HYDRONEPHROSIS IN CHILDREN: FROM PERINATAL DIAGNOSIS TO TREATMENT
DOI:
https://doi.org/10.46793/PP260102012TKeywords:
hydronephrosis, prenatal period, ureteropelvic junction, surgeryAbstract
Hydronephrosis is defined as dilation of the renal pelvicalyceal system and represents the most common prenatally detected urological anomaly. Although its incidence is approximately 1 in 100 pregnancies, clinically significant obstructive uropathy is considerably less frequent. The primary objective of evaluation is to identify obstructive dilation associated with increased intrapelvic pressure and risk of progressive renal damage. Ureteropelvic junction (UPJ) obstruction is the leading cause of pediatric hydronephrosis. Obstruction may result from intrinsic anatomical narrowing, disordered ureteral peristalsis (functional obstruction), or extrinsic compression, most commonly by aberrant renal vessels. Several anatomical variants exist, and UPJ obstruction may coexist with vesicoureteral reflux or other congenital anomalies. Ultrasound is the cornerstone of both prenatal and postnatal assessment, with grading based on anteroposterior pelvic diameter and SFU classification. Further diagnostic workup includes voiding cystourethrography, diuretic renography, and magnetic resonance urography in selected complex cases. The risk of renal impairment is estimated indirectly through the degree of dilation, split renal function, and drainage patterns. Management strategies include observation or surgical intervention. Pyeloplasty, most commonly the Anderson–Hynes technique, is indicated in patients with proven obstruction and declining renal function. In asymptomatic patients with preserved renal function, careful observation combined with antibiotic prophylaxis is often appropriate. Hydronephrosis requires an individualized and structured approach. Accurate interpretation of imaging findings and timely decision-making regarding intervention are essential to preserve renal function and achieve favorable long-term outcomes.
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