International Classification of Vesicoureteral Reflux

Vesicoureteral reflux (VUR), the most common urinary tract pathology in children, is a term which denotes the backward flow of urine from the bladder to the ureters. It may be primary or secondary, depending on whether the condition occurs in the presence of a normal or dysfunctional urinary tract, respectively.

Signs and symptoms may vary based on the age of the child, but include failure to thrive, increased irritability, anorexia, lethargy, vomiting, diarrhea, fever, vague abdominal pain and symptoms of urinary tract infection (UTIs).

Management considerations include surveillance, medical therapy and surgery. Either of these approaches, or a combination of the three, may be opted for, but the condition must first be diagnosed using adequate diagnostic tests beforehand. Diagnosis involves the employment of laboratory tests, which include urine analysis to identify the microorganisms responsible for the UTI. This is further aided by imaging studies to detect underlying structural abnormalities, and urodynamic investigations to ascertain the functionality of the urinary system. Treatment varies depending on the severity of the VUR, which is graded into 5 distinct categories with the help of a voiding cystourethrogram (VCUG).

Voiding Cystourethrogram

VCUG is the standard diagnostic modality used for the grading of VUR, because it allows one to obtain a fine anatomical outline of the urinary system. It is a noninvasive procedure that employs the use of fluoroscopic X-rays together with contrast material to produce a picture of the bladder and the urinary tract. The fluoroscopic X-rays make it possible to see the bladder in motion in real time. The entire examination takes up to half an hour, may be performed at an outpatient clinic and is more or less painless. However, some children may understandably be scared of the process and need reassurance.

The bladder is catheterized and contrast is introduced through the same catheter. Once the bladder is full, the patient, while positioned on the X-ray platform, will urinate into a container conveniently placed nearby. Fluoroscopic screening is used to monitor bladder filling and emptying, which is by means of X-rays taken throughout this process. Particular attention is paid to whether or not there is retrograde flow of contrast material from the bladder to the ureters.

VUR Classification

VUR is graded on a scale of 1 – 5, with 5 being the most severe.

On VCUG, patients are classified as having grade 1 VUR if there are varying degrees of dilation of the ureters, but the reflux has not reached or does not affect the renal pelvis.
Patients with grade 2 VUR have reflux that affects the renal pelvis, but there is no dilation within the collecting system and the fornices are normal.

Grade 3 VUR presents with mild to moderate dilation of the collecting system with normal or minimally blunted fornices.
Grade 4 VUR exhibits moderate collecting system dilation and ureteric tortuosity with blunt fornices, but visible papillary impressions.
With grade 5 VUR, there is severe dilation of the collecting system together with the disappearance of papillary impressions and reflux into intraparenchymal tissue. Furthermore, there is great ureteric tortuosity.

References

http://aeurologia.com/pdfs/articulos/109-eng.pdf
https://www.radiologyinfo.org/en/info.cfm?pg=voidcysto
https://radiopaedia.org/articles/vesicoureteric-reflux-grading-1

International Classification of Vesicoureteral Reflux

Voiding Cystourethrogram

VUR Classification

References

Further Reading

Dr. Damien Jonas Wilson