From the Guidelines
The initial workup for a patient suspected of having Vesicoureteral Reflux (VUR) should include a thorough history, physical examination, urinalysis, urine culture, and renal ultrasound, followed by a voiding cystourethrogram (VCUG) in patients with specific ultrasound findings, such as bilateral high-grade hydronephrosis or abnormal bladders with a history of febrile UTIs. For history, clinicians should inquire about urinary tract infections (UTIs), voiding patterns, constipation, and family history of VUR or renal disease 1. Physical examination should assess for abdominal masses, genital abnormalities, and signs of neurological issues affecting bladder function. Laboratory tests should include urinalysis and urine culture to identify active infection. Renal ultrasound evaluates kidney size, scarring, hydronephrosis, and structural abnormalities.
The VCUG is the gold standard diagnostic test, performed by filling the bladder with contrast material through a catheter and taking images during voiding to visualize reflux of urine from the bladder into the ureters and kidneys. The severity of VUR is graded I through V based on the extent of reflux and dilation. In children with recurrent UTIs, a dimercaptosuccinic acid (DMSA) renal scan may be performed to assess for renal scarring, as it is considered the best nuclear agent for visualising cortical tissue and differential function between the two kidneys 1.
Key aspects of the workup include:
- Evaluating the overall health and development of the child, including height, weight, and blood pressure
- Assessing renal status through serum creatinine and GFR
- Evaluating bladder and bowel function, as bladder and bowel dysfunction (BBD) is common in toilet-trained children presenting with UTI with or without primary VUR and increases the risk of febrile UTI and focal uptake defects on a radionuclide scan 1
- Considering the presence of renal cortical abnormalities, bladder dysfunction, and breakthrough febrile UTIs as negative predictive factors for VUR resolution 1
This comprehensive approach is necessary because VUR predisposes patients to pyelonephritis and potential renal scarring, which can lead to hypertension and chronic kidney disease if left untreated. The management goal is preservation of renal function, and treatment approaches include watchful waiting, intermittent antibiotic prophylaxis, and surgical options like endoscopic injection of bulking agents or ureteral reimplantation 1.
From the Research
Initial Workup for Vesicoureteral Reflux (VUR)
The initial workup for a patient suspected of having Vesicoureteral Reflux (VUR) involves several diagnostic tests, including:
- Voiding cystourethrography (VCUG) 2, 3, 4
- Contrast-enhanced urosonography (ceVUS) 2
- Renal-bladder ultrasound (RBUS) 3, 4, 5
- Dimercaptosuccinic acid scan (DMSA) 3, 5
Diagnostic Test Characteristics
The characteristics of these diagnostic tests are as follows:
- VCUG: considered the gold standard for diagnosing VUR, but requires bladder catheterization and exposes children to radiation 3
- ceVUS: has high sensitivity and specificity, and is a low-risk examination method 2
- RBUS: has poor sensitivity and negative predictive value for detecting high-grade VUR, especially in patients under 2 years of age 5
- DMSA: has high sensitivity for detecting high-grade VUR, but low specificity, resulting in a large number of false positives 3
Patient Evaluation
The evaluation of patients suspected of having VUR should include:
- Urinalysis and urine culture to confirm the presence of a urinary tract infection (UTI) 4, 6
- Renal function tests to assess kidney function 4
- Imaging studies, such as VCUG, ceVUS, RBUS, or DMSA, to confirm the diagnosis of VUR and assess its severity 2, 3, 4, 5
High-Risk Patients
High-risk patients, such as those with recurrent UTIs or fetal or postnatal hydronephrosis, should be screened for VUR using a combination of diagnostic tests, including VCUG, ceVUS, and RBUS 4. The incidence of VUR is higher in patients with recurrent UTIs, especially in those under 1 year of age 4.