Hydronephrosis

Hydronephrosis is defined as dilation of the renal collecting system. this may result from obstruction or reflux of urine. In children,hydronephrosis is typically discovered during maternal-fetal ultrasound and accounts for approximately 0.5% to 0.6% of all uropathies seen in the neonatal period.

However, one in five neonates with the prenatal diagnosis of hydronephrosis will demonstrate spontaneous resolution of the hydronephrosis. In the neonates with hydronephrosis, ureteropelvic junction (UPJ) obstruction represents 44% of all postnatal causes of hydronephrosis

High-grade UPJ obstruction results in hydrostatic distention, increased intrapelvic pressure, and poor outflow of urine Chronic increases in intrapelvic pressure can result in damage to the kidney. However, with low-grade UPJ obstruction, the developing kidney can remain in a homeostatic state and often shows temporal growth and improvement.

The questions remain, “which patient requires surgical intervention,and which can be observed?”

The incidence of UPJ obstruction is 1 in 1250 births.It occurs more commonly in males. There is 66% for the left side in children. Both side cases of UPJ obstruction occur in 10% to 36% of patients, with the highest percentage occurring in the younger age group.

UPJ obstruction can affect infants, adolescents, or adults. The presentation of each differs. Typically, infants are asymptomatic and are now diagnosed by prenatal ultrasonography.

Obstructive causes of hydronephrosis include UPJ obstruction (44% incidence); UVJ obstruction (21% incidence); Multicystic dysplastic kidney, ureterocele, duplicated collecting systems (12% incidence); posterior urethral valves (9% incidence); ectopic ureter, urethral atresia, sacrococcygeal teratoma, hydrometrocolpos

Nonobstructive causes of hydronephrosis include VUR (14% incidence), physiologic dilation, prune-belly syndrome, renal cystic diseases, megacalicosis

Symptoms of UPJ Obstruction in Children flank pain abdominal pain vomiting infections Nephrolithiasis Hematuria Anorexia Asymptomatic

The management of possible UPJ obstruction watchful waiting and early intervention are two main options regarding the management of UPJ obstruction.

surgery The goal of surgery for UPJ obstruction is to preserve renal function by maintain unobstructed of the renal pelvis.

Anderson-Hynes pyeloplasty

Summary UPJ obstruction is the most common congenital urinary obstruction. radiographic studies reveal renal progressive hydronephrosis, and surgery is required.

Unfortunately, the factors that determine which kidneys require surgery have not been clearly defined at this point. However, with future developments in biochemical markers and improvements in radiographic studies, timing of surgical intervention will be defined earlier.

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