Changing trends in characteristics of infantile hydronephrosis.

Background: Hydronephrosis (HN) or calycial dilatation is the most common prenatal urologic abnormality. The aim of this study was to identify the possible changes in demographic and clinical manifestations of infantile HN in previously and recently diagnosed patients.

Methods: 193 children with infantile HN admitted to Ali-asghar Children's Hospital in two different periods (group 1; 1997-2003, and group 2; 2005-2011) were evaluated in this cross-sectional study. Variables such as time at diagnosis, gender, clinical manifestations, etiology, laterality, grade, and associated anomalies were also evaluated.

Results: The mean age at diagnosis was 32.3± 42.6 (group 1) and 21.4± 36.4 (group 2), respectively. 69.8% of patients were males. 75% of prenatally diagnosed patients were asymptomatic. Urinary tract infection was the most common symptom, followed by pain, hematuria, and decreased renal function. Obstruction in ureteropelvic junction was the most common etiology, accounting for 39.6% of all patients. Neurogenic bladder, vesicoureteral reflux, nephrolithiasis, and ureterovesical junction obstruction were the other common etiologies. 55.5% of all patients had unilateral HN, which was more common on the left side. No significant difference documented between two groups of patients, except for mild HN (23.7% vs. 39%), which was more common in newly diagnosed patients (p= 0.001).

Conclusion: There was no changing trend in demographic and clinical manifestations of infantile HN. However, the severity of infantile HN has been decreased significantly in recently diagnosed patients.