Is There a Correlation Between Anteroposterior Renal Pelvic Diameter (APD) and Vesicoureteral Reflux

Introduction: One of the most common reasons forkidney evaluation in neonates and infants is congenital hydronephrosis. The correct diagnosis (i.e. VUR or obstructive uropathy or transient hydronephrosis) and its treatment is of great value. This study was conducted to investigate the correlation between APD and VUR in congenital hydronephrosis.Material and method:All neonates with congenital hydronephrosis were investigated by ultrasonography. Neonates with hydronephrosis persisted after birth underwent voiding cystourethrography (VCUG). If VUR was detected, the next step was DMSA scan; otherwise DTPA scan was done to rule out obstructive uropathy. All cases were followed for at least 6 months to confirm the final diagnosis.Results: Out of 89 cases, 73 (82%) were male. There were 8 (8.98%), 36 (40.44%), 45(50.56%) cases of bilateral, right side and left side hydronephrosis, respectively. There were 20 (22.47%) cases of vesicoureteral reflux. Other diagnosis included ureteropelvic junction obstruction (UPJO), ureterovesical junction obstruction (uvjo) and transient hydronephrosis in 23(25.84%), 3(3.37%) and 43(48.31%) of cases, respectively.Mean APD was 17.85±11.71 totally, with minimum 4mm and maximum 60 mm. Mean APD in patients with VUR was 12.15±5.68 and 19.95±13.06 in cases without VUR. Mann-Whitney U test showed a significant correlation between APD and VUR, outcome (surgery or resolving) and APD with P value of 0.008 and 0.0001, respectively. In addition, Kruskal-Wallis test showed significant correlation between APD and final diagnosis (P value= 0.002).Conclusion: Postnatal APD in ultrasonography has significant correlation with the final diagnosis (including VUR, UPJO,UVJO and transient), outcome and VUR. APD could be valuable in the diagnosis of congenital hydronephrosis

Keywords:

congenital hydronephrosis , neonates , ultrasonography , vesicoureteral reflux