Factores de riesgo de ocurrencia y gravedad de malformaciones congénitas / Identification of risk factors for congenital malformations

Background: The relative importance of congenital malformations as a cause of death in the first year of life is increasing along with the control of preventable causes of perinatal mortality. Aim: To identify risk factors for congenital malformations. Patients and Methods: Retrospective case-control study of births registered in the database of The Latin American Collaborative Study of Congenital Malformations (ECLAMC), in the period 2001-2010. Results: Birth weight and gestational age were significantly lower in cases than controls, behaving as risk factors and associated with a greater severity of congenital malformations. The risk and severity of congenital malformations increased along with mother’s age. Fetal growth retardation, a history of congenital malformations in the family, physical factors and acute illnesses of the mother in the first trimester of pregnancy were also significant risk factors for congenital malformations and their severity. The educational level of the mother was a protective factor for congenital malformations and their severity. Conclusions: Variables previously identified as risk factors for congenital malformations, were significantly related with the occurrence of congenital malformations and their severity.

Valor de la secuencia de difusión en el estudio de cáncer de próstata en pacientes con antígeno prostático específico elevado / Value of diffusion-weighted sequences in the study of prostate cancer in patients with increased prostate specific antigen levels

En el carcinoma prostático la arquitectura glandular es reemplazada por células cancerosas, produciendo barreras al movimiento del agua, que pueden ser estudiadas con resonancia magnética potenciada en difusión. Para evaluar el aporte de estas secuencias en el estudio de la próstata, realizamos estudio descriptivo e inferencia!, utilizando difusión en 26 pacientes con tacto rectal anormal y antígeno prostático elevado. Se analizó sensibilidad, especificidad y curvas ROC basadas en coeficiente aparente de difusión (CAD). Se realizó biopsia prostática en 14 pacientes; 7 resultaron positivos. Con CAD <1000 um2/s, se encontraron altas sensibilidades con bajas especificidades y valores predictivos moderados. Incorporando T2 mejoraron: certeza diagnóstica, especificidad y valores predictivos. Al comparar los valores CAD en zonas con y sin cáncer, obtuvimos diferencias para CAD promedio y mínimo. Las curvas ROC mostraron áreas elevadas y significativas, sugiriéndose valores de corte de 1059 um2/s y 969 um2/s entre "normales" y con cáncer; LR(+) para valores de corte: 6,97 y 5,23 respectivamente. Nuestros resultados permiten proponer que se obtiene mayor ganancia diagnóstica en la interpretación conjunta de imágenes T2 y secuencias de difusión y que CAD permite diferenciar entre tejido normal y cáncer, por lo que se debiera incorporar en el estudio prostático.

In prostatic carcinoma, the glandular architecture is replaced by cancer cells producing barriers to water motion, anomaly that can be studied through diffusion-enhanced MRI technique. To assess the contribution of these sequences in the prostate cancer exploration, we conducted a descriptive and inferential study using diffusion-enhanced MRI technique in 26 patients with abnormal digital rectal examination (DRE) and increased prostate specific antigen (PSA) values. We analyzed sensitivity, specificity and ROC curves based on apparent diffusion coefficient (ADC). Seven out of 14 biopsies were positive in patients undergoing prostate biopsy. When applying ADC <1000 _m2/se, high sensitivity with low specificity levels, as well as moderate predictive values were obtained. By incorporating T2-weighted images, improved diagnostic accuracy, specificity and predictive values were achieved. When comparing ADC values in tissues with and without cancer, average and minimum ADC appeared to exhibit different values. ROC curves depicted increased and significant values, suggesting cutoff values of 1059 um2/s and 969/um2/s for healthy and malignant tissues, respectively; LR (+) for cut-off value: 6.97 and 5.23, respectively. Our results enable us to propose that improved diagnostic outcomes are attained through combined interpretation of T2-weighted images and diffusion-weighted sequences and that the ADC permits discrimination between normal and malignant tissues. Therefore, we strongly support that these criteria should be taken into account when performing prostate explorations.