Determinación de ácido etilendiaminotetraacético por espectrometría de masas en tándem en muestras de sangre impregnadas en papel. Utilidad en la medida de tirotropina para cribado neonatal de hipotiroidismo congénito ?
- Daisy Castiñeiras
- José Ángel Cocho de Juan
- María Dolores Bóveda Fontán
- Luis Pérez Suárez
- Laura García Nimo
- Tegra Barreiro Martínez
- José María Fraga Bermúdez
ISSN: 1888-4008
Año de publicación: 2012
Volumen: 5
Número: 4
Páginas: 188-194
Tipo: Artículo
Otras publicaciones en: Revista del laboratorio clínico
Resumen
Introduction:Newborn screening programs use blood impregnated paper to analyze disease markers. The presence of EDTA in samples may interfere in the analytical methods used to measure these markers. For this reason, it is recommended not use anticoagulants in these samples. Moreover, it is not possible to recognize samples that have been collected into EDTA. Material and Methods: We developed and optimized an electrospray tandem mass spectrometry (ES-MS/MS) method to determine EDTA (ethylenediaminetetraacetic acid) in dried blood spots (DBS) on paper. We also included the method in the amino acids and acylcarnitines profile used for metabolic diseases neonatal screening. We also studied the EDTA influence on thyrotropin (TSH) neonatal screening analysis. Results: Optimized parameters for EDTA analysis in the blood eluate were found. TSH analysis was performed on DBS, serum and plasma samples from 110 patients. EDTA analysis on 2000 neonatal screening samples detected 0.74% of cases with EDTA contamination. Conclusions: The developed method is valid for the determination of this blood anticoagulant and can be included in the profile of amino acids and acylcarnitines by MS / MS to detect those samples that were taken improperly. The negative influence of EDTA in the determination of TSH by fluoroimmunoassay (AutoDELFIA®) has been confirmed. This could cause a false negative in neonatal screening for congenital hypothyroidism.