ABSTRACT
Los impactos más importantes de las expresiones tempranas del daño neurológico en los niños, son las dificultades para establecer intercambios con su medio social, afectando en la etapa inicial las primeras interacciones con su madre. Niños con riesgo biológico muestran grandes dificultades para iniciar interacciones. Cuando las madres se ajustan en una relación bidireccional se logra un aumento en las iniciaciones del niño; si las madres responden menos, los niños disminuyen las iniciaciones y aumentan la irritabilidad. Los programas de intervención temprana que integran en sus estrategias el manejo de las interacciones madre-niño se han considerado exitosos por sus implicaciones directas en el desarrollo del niño. Se requiere mayor soporte empírico sobre la influencia de patrones específicos de interacciones tempranas madre-hijo y el desarrollo posterior de niños con daño neurológico perinatal, en términos de prevención de alteraciones o discapacidad. Se realizó un estudio longitudinal y se reporta el efecto de las interacciones de reciprocidad madre-hijo en el desarrollo motor observado en niños a los 4, 8 y 12 meses de edad, a través del empleo del Modelo de Ecuaciones Estructurales (Curva de Crecimiento Latente). Se concluye que el modelo permitió mostrar que en niños de riesgo perinatal, las interacciones madre-hijo representan un buen predictor del desarrollo motor en el primer año de vida. Estos hallazgos tienen importantes implicaciones en la práctica clínica como estrategia integral para el diseño de acciones de intervención temprana debido a que los logros motores en los primeros meses representan un indicador predictivo del desarrollo infantil posterior.
The most important impact of early expressions of neurological damage in children is the difficulty of mixing up in their social environment which at the beginning affects their interactions with their mother. Children with biological risks show great difficulties to begin interactions. When mothers get adjusted to bidirectional relations with neurologically damaged children, an increase in the commencement of interactions by a child is achieved, while fewer responses of the mother to child produce fewer interactions and increases irritability. Early intervention programs which contain in their strategies management of mother-infant interactions have been considered effective for child development. However, further empirical studies are required, concerning the influence of specific patterns of early mother-infant interaction and future development of children with perinatal neurological damage, in terms of prevention of alterations or disability. The present longitudinal study reports the effect of reciprocity of mother-infant interactions in the motor development observed in children of 4, 8, and 12 months old, latent growth curve in structural equation modeling. This model permits the identifications of causal factors that could affect the results in different age groups and provides predictions of the relations in a more complex form than lineal relations. Based on the model designed, it could be shown that mother-infant interactions of reciprocity best characterized children with higher development level while the absence is seen in children with retarded development. We classified mothers and children in two types, respectively: interactive and organized mothers vs. non-interactive and disorganized ones; interactive and responsive children vs. non-interactive and non-responsive ones. Subjecting these two types of mothers and children to four possible combinations, the model results showed different motor development predictions in the children. On one hand, we estimated regression coefficient of four dyadic systems, obtained by combinations of different types of mothers and children: interactive and organized mother with interactive and responsive child (Dyadic system 1); interactive and organized mother with non-interactive and non-responsive child (Dyadic system 2); non-interactive and disorganized mother with interactive and responsive child (Dyadic system 3); and non-interactive and disorganized mother with non-interactive and non-responsive child (Dyadic system 4). Dyadic system 1 was associated with a better motor development in children with a mayor regression coefficient (19.82), followed by System 2 and System 3 (regression coefficient of 17.54 and 11.46, respectively). System 4 had a negative estimate value of regression coefficient (-11.27) in our model. On the other hand, we estimated intercept values according to the interactive type of these mothers and children. Among the four interactive types, solely two of them had statistically significant intercepts (p < .05), 
or = 66.13 for interactive children and or = 42.76, for non-interactive children. To predict the motor development of 4, 8, and 12 months old children, the slope with attenuation permitted to give a mayor model fitting, with the regression coefficient of 0, 1 and 1.5, respectively. This model presented excellent values of model fitting indicators (X² = .96, p = .97, CFI = 1.00, RMSEA = .00). This line of study should be widened, because motor development is the principal domain consolidated in the first months of life. It is fundamental in domain organizations of higher complexity as cognition and language. We conclude that this model showed that in high risk perinatal children, early mother-child interactions represent a good predictor of motor development in the first year of life. Moreover, we found that motor achievements in the first months of life can be a strong predictive indicator of future development of a child. These findings suggest the importance in clinical practice of observation and registration of mother-child interactions as part of an integral strategy of child evaluation.
ABSTRACT
OBJETIVO: Instituir un programa estatal de tamizaje neonatal ampliado para identificar errores innatos del metabolismo y determinar su prevalencia en la población de recién nacidos del estado de Nuevo León. MATERIAL Y MÉTODOS: Entre marzo de 2002 y febrero de 2004 se incluyeron neonatos consecutivos nacidos en hospitales públicos del estado. Se colectaron muestras de sangre en papel filtro entre las 24 y 48 horas de vida y se las sometió a tamiz metabólico mediante espectrometría de masas en tándem. RESULTADOS: Se analizaron 42 264 primeras muestras y se detectaron siete casos, uno de cada padecimiento: homocistinuria, fenilcetonuria, citrulinemia, tirosinemia/transitoria, deficiencia de 3-metilcrotonil-CoA carboxilasa, deficiencia de 3-hidroxi-3-metilglutaril-CoA liasa y galactosemia típica. CONCLUSIONES: La incidencia acumulada de defectos metabólicos en la población fue de 1:5 000 con 0.22 por ciento de casos falso-positivos. El programa permitió identificar y tratar con oportunidad los trastornos metabólicos al nacimiento con una efectiva prevención secundaria del retraso mental.
OBJECTIVE: To initiate a statewide expanded metabolic screening program in neonates with the purpose of identifying the most common inborn errors of metabolism. MATERIAL AND 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 percent. 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.