[Expand newborn screening using tandem mass spectrometry: two years' experience in Nuevo León, Mexico].
OBJECTIVE
To initiate a statewide expanded metabolic screening program in neonates with the purpose of identifying the most common inborn errors of metabolism.


METHODS
From March 2002 through February 2004, a blood sample was obtained between 24 and 48 hours after delivery from every consecutive child born in public hospitals in Nuevo León. It was spotted on filter paper and analyzed by tandem mass spectrometry for expanded metabolic screening.


RESULTS
A total of 42 264 samples were analyzed. Were obtained seven positive results, one for each disorder: homocystinuria, hyperphenylalaninemia, citrulinemia, transient tyrosinemia, 3-methylcrotonyl CoA carboxylase deficiency, 3-hydroxy-3-methylglutaryl CoA deficiency, and classic galactosemia.


CONCLUSIONS
The estimated incidence of inborn errors of metabolism is 1:5 000, with a false positive rate of 0.22%. The program permitted the identification of metabolic disorders in the newborn, allowing an early intervention and prevention of life-threatening events and permanent neurological damage.
Torres-Sepúlveda
María del Rosario
Mdel R
Departamento de Genética, Facultad de Medicina, Universidad Autónoma de Nuevo León, México.
Martínez-de Villarreal
Laura E
LE
Esmer
Carmen
C
González-Alanís
Rogerio
R
Ruiz-Herrera
Consuelo
C
Sánchez-Peña
Alejandra
A
Mendoza-Cruz
José Alberto
JA
Villarreal-Pérez
Jesús Z
JZ
D006801:Humans; D007231:Infant, Newborn; D008661:Metabolism, Inborn Errors / Q000175:diagnosis*; D008800:Mexico; D015997:Neonatal Screening / Q000379:methods; D053719:Tandem Mass Spectrometry; D013997:Time Factors