E2473. Congenital Anomalies and Pediatric Tumors of Kidneys and Urinary Tract
Ain Shams University/Faculty of Medicine
Detroit Medical Center/Wayne State University
Congenital renal anomalies are the most common cause of End Stage Renal Disease (ESRD) in pediatric patients, and cause significant morbidity in adulthood in the form of hypertension, urinary tract infections, and renal failure. Based on the understanding of the embryologic development of the kidneys, renal congenital anomalies can be differentiated into abnormalities in parenchymal development, abnormal migration, and anomalies of the collecting system. Ultrasound is usually the first modality used and can detect many abnormalities prenatally. Further evaluation by MRI, CT, or fluoroscopy can be done for confirmation of abnormalities and detection of complications. In addition, identification of renal malignancies, and differentiating them from mimicking benign anomalies is crucial for patient management.
Educational Goals / Teaching Points
Understand the embryologic basis of the congenital anomalies of the kidneys and the urinary tract; recognize the clinical presentation and diagnosis of the congenital anomalies of the urinary system; identify the radiologic features that distinguish each of the anomalies; understand the role of different imaging modalities in the diagnosis as well as management of congenital anomalies; and recognize the most common renal malignancies that present between the antenatal period and childhood, and their imaging features.
Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
Based on the understanding of the embryologic development of the kidneys, renal congenital anomalies can be differentiated into abnormalities in parenchymal development, abnormal migration, and anomalies of the collecting system. Aberrant parenchymal development leads to anomalies related to abnormal number (e.g. Renal agenesis, Supernumary kidneys), cystic kidney disease, and Renal hypoplasia. Abnormal migration can lead to abnormalities with location (e.g. ectopic kidney) or fusion of the kidneys (e.g. Horseshoe kidney). Finally, abnormalities with the collecting system development include Pelvi-Ureteric Junction Obstruction, and Duplex collecting system. Ultrasound is usually the first modality used and can detect many abnormalities prenatally. CT and MRI can be of additional value for confirmation and for detection of complications as well as other associated anomalies. Radiologists should thoroughly understand the imaging features of different congenital anomalies for early detection and treatment. In addition, renal malignancies of significant morbidity to the pediatric population include mesoblastic nephroma, multilocular cystic nephroma, and Wilms' tumor. Early detection of these malignancies and differentiation from other congenital anomalies is essential for optimal management.
As the most common cause of End-Stage Renal Disease (ESRD) in pediatric patients, and subsequently a cause of morbidity in adults, a thorough understanding of the congenital anomalies of the kidney is essential to prevent or delay the onset of ESRD. Differentiating renal malignancies from mimicking anomalies will help promptly direct clinical teams to the right diagnosis and management.