Diagnóstico prenatal citogenético mediante amniocentesis durante los trimestres II y III de gestación en Costa Rica
Archivos
Fecha
2001-12
Tipo
artículo original
Autores
Castro Volio, Isabel
Sander Mangel, Kay
Vargas Prado, Manuel
Sánchez Chaves, Luis
Escalante López, Gerardo
Título de la revista
ISSN de la revista
Título del volumen
Editor
Revista de Biología Tropical 49 (3-4): 1227-1236, 2001
Resumen
El objetivo de este estudio fue identificar cromosomopatía fetal en voluntarias con embarazos de alto riesgo genético, brindar adecuada atención obstétrica y pediátrica y asesoramiento genético. En 842 embarazadas se obtuvo células fetales mediante amniocentesis, realizadas desde 1986 hasta 1999 inclusive. Las punciones se realizaron en hospitales del sistema de seguridad social y en la consulta privada. La indicación del 48 % de las amniocentesis fue el examen ultrasonográfico anormal y el 35 % de las pun- ciones fue por edad materna avanzada. El 66 % de las veces el estudio se realizó en el II trimestre del embarazo y el 34 % en el III trimestre. Se utilizó el sistema cerrado de histocultivo y la cosecha por suspensión. El resultado final se obtuvo en 14 días (mediana). De las 842 muestras de líquido amniótico, en 217 no fue posible obtener resultados. Los 625 cariotipos fetales fueron anormales en 55 casos (9 %): 33 cariotipos trisómicos (incluyendo una trisomía 13 por translocación Robertsoniana de los cromosomas 13 y 14), ocho casos con síndrome de Turner (45,X), tres mosaicos cromosómicos (incluyendo una trisomía 22 en mosaico) y 11 cariotipos anormales por otras causas. Al comparar la cantidad de defectos cromosómicos en relación a la indicación para efectuar la amniocentesis, se encontró un 17 % de cromosomopatía en los casos estudia- dos por ultrasonograma anormal y 2.5 % en los casos investigados por razón de la edad materna. En el seguimien- to de 211 casos se encontró concordancia entre el cariotipo y el fenotipo del recién nacido, al igual que entre el diagnóstico ultrasonográfico fetal y la condición del neonato. El diagnóstico prenatal de cromosomopatía permitió el asesoramiento genético y el manejo obstétrico y pediátrico de los casos de manera adecuada. En los embarazos con cariotipo normal, esta información alivió la preocupación de muchos de los padres.
The identification of fetal abnormal chromosomes in high risk pregnancies allows proper pediatric and obstetric management of the cases as well as genetic counseling. The results of 842 genetic amniocentesis from 1986 to 1999 are reported. All procedures were performed transabdominally and under ultrasound guidance, in hospitals of the social security system and in private facilities. There were two main reasons for referral: abnormal ultrasound assessment (48 % of cases) and advanced maternal age (35 %). Most procedures (66 %) were performed during the second trimester of pregnancy and 34 % during the third trimester. Fetal cells were closed cultured and suspension harvested. Median turn around time was 14 days. In 217 amniotic fluid samples no diagnosis could be obtained, mainly due to absence of cell growth in late gestation samples or because of blood contamination. Of 625 fetal karyotypes 55 (9 %) were abnormal, due to 33 trisomies (including a Robertsonian translocation trisomy 13), eight cases of monosomy X, three mosaics (including a mosaic trisomy 22), balanced and unbalanced translocations, extra structurally abnormal chromosomes and other defects. Pseudomosaicism was detected in five cases. Taking into account the reason for referral, cases studied as a result of abnormal ultrasound assessment exhibited 17 % abnormal karyotypes, in contrast to 2.5 % cytogenetic defects in pregnancies of women 35 years or older. Prenatal cytogenetic and sonographic findings correlated with the phenotype of the newborn in 211 cases available for follow-up. Prenatal diagnosis of fetal defects allowed genetic counseling as well as better obstetric management and pediatric care. Normal results of both tests provided reassurance to prospective parents.
The identification of fetal abnormal chromosomes in high risk pregnancies allows proper pediatric and obstetric management of the cases as well as genetic counseling. The results of 842 genetic amniocentesis from 1986 to 1999 are reported. All procedures were performed transabdominally and under ultrasound guidance, in hospitals of the social security system and in private facilities. There were two main reasons for referral: abnormal ultrasound assessment (48 % of cases) and advanced maternal age (35 %). Most procedures (66 %) were performed during the second trimester of pregnancy and 34 % during the third trimester. Fetal cells were closed cultured and suspension harvested. Median turn around time was 14 days. In 217 amniotic fluid samples no diagnosis could be obtained, mainly due to absence of cell growth in late gestation samples or because of blood contamination. Of 625 fetal karyotypes 55 (9 %) were abnormal, due to 33 trisomies (including a Robertsonian translocation trisomy 13), eight cases of monosomy X, three mosaics (including a mosaic trisomy 22), balanced and unbalanced translocations, extra structurally abnormal chromosomes and other defects. Pseudomosaicism was detected in five cases. Taking into account the reason for referral, cases studied as a result of abnormal ultrasound assessment exhibited 17 % abnormal karyotypes, in contrast to 2.5 % cytogenetic defects in pregnancies of women 35 years or older. Prenatal cytogenetic and sonographic findings correlated with the phenotype of the newborn in 211 cases available for follow-up. Prenatal diagnosis of fetal defects allowed genetic counseling as well as better obstetric management and pediatric care. Normal results of both tests provided reassurance to prospective parents.
Descripción
artículo -- Universidad de Costa Rica. Instituto de Investigaciones en Salud, 2001
Palabras clave
human cytogenetics, Genética humana, amniocentesis, prenatal diagnosis, fetal karyotypes, high risk pregnancy