[Gastrointestinal obstruction in the mosaic trisomy X]. / Obstrucción gastrointestinal en la trisomía X en mosaico.

Trisomic X is a sex chromosomal abnormality that may be presented in mosaic. This is not extremely rare, the majority of cases go undiagnosed. The prevalence has been established to 1/1000 females. It is clinically characterized by tall stature, microcephaly, hypertelorism, congenital abnormalities, and motor and language delays. The association between the trisomic X and gastrointestinal malformations is extremely rare. We report a case of mosaic trisomic X with gastric obstruction expanding the clinical spectrum of this entity and emphasizing its unknown pathogenesis.

[Frequency of imperforate anus and associated risk factors in patients with Down syndrome]. / Frecuencia del ano imperforado y factores de riesgo asociados en pacientes con síndrome de Down.

OBJECTIVES: To establish the frequency of imperforate anus (IA) in the population with Down syndrome (DS) and study the associated risk factors. METHODS: An observational clinical study case control type was performed. The patients were evaluated at the Unit of Medical Genetics, University of the Andes, from February 2006 to February 2011. The patients with DS and IA were compared with 20 DS without IA. Antecedents of parents were obtained. RESULTS: The frequency de IA in the population with DS was 4.79%. The presence of fever in the first trimester of gestation and the rural origin were associated as risk factors of AI in patients with DS [OR: 25.33 (IC 95% 2.07- 310.76; P = 0.009) and OR: 7.50 (IC 95% 1.09 - 51.52; P = 0.043), respectively]. The maternal age superior to 35 years presented a marginal significance (P = 0.048). CONCLUSIONS: These papers emphasize the high frequency of IA in patients with DS and recommend to investigate the prenatal and environmental risk factors that can increase the presence of this anorectal anomaly in the population with DS, in order to consider them in the programs of prevention of congenital pathologies.

Alteraciones cardíacas en el Síndrome de Down. Unidad de Genética Médica, Universidad de Los Andes, Mérida- Venezuela

El síndrome de Down es una entidad clínica-genética que se asocia frecuentemente con cardiopatías congénitas entre 40-60% y corresponde un aspecto importante en su evolución. Objetivo: Describir los diferentes tipos de alteraciones cardiacas presentes en los pacientes con síndrome de Down, evaluados en la Unidad de Genética Médica de la Universidad de Los Andes y compararla con estudios similares. Pacientes y métodos: Se realizó un estudio observacional y descriptivo desde enero de 2009 a diciembre de 2012 en 100 pacientes con síndrome de Down con estudio citogenético y de ecocardiografía. Resultados: Las cardiopatías congénitas se presentaron en 63% de los pacientes. La comunicación interventricular fue la lesión simple aislada más frecuente con 14 casos y la alteración cardiaca compleja aislada más frecuente fue el canal auriculoventricular completo en cuatro casos. Conclusiones: Las malformaciones cardíacas congénitas se presentan en una frecuencia importante en la población con síndrome de Down, los diversos tipos varían en diferentes etnias y en períodos diferentes en el mismo país. Se debe enfatizar la realización del diagnóstico precoz para evitar las complicaciones que se pueden exhibir de forma más rápida y graves en los individuos con esta entidad genética.

Down syndrome is a clinical-genetic entity that is often associated with congenital heart disease between 40-60% and has an important aspect in its evolution. Objective: Describe the different types of cardiac alterations present in patients with Down syndrome, evaluated at the Medical Genetics Unit of the University of Los Andes and compared with similar studies. Patients and methods: A descriptive and observational study was conducted from January 2009 to December 2012 with 100 patients with Down syndrome with cytogenetics study and echocardiography. Results: Congenital heart disease occurred in 63% of patients. The ventricular septal defect was the most frequent isolated single lesion with 14 cases and the complex cardiac dysfunction was the most frequent isolated complete atrioventricular canal in four cases. Conclusions: Congenital heart defects are present in a significant frequency in the population with Down syndrome, various types vary in different ethnic groups and in di erent periods in the same country. It should be emphasized the realization of early diagnosis to prevent complications that can be displayed in a more rapid and severe in individuals with this genetic entity.