Fundación Instituto de Habilitación “El Rosario” de Cartagena - Colombia, para niños con retardo mental. Este niño, tuvo un neurodesarrollo acorde a su edad hasta los siete meses, época en la que aparecieron crisis epilépticas, instalándose una encefalopatía epiléptica progresiva y con pobre respuesta a fármacos antiepilépticos. Se le practicó una tomografía axial computarizada (TAC), la cual no mostró daño estructural. Las crisis cesaron a los cuatro años, sin embargo, el paciente quedó con secuelas motoras y psíquicas. Sólo hasta los ocho años, después de una resonancia magnética nuclear (RM), se decidió practicar un tamizaje metabólico en suero y orina, cuyos resultados orientaron a solicitar pruebas más específicas, que permitieron cuantificar el aumento en plasma del aminoácido fenilalanina y confirmar el diagnóstico.
Es de resaltar que la realización de un tamizaje metabólico en la etapa neonatal o al momento de la aparición de los espasmos, hubiera permitido incidir favorablemente en el curso de esta enfermedad, evitando el daño neurológico por medio de la instauración de una dieta libre de fenilalanina en etapas tempranas del desarrollo
Citas
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