Vesicoureteric reflux
Updates to Article Attributes
Vesicoureteric reflux (VUR) is the term for abnormal flow of urine from the bladder into the upper urinary tract and is typically a problem encountered in young children.
For grading of vesicoureteric reflux, please refer to vesicoureteric reflux grading.
Epidemiology
The incidence of UTI is 8% in females and 2% in males 2. Out of all UTI affected children, incidence of VUR is at ~ 25-40%.
Clinical presentation
Reflux from the bladder into the upper urinary tract predisposes to pyelonephritis by allowing entry of bacteria to the usually sterile upper tract. As such the diagnosis is first suspected after a urinary tract infection in a young child.
Vesicoureteric reflux may be an isolated abnormality or associated with other congenital anomalies including:
Pathology
Vesicoureteric reflux is, in the majority of cases, the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunnel. As a result the normal pinch-cock action of the VUJ when bladder pressure increases during micturition is impaired, allowing urine to pass retrogradely up the ureter.
Radiographic features
The primary diagnostic procedure for evaluation of vesicoureteric reflux is a voiding cystourethrogram (VCUG), which however requires bladder catheterisation and distention of the bladder. This typically causes significant discomfort to the patient, requiring immobilisation of one form or another. In addition as it is a fluoroscopic examination it requires ionizingionising radiation, the dose of which varies greatly depending on the equipment and technique used.
As such other methods for assessing vesicoureteric reflux are being evaluated. These include:
- nuclear medicine studies
- ultrasound
- MR voiding cystography 3
Voiding cystourethrogram (VCUG)
Voiding cystourethrogram (also known as micturating cystourethrogram - MCU) should be performed after the first well-documented urinary tract infection up to the age of 6 years 3. VCUG should evaluate:
- presence and grade of VUR
- whether reflux occurs during micturition or during bladder filling
- presence of associated anatomical anomalies
Ultrasound
Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies.
Additionally ultrasound has been investigated as a replacement for traditional fluoroscopic voiding cystourethrogram, by assessing the distal ureters during bladder filling, using micro-bubbles 4.
Nuclear medicine
Reflux can also be graded, although less precisely, with nuclear cystography. There is no universally accepted grading system for nuclear cystography, with most radiologists simply using the terms mild, moderate, and severe 2.
Advantage of nuclear cystography is the lower radiation dosage, which makes it an excellent tool for screening female patients and for following up patients of both sexes.
Disadvantages of nuclear cystography are difficulty in recognizingrecognising important associated bladder disease (e.g. bladder diverticula), difficulty in visualizingvisualising the male urethra, and lack of spatial resolution.
MRI
MR voiding cystourethrogram protocols are still being developed but have the advantage of not having ionizingionising radiation and of simultaneously imaging the renal parenchyma 3.
Treatment and prognosis
If reflux is unrecognizedunrecognised and significant, not only are patients likely to develop recurrent urinary tract infections, but there infections can result in renal scars and eventually renal failure (reflux nephropathy).
Prompt prophylactic antibiotic treatment in low grades and surgical reimplantation in higher grades are aimed at reducing the risk of scarring and reflux nephropathy.
-</ul><h4>Pathology</h4><p>Vesicoureteric reflux is, in the majority of cases, the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunnel. As a result the normal pinch-cock action of the VUJ when bladder pressure increases during micturition is impaired, allowing urine to pass retrogradely up the ureter. </p><h4>Radiographic features</h4><p>The primary diagnostic procedure for evaluation of vesicoureteric reflux is a <a href="/articles/vcug">voiding cystourethrogram (VCUG)</a>, which however requires bladder catheterisation and distention of the bladder. This typically causes significant discomfort to the patient, requiring immobilisation of one form or another. In addition as it is a fluoroscopic examination it requires ionizing radiation, the dose of which varies greatly depending on the equipment and technique used. </p><p>As such other methods for assessing vesicoureteric reflux are being evaluated. These include:</p><ol>- +</ul><h4>Pathology</h4><p>Vesicoureteric reflux is, in the majority of cases, the result of a primary maturation abnormality of the vesicoureteral junction resulting in a short distal ureteric submucosal tunnel. As a result the normal pinch-cock action of the VUJ when bladder pressure increases during micturition is impaired, allowing urine to pass retrogradely up the ureter. </p><h4>Radiographic features</h4><p>The primary diagnostic procedure for evaluation of vesicoureteric reflux is a <a href="/articles/vcug">voiding cystourethrogram (VCUG)</a>, which however requires bladder catheterisation and distention of the bladder. This typically causes significant discomfort to the patient, requiring immobilisation of one form or another. In addition as it is a fluoroscopic examination it requires ionising radiation, the dose of which varies greatly depending on the equipment and technique used. </p><p>As such other methods for assessing vesicoureteric reflux are being evaluated. These include:</p><ol>
-</ul><h5>Ultrasound</h5><p>Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies. </p><p>Additionally ultrasound has been investigated as a replacement for traditional fluoroscopic voiding cystourethrogram, by assessing the distal ureters during bladder filling, using micro-bubbles <sup>4</sup>. </p><h5>Nuclear medicine</h5><p>Reflux can also be graded, although less precisely, with nuclear cystography. There is no universally accepted grading system for nuclear cystography, with most radiologists simply using the terms mild, moderate, and severe <sup>2</sup>.</p><p>Advantage of nuclear cystography is the lower radiation dosage, which makes it an excellent tool for screening female patients and for following up patients of both sexes.</p><p>Disadvantages of nuclear cystography are difficulty in recognizing important associated bladder disease (e.g. bladder diverticula), difficulty in visualizing the male urethra, and lack of spatial resolution.</p><h5>MRI</h5><p>MR voiding cystourethrogram protocols are still being developed but have the advantage of not having ionizing radiation and of simultaneously imaging the renal parenchyma <sup>3</sup>. </p><h4>Treatment and prognosis</h4><p>If reflux is unrecognized and significant, not only are patients likely to develop recurrent urinary tract infections, but there infections can result in renal scars and eventually renal failure (<a href="/articles/reflux-nephropathy">reflux nephropathy</a>). </p><p>Prompt prophylactic antibiotic treatment in low grades and surgical reimplantation in higher grades are aimed at reducing the risk of scarring and reflux nephropathy.</p>- +</ul><h5>Ultrasound</h5><p>Routine ultrasound is usually also performed (in addition to VCUG) to assess the renal parenchyma for evidence of scarring or anatomic anomalies. </p><p>Additionally ultrasound has been investigated as a replacement for traditional fluoroscopic voiding cystourethrogram, by assessing the distal ureters during bladder filling, using micro-bubbles <sup>4</sup>. </p><h5>Nuclear medicine</h5><p>Reflux can also be graded, although less precisely, with nuclear cystography. There is no universally accepted grading system for nuclear cystography, with most radiologists simply using the terms mild, moderate, and severe <sup>2</sup>.</p><p>Advantage of nuclear cystography is the lower radiation dosage, which makes it an excellent tool for screening female patients and for following up patients of both sexes.</p><p>Disadvantages of nuclear cystography are difficulty in recognising important associated bladder disease (e.g. bladder diverticula), difficulty in visualising the male urethra, and lack of spatial resolution.</p><h5>MRI</h5><p>MR voiding cystourethrogram protocols are still being developed but have the advantage of not having ionising radiation and of simultaneously imaging the renal parenchyma <sup>3</sup>. </p><h4>Treatment and prognosis</h4><p>If reflux is unrecognised and significant, not only are patients likely to develop recurrent urinary tract infections, but there infections can result in renal scars and eventually renal failure (<a href="/articles/reflux-nephropathy">reflux nephropathy</a>). </p><p>Prompt prophylactic antibiotic treatment in low grades and surgical reimplantation in higher grades are aimed at reducing the risk of scarring and reflux nephropathy.</p>
Image 10 Ultrasound ( update )
Unable to process the form. Check for errors and try again.