Histogenesis of human fetal kidney from 14 weeks to 36 weeks: a study

Background: The knowledge of fetal human Kidney morphology and developmental anatomy is very important for prenatal diagnosis of disorders such as Wilm’s tumor, hydronephroses and congenital malformation etc.Methods: The study was carried out on 40 kidneys procured from 20 spontaneously aborted fetuses (11males and 9 females) ranging from 14wks-36wks of gestation, after confirming their age through  CRL they were grouped and then processed to form slides and stained with haemtoxylin and eosin and seen under light microscope.Results: All kidneys were lobulated at early gestational age and became fused by 36 wks. Corticomedullary junction and preformed collecting tubules were seen clearly by 18wks. Well differentiated PCT and DCT were formed by 19-23 wks. Well-formed pyramids by 28 wks and medullary rays by 29 weeks were clearly distinguished. Loop of Henle developed and distinguished by 28 wks. Increased vascularity was seen by 32-36 wks. Nephrogenic zone and undifferentiated mesenchyme decreased and matured glomeruli increased by 36 wks.Conclusions: The present study gave emphasis to the development of each component in medulla and cortex of kidney.

Caudal regression syndrome (sirenomelia) and its pathogenesis correlation: a case report.

Congenital anomaly characterized by an abnormal development of caudal region of the body with different degrees of fusion of lower extremities, bears resemblance of Sirenomelia or mermaid of Greek Mythology. This type of deformity is also known as Symmelia, Symposia, Sympus, Uromelia and Monopodia. It is associated with the single umbilical artery. It is associated with severe malformations of urogenital i.e. renal agenesis and absence of both internal and external genitalia. The aim of this study is to present, a rare congenital malformation Sirenomelia. In this context, we report a case of Sirenomelia illustrating the prenatal sonographic and pathological features. In our study 25 years old primigravida gave birth to still born full term baby, sex could not be identified. The specimen was collected from private nursing home at Ongole, no relevant history of consanguineous marriage or tobacco smoking or drugs taking etc. Fetal USG, X-ray & CT were taken after birth. Fetal autopsy was done; the gonad, thymus and umbilical cord were sent to histopathological examination. The etiopathogenesis and characteristic features of Sirenomelia were discussed with the findings and review of the literature.