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Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Radiol. Feb 28, 2016; 8(2): 132-141
Published online Feb 28, 2016. doi: 10.4329/wjr.v8.i2.132
Multi-modality imaging review of congenital abnormalities of kidney and upper urinary tract
Subramaniyan Ramanathan, Devendra Kumar, Maneesh Khanna, Mahmoud Al Heidous, Adnan Sheikh, Vivek Virmani, Yegu Palaniappan
Subramaniyan Ramanathan, Devendra Kumar, Maneesh Khanna, Mahmoud Al Heidous, Department of Clinical Imaging, Al-Wakra Hospital, Hamad Medical Corporation, Doha, Qatar
Adnan Sheikh, Department of Medical Imaging, the Ottawa Hospital, Ottawa, K1Y 4E9, Canada
Vivek Virmani, Department of Radiology, Dr. Everett Chalmers Hospital, Fredericton, NB E3B 5N5, Canada
Yegu Palaniappan, Shree Meenakshi Multi Specialty Hospital, Pudukottai 622001, India
Author contributions: All authors equally contributed to this paper with conception and design of the study, literature review and analysis, drafting and critical revision and editing, and final approval of the final version.
Conflict-of-interest statement: No potential conflicts of interest.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Dr. Subramaniyan Ramanathan, MD, DNB, Consultant, Department of Clinical Imaging, Al-Wakra Hospital, Hamad Medical Corporation, PO Box 82228, Doha, Qatar. rm_subbu2000@yahoo.com
Telephone: +974-50117935 Fax: +974-40114509
Received: August 26, 2015
Peer-review started: August 30, 2015
First decision: September 28, 2015
Revised: October 21, 2015
Accepted: December 18, 2015
Article in press: December 20, 2015
Published online: February 28, 2016
Processing time: 184 Days and 12.7 Hours
Abstract

Congenital abnormalities of the kidney and urinary tract (CAKUT) include a wide range of abnormalities ranging from asymptomatic ectopic kidneys to life threatening renal agenesis (bilateral). Many of them are detected in the antenatal or immediate postnatal with a significant proportion identified in the adult population with varying degree of severity. CAKUT can be classified on embryological basis in to abnormalities in the renal parenchymal development, aberrant embryonic migration and abnormalities of the collecting system. Renal parenchymal abnormalities include multi cystic dysplastic kidneys, renal hypoplasia, number (agenesis or supernumerary), shape and cystic renal diseases. Aberrant embryonic migration encompasses abnormal location and fusion anomalies. Collecting system abnormalities include duplex kidneys and Pelvi ureteric junction obstruction. Ultrasonography (US) is typically the first imaging performed as it is easily available, non-invasive and radiation free used both antenatally and postnatally. Computed tomography (CT) and magnetic resonance imaging (MRI) are useful to confirm the ultrasound detected abnormality, detection of complex malformations, demonstration of collecting system and vascular anatomy and more importantly for early detection of complications like renal calculi, infection and malignancies. As CAKUT are one of the leading causes of end stage renal disease, it is important for the radiologists to be familiar with the varying imaging appearances of CAKUT on US, CT and MRI, thereby helping in prompt diagnosis and optimal management.

Keywords: Congenital abnormalities; Kidney; Urinary tract; Multi cystic dysplastic kidneys; Pelvi ureteric junction obstruction; Computed tomography urography; Congenital abnormalities of the kidney and urinary tract; End stage renal disease; Horse shoe kidneys

Core tip: Congenital abnormalities of the kidney and urinary tract (CAKUT) are one of the leading causes of end stage renal disease. They can be classified on embryological basis in to three major categories: (1) abnormalities in the renal parenchymal development; (2) aberrant embryonic migration; and (3) abnormalities of the collecting system. Ultrasonography, computed tomography and magnetic resonance imaging are the primary imaging modalities used in the detection of various CAKUT. Clinical features vary widely depending on the type, severity and laterality of renal anomaly. Timely diagnosis is crucial in selected anomalies to minimize renal damage, prevent or delay the onset of end stage renal disease (ESRD), and provide supportive care to avoid complications of ESRD.