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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.
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Introduction: Histogenesis of kidney gives knowledge regarding histological maturity of kidney and its functionalstatus at the given gestational age. Kidney is developed from two parts, metanephrogenic blastema and uretericbud. Metanephrogenic blastema gives origin to secretory part i.e. nephron while ureteric bud forms the collectingpart i.e. collecting tubules and ureter. Both these parts fuse with each other and the development becomescomplete.Materials and Methods: 50 aborted human fetuses between 13-36 weeks of gestational age were used for thisstudy with no obvious congenital anomalies. The 2-3 mm thick cut sections of both kidneys were taken, processedand Paraffin blocks were prepared. 5-7 micron thick sections were taken with rotary microtome, mounted andthen stained with Haematoxylin and Eosin. Microscopic features were observed in low and high power and thendocumented.Results and Discussion: Differentiation between cortex and medulla was seen from 16-18 week onwards. Themedulla with collecting ducts, thick and thin segment of loop of Henle became well differentiated from 16 weekonwards. Vascularity of medulla increased with increase in gestational age while connective tissue decreasedwith increase in gestational age. Renal pelvis was lined by transitional epithelium.
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Introduction: The description of development of human kidney given in various textbooks doesn’t include detail microscopic appearance of kidney at various fetal ages. So an attempt was made in this study to gather information on this topic. Material and methods: The present study was carried out on 15 human fetuses of known gestational age (GA). The sections of kidney were processed and were stained using Hematoxylin and Eosin. Results: At 12th week of GA various stages of developing glomeruli were observed in the substance of the kidneys. In the cortex, various cut sections of the tubules were observed without any differentiation as proximal (PCT) and distal tubules (DCT). The second trimester section showed well differentiated the PCT and DCT by 16th week. Distinct brush border was observed in PCT by the 16th week. Immature duct system was observed in the medulla. The nephrogenic zone was appreciated till 36 weeks. By 28 th week the sections of DCT were observed adjacent to the renal corpuscles indicating the developing juxtaglomerular apparatus. Conclusion: As it is essential to know the developmental morphology of kidney, the present study explains every component of it in detail.