RESUMO
BACKGROUND: Genetic amniocentesis is performed in México 25 years ago but only few works have been published. OBJECTIVE: To analyze clinical and cytogenetic findings in consecutive patients submitted to genetic amniocentesis. MATERIAL AND METHOD: An analysis was made of the clinical features, amniocentesis results and pregnancy outcome in 1500 consecutive cases of genetic amniocentesis. RESULTS: Sixty-eight fetuses with chromosomopathy (4.5%) were detected and two, with an inborn error of metabolism. The most frequent abnormalities were trisomy 21 (32 cases), trisomy 18 (10 cases), trisomy 13(6 cases), 45,X (6 cases), 47,XXY (4 cases). Pregnancy outcome is known in 474 patients (32%). There were five fetal losses (1%). Of the 68 cases with chromosomopathy, the outcome is known in 45, of which, 29 (64%) decided to have an abortion while 16 (35%) continued the pregnancy, six had a spontaneous abortion or perinatal death and ten had an alive new born. Among fetuses with normal or balanced karyotype and normal ultrasound, 11 out of 419 (2.6%) had congenital anomalies. Two of them had a condition known to be related with epigenetic regulation, (Russell Silver and Angelman syndrome). CONCLUSIONS: Amniocentesis is a reliable and low risk method. Cytogenetic findings in this series are similar to those reported in the literature. Most patients with fetal disease decided to have an abortion. The finding of two patients with a condition related with abnormal epigenetic regulation suggests that the magnitude of this risk remains to be defined.
Assuntos
Amniocentese , Transtornos Cromossômicos/diagnóstico , Aborto Eugênico , Adulto , Amniocentese/efeitos adversos , Amniocentese/estatística & dados numéricos , Transtornos Cromossômicos/embriologia , Transtornos Cromossômicos/genética , Feminino , Morte Fetal/epidemiologia , Idade Gestacional , Humanos , Recém-Nascido , Cariotipagem , México , Pessoa de Meia-Idade , Mucopolissacaridose VII/diagnóstico , Mucopolissacaridose VII/embriologia , Mucopolissacaridose VII/genética , Doenças de Niemann-Pick/diagnóstico , Doenças de Niemann-Pick/embriologia , Doenças de Niemann-Pick/genética , Trabalho de Parto Prematuro , Gravidez , Resultado da Gravidez , Gravidez Múltipla , Estudos Retrospectivos , Risco , Ultrassonografia Pré-Natal , Adulto JovemRESUMO
As Mucopolissacaridoses (MPS) correspondem a um grupo de doenças genéticas raras caracterizadas peladeficiência/ausência de enzimas lisossomais responsáveis pela degradação de glicosaminoglicanos (GAG). Uma vez não degradados,os GAG se acumulam em diversos tecidos do organismo, causando uma série de complicações patológicas, que iniciam desde o período fetal até a fase infantil. Foi realizada a implantação de um protocolo laboratorial para o diagnóstico de pacientes com MPS, através da mensuração da atividade de duas enzimas lisossomais: beta-glicuronidase e arilsulfatase B, deficientes nas MPS VII e VI, respectivamente. Os valores encontrados em indivíduos normais corresponderam aos valores de referência descritos para a doença. Umpaciente com suspeita clínica de MPS demonstrou níveis normais de ambas as enzimas, o que exclui a possibilidade do mesmo possuir MPS VI ou VII. A implantação de protocolos laboratoriais de mensuração enzimática na investigação de MPS permite a realização de diagnósticos mais rápidos e, dessa forma, pode contribuir para as condutas clínicas mais apropriadas.
Assuntos
Humanos , Protocolos Clínicos , Glicosaminoglicanos , Mucopolissacaridose VI/diagnóstico , Mucopolissacaridose VII/diagnósticoRESUMO
We investigated the effect of age and sex on the serum activity of hexosaminidase (HEX) and -glucuronidase (BGLU) in 275 normal term infants aged 12 h to 12 months. Up to six weeks of life, HEX was significantly higher in boys (P<=0.023). During the age period of 1-26 weeks, BGLU was also higher in boys, but differences were significant only at 2-6 and 7-15 weeks (P<=0.016). The developmental pattern of HEX and BGLU was sex dependent. HEX activity increased in both sexes from 4-7 days of life, reaching a maximum of 1.4-fold the birth value at 2-6 weeks of age in boys (P<0.001) and a maximum of 1.6-fold at 7-15 weeks in girls (P<0.001). HEX activity gradually decreased thereafter, reaching significantly lower levels at 27-53 weeks than during the first three days of life in boys (P = 0.002) and the same level of this age interval in girls. BGLU increased in both sexes from 4-7 days of age, showing a maximum increase at 7-15 weeks (3.3-fold in boys and 2.9-fold in girls, both P<0.001). Then BGLU decreased in boys to a value similar to that observed at 4-7 days of age. In girls, BGLU remained elevated until the end of the first year of life. These results indicate a variation of HEX and BGLU activities during the first year of life and a sex influence on their developmental pattern. This observation should be considered in the diagnosis of GM2 gangliosidosis and mucopolysaccharidosis type VII.
Assuntos
Glucuronidase/sangue , beta-N-Acetil-Hexosaminidases/sangue , Fatores Etários , Análise de Variância , Biomarcadores/sangue , Feminino , Gangliosidoses GM2/diagnóstico , Gangliosidoses GM2/enzimologia , Glucuronidase/fisiologia , Humanos , Lactente , Recém-Nascido , Masculino , Mucopolissacaridose VII/diagnóstico , Mucopolissacaridose VII/enzimologia , Fatores Sexuais , beta-N-Acetil-Hexosaminidases/fisiologiaRESUMO
Recently we identified a P408S, P415L allele of beta-glucuronidase in several Mexican patients with mucopolysaccharidosis type VII (Sly syndrome) and presented evidence that both mutations are required to produce the MPS VII allele (Islam et al., 1996). In an attempt to determine whether either of these mutations exists as a benign polymorphism among Mexicans, we developed a PCR method to screen simultaneously for both mutations and used it to screen a population sample of 187 Mexican individuals in the Guadalajara area, all from the north-western states of Mexico. Neither mutation was present in 374 alleles studied. In addition, we had the opportunity to carry out prenatal diagnosis in a fetus at risk for homozygosity for this MPS VII allele at the 15th week of gestation using enzymatic assays as well as by analysis of genomic DNA isolated from cultured amniotic fluid cells. The fetus was found to be heterozygous for the P408S, P415L allele. The newborn's heterozygosity was confirmed after birth by enzyme assays on plasma and leukocytes, and by analysis of DNA from leukocytes.