Learning objectives
To understand the normal embryological development of the kidneys.
To understand the development of congenital renal ectopia and fusion resulting from failures in embryological development.
To be able to recognize and correctly diagnose renal fusion anomalies and ectopia on various imaging modalities.
To appreciate some of the pathological consequences of congenital renal and renal tract anomalies.
Background
Congenital renal parenchymal anomalies occur in approximately 1% of the population [1].
The importance of these anomalies is two-fold.
First,
these anomalies should not be mistaken for pathology themselves.
Second,
it is important to recognise that pathology,
such as infection or calculus formation,
can occur more frequently in these anomalies.
Embryological development of the kidney and collecting system represents the complex interplay between two embryological structures: the metanephros and ureteric bud.
Congenital renal anomalies are the result of abnormal development,
abnormal migration and/or abnormal fusion....
Imaging findings OR Procedure details
Horseshoe kidney
Horseshoe kidney is the most common of all renal fusion anomalies,
accounting for 90% of all such anomalies,
and occur in approximately 0.25% of the population,
with a predilection for males in the order of approximately 2:1 [2].
Embryology
During ascent towards the renal fossa,
the foetal kidneys cross the umbilical arteries.
Any aberration in position of the umbilical arteries may result in fusion of the bilateral nephrogenic blastemas.
When this fusion occurs at the lower poles of the kidneys,
a U-shaped single...
Conclusion
The array of congenital renal anomalies is vast and complex.
Fusion and ectopic abnormalities are the result of aberrant fusion or migration of the kidneys during foetal development.
Correct diagnosis relies on understanding the normal embryological development of the kidneys and recognition of anomalies when this normal development has been altered.
Most congenital renal and urinary tract abnormalities are asymptomatic and incidentally discovered,
however they often put the patient at higher risk of developing significant pathological complications whose consequences can be minimised by early diagnosis...
Personal information
Dr.
Mahomed Osman
BBiomed.Sc MBBS
Resident Medical Officer
Logan Hospital
Corner Armstrong & Loganlea Roads
Meadowbrook
Queensland 4131
Australia
Phone: +61 432 365 974
Dr.
Matt Skalski
Diagnostic Imaging Resident
Department of Radiology
Southern California University of Health Sciences
16200 E Amber Valley Drive
Whitter
CA 90604
United States of America
Phone: +1 715 570 8860
Dr.
Ian Bickle
MBBCh BAO (Hons) FRCR
Department of Radiology
RIPAS Hospital
Jalan Ripas
Bandar Seri Begawan
Brunei
Dr.
Henry Knipe
BMedSci MBBS (Hons)
Radiology Registrar
Department of Radiology...
References
1.Lorenz EC,
Vrtiska TJ,
Lieske JC et-al.
Prevalence of renal artery and kidney abnormalities by computed tomography among healthy adults.
Clin J Am Soc Nephrol.
2010;5 (3):431-8.
2.Türkvatan A,
Ölçer T,
Cumhur T.
Multidetector CT urography of renal fusion anomalies.
Diagn Interv Radiol.
2009 Jun;15:127-134.
3.Türkvatan A,
Demir D,
Ölçer T,
Cumhur T.
Cake kidney: MDCT urography for diagnosis.
Clinical Imaging.
2006;30:420-422.
4.Türkvatan A,
Ölçer T,
Cumhur T,
Akdur PÖ.
Multidetector computed tomographic urography for evaluation of crossed fused renal ectopia.
Journal of Ankara University...