The Utility of Ureteral Jet Angle Sonography as Initial Screening Tool for Assessing Vesico-Ureteral Reflux in the Philippines: A Prospective, Cross-sectional Trial

Abstract

Introduction: One of the common risk factors in urinary tract infection is vesico-ureteral reflux. According to some studies, it is seen in 30%-50% of children and 40%-50% present with febrile urinary tract infection. The presence of moderate to severe reflux is an important risk factor in terms of acute pyelonephritis and reflux nephropathy. Investigation of children with urinary tract infection has undergone change so as to detect those who will benefit from diagnosis and treatment at the same time avoid over investigation.1

Objective: The present study aimed to determine the role of ureteral jet angle (UJA) in detecting vesicoureteral reflux (VUR) as compared to the gold standard of voiding cystourethrography (VCUG).

Methods: A total number of 152 kidneys from 76 patients (37 female and 39 males) ages from 2 months up to 11 years old were included in this study. These patients presented with recurrent urinary tract infection as confirmed via routine urinalysis and/or urine culture and sensitivity and assessed to have vesico-ureteral reflux disease as confirmed by voiding cystourethrogram (VCUG). They were included regardless of the grade of reflux (grade I-V). Patients with urinary tract infection but negative VCUG were also included. Excluded from the study were parents with no consent, patients with neurogenic bladder disorder as cause of recurrent urinary tract infection, patients who had postoperative correction of vesico-ureteral reflux prior to ureteral jet angle sonography, patients currently taking medication for urinary tract infection and patients currenlty symptomatic for recurrent urinary tract infection i.e. fever, chills, dysuria. All of the participants underwent kidney, urinary bladder ultrasound with ureteral jet angle sonography and all data were collected.

Results: Out of 152 kidneys, vesicoureteral reflux was seen in 91 of them (60%). Low grade reflux defined as grade I or grade II reflux was present in 32 kidneys (21%) and high grade reflux defined as grade III-V reflux was seen in 59 kidneys (39%). In both right and left kidneys, no significant difference was observed in bladder volume and expected bladder capacity (EBC) by VUR status. On the other hand, there was a significant difference observed in volume to reach reflux by VUR status of both right and left kidneys.No significant difference was observed in UJA volume, EBC, EBC% and UJA degrees by VUR status in the right kidneys. On the other hand, UJA volume, EBC and EBC % was significantly different by VUR status in the left kidneys.All AUCs were less than 0.7 even if EBC was considered. Therefore, UJA may have poor ability to classify patients correctly according to their VUR status.

Conclusion: Doppler flow ultrasound measurement of ureteral jet angle may be a simple and real non invasive test in children of any age but it only showed poor correlation compared to voiding cystourethrography in detecting vesicoureteral reflux. The ureteral jet angle sonography may not be a good initial diagnostic test in assessing vesicoureteral reflux due to its low sensitivity and specificity in detecting the said disease.