Nephrogenic Rests and Nephroblastomatosis Overview and Pathophysiology. Embryologic development of the kidneys is completed by the 36th gestational week. Residual embryonic fetal tissue (metanephric blastema) that persists beyond 36 weeks' gestation is called a nephrogenic rest . Multifocal or diffuse…
Renal Infection Acute Bacterial Pyelonephritis Overview. The term pyelonephritis encompasses infections of the renal parenchyma and pelvocaliceal system. Renal infections can be acute or chronic; unilateral or bilateral; and focal, multifocal, or diffuse. Potential complications include renal or perinephric abscess.…
Kidney and Ureter Multicystic Dysplastic Kidney Overview, Etiology, and Clinical Presentation. A multicystic dysplastic kidney (MCDK) is the most common form of cystic renal dysplasia. With high-grade obstruction or atresia of the upper urinary tract (renal pelvis and/or ureter) during…
Overview Fetal genitourinary system abnormalities encompass a wide spectrum of disorders varying in degrees of severity and include developmental anomalies, obstructive lesions in the urinary tract, and renal parenchymal diseases. The prenatal evaluation of the genitourinary system includes assessment of…
The urinary system and the genital system are closely associated embryologically and begin to develop during the fourth week of gestation. Both develop from the intermediate mesoderm along the posterior wall of the abdominal cavity. A longitudinal elevation of the…
Overview Trauma in children accounts for more than 500,000 hospital admissions and 20,000 deaths per year. After cranial trauma, the abdomen is the second most common site of injury, and approximately 80% of abdominal injuries are due to blunt force…
Tumors and tumor-like conditions affecting the colon in children can be divided into several categories. For the purpose of this chapter, we will discuss benign lymphoid hyperplasia, vascular lesions of the colon, and neoplasms. Several neoplasms arise in patients with…
Overview Intussusception is an acquired invagination of the bowel into itself ( Fig. 107.1 ). The more proximal bowel that invaginates into more distal bowel is termed the intussusceptum , whereas the recipient bowel that contains the intussusceptum is termed…
Colitis encompasses a spectrum of infectious and noninfectious inflammatory conditions. Infectious colitides, with etiologies often overlapping with enteritis (see Chapter 104 ), are typically acute in onset and may be localized as in acute appendicitis. The causative agent may not…
Overview Congenital and neonatal abnormalities of the colon can be divided into those that present in the neonatal period, such as colonic atresia and stenosis, imperforate anus, and functional colonic abnormalities, such as small left colon syndrome and meconium plug.…