Diagnosis of the human fetal age based on the development of the normal kidney

Background and aims: The diagnosis of human fetal age is usually estimated based on the measurement of crown-rump length or crown-heel length and the weight of the fetus. However, this estimate is not totally accurate and sometimes is necessary to combine other data to determine the fetal age. An an...

ver descrição completa

Detalhes bibliográficos
Autores: Lizardo-Daudt,Helena Maria, Edelweiss,Maria Isabel Albano, Santos,Fernanda Teixeira dos, Schumacher,Rita de Cassia Alves
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2002
País:Brasil
Recursos:Sociedade Brasileira de Patologia (SBP)
Repositorio:Jornal Brasileiro de Patologia e Medicina Laboratorial (Online)
Idioma:inglés
OAI Identifier:oai:scielo:S1676-24442002000200010
Acesso em linha:http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1676-24442002000200010
Access Level:acceso abierto
Palavra-chave:Human fetal age
Fetal kidney
Staging of nephrogenesis
Descrição
Resumo:Background and aims: The diagnosis of human fetal age is usually estimated based on the measurement of crown-rump length or crown-heel length and the weight of the fetus. However, this estimate is not totally accurate and sometimes is necessary to combine other data to determine the fetal age. An analysis of the normal embryological development of the kidney may assist in this determination. The histology of this process, although well described, lacks photographic documentation. We intend to fill this gap by providing histologists and pathologists, especially inexperienced ones, with information about the staging of the renal development through microphotography. The objective of the present study was to achieve greater accuracy for the diagnosis of human fetal age through the proposed classification and the photographic documentation presented. Material and methods: Normal embryological development of the human kidney was studied by light microscopy. The fetal period from 6 to 40 weeks of gestation was observed according the stage of maturity of glomeruli and tubules; localization of glomeruli, occurrence of nephrogenic tissue and cortico-medullary differentiation. At least 5 different exams were observed from each week of development. Two hundred four exams were analyzed in the whole study. The histological characteristics were quantified and the process was documented by microphotography. Results and final considerations: The fetal development of the kidney was divided into 8 stages, which was documented through microphotography. Nephron structural formation occurred until the 34th week of prenatal development. From the 35th week on, tubules and glomeruli continued to mature without the formation of new nephrons. The proposed classification intends to improve the accuracy of the fetal age diagnosis.